11 September 2024
(10.00 am)
Lady Hallett: Mr Scott.
Mr Scott: Good morning, my Lady. May we please call Catherine Todd, who can be sworn.
Ms Catherine Todd
MS CATHERINE TODD (affirmed).
(Evidence via videolink)
Questions From Counsel to the Inquiry
Lady Hallett: Ms Todd, thank you so much for joining us this morning. I know how difficult this must be for you, it’s probably something you don’t want to relive, but it is so important that we do hear from you, so I’m really grateful to you.
The Witness: Thanks.
Mr Scott: Ms Todd, I would like to ask you some questions about the experiences of you and your partner TJ around the very sad death of your son Ziggy on 21 July 2021, a few hours after he was born.
It’s right that Ziggy was your first child?
Ms Catherine Todd: Yeah, he was.
Counsel Inquiry: And are you happy if I refer to him as Ziggy throughout?
Ms Catherine Todd: Yeah, that’s fine.
Counsel Inquiry: On 12 July 2021, you were approaching 28 weeks pregnant; is that right?
Ms Catherine Todd: Yeah, that’s correct.
Counsel Inquiry: You’d been due to attend a routine scan, but you’d tested positive for Covid, so you called the hospital’s maternity unit. What did they do as a result of that call?
Ms Catherine Todd: When I first phoned and reported to maternity that I was Covid positive, they had cancelled a scan that was upcoming.
Counsel Inquiry: Did they give you any guidance or advice about what to do or things to look out for as a pregnant lady with Covid?
Ms Catherine Todd: No, not at that time.
Counsel Inquiry: You started to feel very unwell but you also became aware that Ziggy wasn’t moving the way that he had been. What did you do as a result of that?
Ms Catherine Todd: I phoned maternity, both the EOU and the advice line multiple times. Their advice really at the time was just to take paracetamol and lie on my side for two hours, and drink a fizzy drink.
Counsel Inquiry: That seems fairly normal advice you’d get for a pregnant lady who is suffering from reduced foetal movement. Were you being told anything above and beyond that because you had Covid?
Ms Catherine Todd: No.
Counsel Inquiry: For how many days did you call?
Ms Catherine Todd: I think I first phoned maybe on the 12th – or the 13th, sorry, maybe, to say that I had Covid, and then up until Ziggy was born, so up until the 20th. I had an ambulance out as well to our house in between the phone calls.
Lady Hallett: Mr Scott, can you pause there, I’m not sure if anybody else is having some problems following the audio. Is it just me? Looks like it’s just me, nobody else is nodding, so I’ll look at the transcript.
Mr Scott: Well, you’re quite important, my Lady, so if there’s anything we can do to make it better –
Lady Hallett: As long as the stenographer can hear properly, that’s fine. So sorry to have interrupted, Ms Todd.
Mr Scott: What advice were you being given in those first few days, so the 12th, 13th, 14th, when you were calling the maternity unit?
Ms Catherine Todd: Every time it was really the same, just lie on my side and to phone back if I had any other concerns.
Counsel Inquiry: Did you ask for Ziggy to be checked?
Ms Catherine Todd: Yeah.
Counsel Inquiry: And what did they say?
Ms Catherine Todd: They told me that they wouldn’t bring me in at the time because they wanted to reduce the risk of spreading Covid.
Counsel Inquiry: How did that make you feel?
Ms Catherine Todd: Not reassured at all.
Counsel Inquiry: Do you think that you should have been examined sooner than you were?
Ms Catherine Todd: Yeah, definitely.
Counsel Inquiry: Do you think that you would have been seen earlier if you didn’t have Covid?
Ms Catherine Todd: Yeah.
Counsel Inquiry: It came to the point that you took yourself to hospital on 16 July; is that right?
Ms Catherine Todd: The – no, I had phoned them a few times on the 16th. Again they gave me the same advice: just lie on the side, drink a fizzy drink, take paracetamol. But a few hours later nothing had changed, so I phoned back again and said that I was coming up for the hospital to check Ziggy.
Counsel Inquiry: What made you take the decision to go up?
Ms Catherine Todd: I just felt at that time that it had gone on too long, and I was just getting the same advice and nothing was changing every time I was phoning.
Counsel Inquiry: When you went up, it’s right that you were 27 weeks and six days pregnant that day; is that right?
Ms Catherine Todd: Yeah.
Counsel Inquiry: When you went up – you have a partner TJ; that’s right?
Ms Catherine Todd: Yeah.
Counsel Inquiry: Did TJ go with you?
Ms Catherine Todd: He was not allowed into the hospital, he had to park outside, and they brought me through an ambulance bay just to be seen.
Counsel Inquiry: Were you told when at any point TJ may be allowed in while you were in there?
Ms Catherine Todd: I was told that he wasn’t allowed in at all.
Counsel Inquiry: When you were in, you didn’t receive a full – I’m going to call it a CTG scan, but you received a Doppler scan, so just a normal scan to listen to the baby’s heartbeat; is that right?
Ms Catherine Todd: Just a Doppler.
Counsel Inquiry: Was the midwife who carried out that scan wearing PPE?
Ms Catherine Todd: I think she was. It was the sister that had seen me, although after she had done the Doppler, she had told me to go back and wait in the car, that she needed to do a handover, she’d been there from half 7 that morning, and that I was fine and Ziggy was fine, and while I was waiting in the car for my notes to be brought out, she actually came out in her own clothes.
Counsel Inquiry: How long were you waiting in your car for?
Ms Catherine Todd: Maybe about five minutes after my Doppler was done.
Counsel Inquiry: How did you feel being asked to leave the maternity unity and go and wait in your car before you got your notes?
Ms Catherine Todd: Like I was just rushed in and out the door, no one really wanted to see me.
Counsel Inquiry: You provided a review of the circumstances of Ziggy’s death. One of the points that’s considered in that review is about the decision not to give you a CTG scan.
Ms Catherine Todd: Yeah.
Counsel Inquiry: And please do correct me if I’m wrong, but is it right that the guidance that was in place at the time for the hospital was that assessment of foetal heart rate by CTG was from 28 weeks onwards?
Ms Catherine Todd: That’s correct.
Counsel Inquiry: And because you were 27 weeks and six days, a CTG was not performed?
Ms Catherine Todd: Yep.
Counsel Inquiry: Were you asked to come back the next day, when you would have been at 28 weeks?
Ms Catherine Todd: No. I was just sent home and told that I was fine and that Ziggy was fine.
Counsel Inquiry: Were you told what to do if you still had concerns about Ziggy’s movements or lack of them?
Ms Catherine Todd: No.
Lady Hallett: Sorry to interrupt again.
Ms Todd, what was it about Ziggy that made you feel that you had had to go to hospital? What was it about the baby that made you think that something might be wrong?
Ms Catherine Todd: (Unclear) reduced and then I had also noticed my bump getting quite a lot smaller.
Lady Hallett: I don’t think the stenographer heard. What reduced? Was that the movement of the baby? Was it Ziggy’s movement?
Ms Catherine Todd: (Witness nods).
Lady Hallett: So Ziggy’s movement reduced and you thought your bump was smaller, so you thought he was smaller?
Ms Catherine Todd: Yeah, yeah.
Mr Scott: When you went in on 16 July, for how many days had you been concerned about reduced movements from Ziggy?
Ms Catherine Todd: Maybe from the 14th onwards.
Counsel Inquiry: Just if I can come back to the review about that in relation to the scan, it’s also noted that:
“The impact of maternal Covid-19 was not fully understood and led to this not being recognised as an independent risk factor when assessing reduced foetal movement; this resulted in [you] not having a CTG recording when [you] attended … on 16th July 2021.”
It continued:
“At the time the review, limited information was available about the effects of Covid-19 during pregnancy, particularly the strain of virus which was prevalent in Northern Ireland during the summer months of 2021.”
They:
“… were not obvious within the Obstetric teams in Northern Ireland until late August/early September 2021.”
How did you feel about that finding when you read it?
Ms Catherine Todd: Very let down. I don’t know why it took even past a year into the pandemic for them to have anything really in place for maternity.
Counsel Inquiry: In July 2021, had you heard there being concerns about risks associated with Covid during pregnancy?
Ms Catherine Todd: Not really, no.
Counsel Inquiry: What’s your thoughts about not being offered a CTG scan? How has that had a lasting impact upon you?
Ms Catherine Todd: I think that if they had have done the CTG they possibly would have picked things up and things could have been completely different.
Counsel Inquiry: Do you feel that you were able to ask or insist or press for a CTG scan?
Ms Catherine Todd: No. As I say, I felt like I was rushed in and out, no one really wanted me in the hospital for a start, obviously because I was Covid positive, so I think at the time they were just trying to get me out as quick as they could.
Counsel Inquiry: Do you think the situation might have been different if you had been allowed to have TJ or anyone else in with you?
Ms Catherine Todd: Yeah.
Counsel Inquiry: So, moving ahead about three days later, you were having difficulty breathing and you were having heart palpitations. How concerned at that point were you for both yourself and for Ziggy?
Ms Catherine Todd: Extremely concerned. I actually ended up phoning my GP the following day from having the ambulance out, because when the ambulance did come out they just checked me but not Ziggy, and I was kind of – at the time I was kind of up and down, one minute I was okay breathing-wise and then next minute breathing wasn’t great. I think maybe it had taken the ambulance about five hours or so to come out, but the following day my breathing had got worse and I just felt like the hospital, and when the ambulance came out they hadn’t really done much, so the following days, whenever I’d phoned my GP –
Counsel Inquiry: Can I just take those in steps. So what were you concerned about with Ziggy that led to, I think it was TJ who called the ambulance, wasn’t it?
Ms Catherine Todd: Yeah.
Counsel Inquiry: So what were your concerns about Ziggy that led to the ambulance being called?
Ms Catherine Todd: Well, I’d obviously noticed his movements reducing and then the sicker I was feeling, it was concerning me more that the two of us were really unwell at that point.
Counsel Inquiry: I think you said it was five hours?
Ms Catherine Todd: Yeah, I think it was around there.
Counsel Inquiry: That was for the ambulance to arrive from the time it was called?
Ms Catherine Todd: Mm-hm.
Counsel Inquiry: It arrived about 1.00 or 2.00 am; is that right?
Ms Catherine Todd: That’s right.
Counsel Inquiry: You said earlier on that when the ambulance arrived they didn’t check the baby. Do you remember anything about why the paramedics didn’t check on Ziggy?
Ms Catherine Todd: No, they didn’t tell me why. They just basically done my oxygen levels and blood pressure, and that was it.
Counsel Inquiry: Did you tell them about your concerns about Ziggy’s lack of movements?
Ms Catherine Todd: Yeah. I was more so phoning for him than me at that point.
Counsel Inquiry: Again, were you given any advice or guidance about what you should do?
Ms Catherine Todd: No, just the same thing again, take paracetamol and lie down.
Counsel Inquiry: So you were told to lie down, that was from the paramedics you were told to lie down when they’d just checked you?
Ms Catherine Todd: Yeah.
Counsel Inquiry: This was on 16 July, so you’d already been in this for a few days at this point, four or five days. What was your state of mind at that time when the paramedics left?
Ms Catherine Todd: I think being checked by both the sister in EOU and the ambulance, I was kind of thinking at the time maybe everything was okay, as that’s what they were telling me, and just to kind of – to trust them when I know now that I shouldn’t have, you know, I should have kind of pushed it further.
Counsel Inquiry: Did you feel looked after?
Ms Catherine Todd: No.
Counsel Inquiry: So you said earlier on that you called the GP about midday, so that’s about 11 hours or so after the ambulance had arrived. Could you tell us, please, what the GP said to you?
Ms Catherine Todd: She said to go straight to A&E and that she was going to fax over that I was coming so that they definitely had to see me.
Counsel Inquiry: Did she think that you might not be seen if she hadn’t informed them that you were coming?
Ms Catherine Todd: I think so. I think so. I think she also had faxed it over, so I kind of wouldn’t have been waiting as long, but I don’t think really it would have made a difference because obviously I was in A&E then waiting for maybe about ten hours.
Counsel Inquiry: You said you went to A&E and you just said you were waiting in A&E for ten hours; was that ten hours until you were seen or ten hours until you left, or …
Ms Catherine Todd: Ten hours in A&E in total, until I was moved over to maternity. I think at about five hours in, obstetrics came down and scanned me. They – I could see Ziggy and stuff moving then at the time –
Counsel Inquiry: Sorry, Ms Todd, I don’t want to jump ahead too quickly, I will definitely get there with you. I just want to talk about your waiting experience in A&E. You say that you were placed in what seemed to be a waiting area for people with Covid but it also seemed to be used for people with suspected Covid.
Ms Catherine Todd: Yeah.
Counsel Inquiry: What made you think that?
Ms Catherine Todd: There was a man who was shouting everywhere about how he wasn’t Covid positive. I think he was maybe like an asthmatic, probably, and they had just grouped his symptoms together basically and put him in the Covid area of A&E.
Counsel Inquiry: So it was July 2021, was there any kind of funnelling system or areas for people to wait depending on any kind of Covid status?
Ms Catherine Todd: They, at the A&E that I was in, they had – so the normal waiting room of A&E was people that they didn’t suspect to have Covid. Then they had a door that was like locked and security and beyond that door was just everyone that was either Covid positive or they had Covid symptoms.
Counsel Inquiry: Was that where you were because you’d had the positive test?
Ms Catherine Todd: Yeah.
Counsel Inquiry: Okay.
So you just said in A&E that they scanned Ziggy and that you could see him moving; were you given the results of that scan?
Ms Catherine Todd: No.
Counsel Inquiry: What were you told?
Ms Catherine Todd: That he was fine but their concern at the time was they’d arranged a liver function test that was done on me but they had no concerns really for Ziggy.
Counsel Inquiry: You talk about how you thought that the staff were all called into a meeting?
Ms Catherine Todd: Yeah.
Counsel Inquiry: Did you feel that everything was fine with Ziggy at that point?
Ms Catherine Todd: I did, yeah.
Counsel Inquiry: So were you taken from A&E round to the maternity ward?
Ms Catherine Todd: Yeah, a midwife, she came down with a wheelchair to take me round to maternity from A&E, but that was another five hours after he was scanned.
Counsel Inquiry: Was TJ with you at any point in this?
Ms Catherine Todd: No, he wasn’t allowed in.
Counsel Inquiry: Where was he, was he in the car park or somewhere else, or …
Ms Catherine Todd: At home. We only live maybe like five minutes from the hospital, so he stayed at home.
Counsel Inquiry: When you were scanned, round in the maternity ward, how many people were at that scan?
Ms Catherine Todd: Maybe about four or five.
Counsel Inquiry: What were you told were the results of that scan?
Ms Catherine Todd: That Ziggy had very little amniotic fluid around him and they were going to take me for an emergency section.
Counsel Inquiry: Did you have a chance to talk to TJ at that time?
Ms Catherine Todd: No, I just text him really quickly and then they had prepped me for the section.
Counsel Inquiry: Just before you go on, Ms Todd, because you talk about the alarms going off.
Ms Catherine Todd: Yeah.
Counsel Inquiry: How long were you left after the alarms went off?
Ms Catherine Todd: An hour.
Counsel Inquiry: Were you told what was happening?
Ms Catherine Todd: No. No one came in at all.
Counsel Inquiry: How did you feel about being left in that situation?
Ms Catherine Todd: Really unsafe.
Counsel Inquiry: Why do you think that there was a delay in carrying out that emergency C section?
Ms Catherine Todd: We had a meeting, maybe December time, with a few of the staff and they had told me the delay was because there was another baby that had, I think, an 80% survival rate, whereas at the time Ziggy only had 10, so they chose basically to go in with the other baby.
Counsel Inquiry: Do you think that there was enough staff there to be able to treat you and to give Ziggy an early C-section?
Ms Catherine Todd: No, not at all.
Counsel Inquiry: Did anybody contact TJ to tell him what was happening at this time?
Ms Catherine Todd: No, he actually contacted the hospital a few times himself. The first time I think he was told if I needed him that I would phone him, to which he replied “If she’s in having a section she’ll not have her phone”, and then he phoned another two times, I think, and they told him to stop ringing and that it wasn’t his information to know.
Counsel Inquiry: Did anybody else try and contact?
Ms Catherine Todd: Yeah, my mum and my elder sister, and they were told the same thing.
Counsel Inquiry: So did anybody know when you actually went in to have the C-section?
Ms Catherine Todd: No.
Counsel Inquiry: When was TJ allowed in?
Ms Catherine Todd: I had had the section and then brought back up to a room, so it wasn’t until later that night, a few hours maybe after Ziggy was born.
Counsel Inquiry: How did TJ feel in that time between when he found out that you were having a C-section and when he was actually allowed to see you?
Ms Catherine Todd: I think he was very anxious. He was at home with no information of what was going on. He was completely left in the dark.
Counsel Inquiry: What happened to Ziggy after you had had the C-section?
Ms Catherine Todd: I know when he was first born, he had a low Apgar score, so they had him basically in the corner with the team within NICU. They had done CPR and then taken him up to neonatal intensive care.
Counsel Inquiry: Did you have a chance to see him?
Ms Catherine Todd: No.
Counsel Inquiry: So when he was in the neonatal unit, did you have an opportunity or, put that a different way, did the nursing staff try and help you and TJ see Ziggy over that night?
Ms Catherine Todd: They tried to bring us round a few times during the night but they didn’t explain that they were bringing us round, they were just kind of putting me in full PPE and then into a wheelchair, and then the next minute I was back, they were getting me back out of the wheelchair and the PPE was off again.
Counsel Inquiry: Were you in a room or were you in the ward at that time?
Ms Catherine Todd: I was in a private – like a side room. I think it’s actually the bereavement room that’s in the hospital.
Counsel Inquiry: So you didn’t have to be in PPE in there?
Ms Catherine Todd: No.
Counsel Inquiry: Was TJ allowed to be in with you there?
Ms Catherine Todd: Yeah.
Counsel Inquiry: Was he allowed to be in there with you all night or did he have to leave?
Ms Catherine Todd: He – as soon as he came into the hospital, he stayed with me then in the room. We actually had a midwife who came in and sat – and this was after Ziggy had passed – sat on the floor and told him that he wasn’t allowed to leave. He basically said he hadn’t left, and she said, “That’s fine, you shouldn’t even be here, we’ve already bent over backwards for you, you shouldn’t even be here.”
Counsel Inquiry: How did it help you to have TJ with you that night before Ziggy passed away?
Ms Catherine Todd: I think it was more so the support because I hadn’t been given that option the whole time that, you know, Ziggy’s movements reducing, he wasn’t allowed into any scans and then again in A&E. So I think it was more so the support and he obviously was in the same boat that I was at the time, no one was telling us anything, so it was just the two of us kind of talking with each other.
Counsel Inquiry: Did you know how unwell Ziggy was that night?
Ms Catherine Todd: At the start they’d said that he was really unwell but then later on one of the midwives had made a comment that his obs had been picking up, that was just before we were brought round to meet him, so we actually thought he was getting better, a good bit better, before we were being brought round to see him the next day.
Counsel Inquiry: Do you think the fact that you were Covid positive had anything to do with the amount of information that you were being given about Ziggy’s condition overnight?
Ms Catherine Todd: Yeah, I think they were trying not to come in and out of the room as much as probably what they would have if I wasn’t Covid positive.
Counsel Inquiry: Were you or TJ receiving any food and drink, for example?
Ms Catherine Todd: Yeah.
Counsel Inquiry: You went round and saw Ziggy, was it about 8.30, 9.00 the following morning?
Ms Catherine Todd: Yeah.
Counsel Inquiry: What did you think Ziggy’s condition was before you saw him?
Ms Catherine Todd: As I say, the midwife had stated that his obs were starting to pick up, so we thought we were being brought round to meet him as he was getting better. We weren’t told at the time that he was palliative care or anything.
Counsel Inquiry: What did you find was – how was Ziggy when you went in?
Ms Catherine Todd: He was basically in an incubator, in a private NICU room that actually overlooked the main neonatal. There was a window so people could see in and we could see him there, but he had all the medical equipment on basically and when we came in they had taken him off everything and, again, we thought that he was getting a lot better at that point, that they were able to remove everything.
Counsel Inquiry: When did you find out that wasn’t the case?
Ms Catherine Todd: They took everything off and then handed Ziggy over to me, and then they just left the room, and then he passed away, and they didn’t come back for maybe about another two hours.
Counsel Inquiry: Was that the first time that you had been with Ziggy since he was born?
Ms Catherine Todd: Yeah.
Counsel Inquiry: Was that the only time that TJ got to see Ziggy?
Ms Catherine Todd: Yeah.
Counsel Inquiry: Were you having to wear full PPE when you were with him?
Ms Catherine Todd: Yeah, we had to show PPE. We had hairnets, masks, a visor, a full apron, gloves and I think shoe – like, shoe coverings.
Counsel Inquiry: What did you think about being asked to wear PPE to visit Ziggy?
Ms Catherine Todd: I thought it was unnecessary, especially at the time they knew how unwell he was, we didn’t. So now looking at it, I’m a bit confused as to why we were in full PPE, because, you know, if they knew that he was being taken off life support, I don’t understand who the PPE was protecting. Also he was in a private, like, infection room, so again, I don’t think it was necessary to have full PPE.
Counsel Inquiry: Wearing PPE, does that have a lasting impact upon your memories of your time with Ziggy?
Ms Catherine Todd: Yeah. All of our photos that we have with him are in full PPE.
Counsel Inquiry: How long were you with Ziggy for?
Ms Catherine Todd: We were – after he had passed, as I say, they left us in that room for about two hours, before they came back and then they brought us back to the bereavement room. I think – I’m not sure but I think they possibly had like washed him and stuff, we weren’t given the option again to do that, and then they brought him round to the bereavement room.
Counsel Inquiry: In those two hours did anyone come in and see you?
Ms Catherine Todd: No.
Counsel Inquiry: You said earlier on that in the room that Ziggy was in you could be seen from the outside?
Ms Catherine Todd: Yeah.
Counsel Inquiry: Was there a curtain or a screen or anything that was put up?
Ms Catherine Todd: Nothing. I think only after the SAI was done, because it was something that I highlighted, as there was another baby that was on the opposite side of the window and his – the baby’s dad – what I assume was the baby’s dad was able to watch everything.
Counsel Inquiry: You stayed in the hospital for some days afterwards. How much time was TJ able to spend with you?
Ms Catherine Todd: He stayed with me the whole time then in that room.
Counsel Inquiry: How beneficial was that for both of you, that you were able to spend time together?
Ms Catherine Todd: Really important. I think also it was really the only time that we got with Ziggy, so it was very important.
Counsel Inquiry: You had mentioned earlier on about the midwife coming over and saying, “You can’t be leaving this room, we’ve bent over backwards for you”. Was that two days after Ziggy had passed away?
Ms Catherine Todd: Yeah, he was actually on my chest at the time.
Counsel Inquiry: What was your overall view of the compassion that you, TJ and Ziggy received from the staff at that time?
Ms Catherine Todd: I don’t think – I don’t think there was any, at all. I don’t think anyone cared. I think they were too busy. They were rushing in and out of the room and just didn’t really care.
Counsel Inquiry: Do you think they knew what to do, how to cope with Covid and pregnant people at that time?
Ms Catherine Todd: Not at all.
Counsel Inquiry: Do you think there was enough staff to be able to look after everyone in the maternity unit at that time?
Ms Catherine Todd: No.
Counsel Inquiry: Were you offered any help with bereavement or grief while you were in hospital?
Ms Catherine Todd: I later learned that leaving the hospital we were supposed to have a bereavement midwife, as we were leaving, which we didn’t hear from until I think it was two weeks later, and she actually contacted TJ to tell him funeral arrangements that we had made.
Counsel Inquiry: You were told that Ziggy was to be sent for a postmortem?
Ms Catherine Todd: Yeah.
Counsel Inquiry: Do you know that – well, his body was going to have to be collected to be taken to a hospital in Liverpool for a postmortem; is that right?
Ms Catherine Todd: Yeah, that’s right.
Counsel Inquiry: Do you know the reason for that?
Ms Catherine Todd: No. No.
Counsel Inquiry: Had anyone ever told you whether there was anyone actually in Northern Ireland capable of carrying out a postmortem on a child at that time?
Ms Catherine Todd: No, that was really our only option, was that he went to Alder Hey and in the bereavement room they brought round like a DVD to watch of stages, basically, and what would happen, from timeframes to like who would be with him and – but obviously that didn’t happen either.
Counsel Inquiry: How important was it to you to know where Ziggy was at all times in that trip to and from Liverpool?
Ms Catherine Todd: Extremely important.
Counsel Inquiry: Were you kept informed about where he was?
Ms Catherine Todd: No, not at all. We were told that he would be picked up from the Ulster on the Monday and back on the Wednesday. When in turn it came to the Monday, I had heard nothing at all, so I contacted the hospital themselves, and they basically said they didn’t know where he was, he wasn’t there. They suggested that I contact the Royal mortuary, so when I done that they weren’t sure where he was either, and they told me to maybe phone Liverpool.
So I’d phoned Liverpool maybe that night and, again, I got a guy on the phone who wasn’t too sure. He said he didn’t think there was any babies that had come over from Belfast. Until the next morning, a lady from the Snowflakes team had contacted me to let me know that he wasn’t there and she didn’t – she had stayed in contact with me but then she phoned me again on the Wednesday morning. But on Tuesday night she had told me that there was two babies coming from Belfast but they didn’t know their names until they got there. So she phoned me maybe at about 6.00 Wednesday morning to let me know that he had arrived in Liverpool. So he had basically been in the Ulster the entire time.
Counsel Inquiry: So is it right that it was about two days where you didn’t know where Ziggy was?
Ms Catherine Todd: Yeah.
Counsel Inquiry: What did you think of the level of contacts that you had had from the hospital in Northern Ireland?
Ms Catherine Todd: I thought it was appalling.
Counsel Inquiry: Were you able to have an open coffin for Ziggy?
Ms Catherine Todd: In the end but very nearly no. The Ulster had put on “maternal Covid” on his death certificate and, as a result, the funeral directors’ policy was that they wouldn’t then be able to manage his body, and it was only from the lady actually that was working in the Snowflakes team over in Liverpool, she had phoned me just to see if we had a CuddleCot and, at the time, I didn’t even know what that was.
Counsel Inquiry: Could you just explain quickly what a CuddleCot is?
Ms Catherine Todd: It’s like a small Moses basket type shape, a device that keeps the baby cold, so you can spend more time with them.
Counsel Inquiry: How important was it to you at that time to spend time with Ziggy?
Ms Catherine Todd: Extremely important, especially –
Counsel Inquiry: How long – sorry.
Ms Catherine Todd: Sorry, just because we’d even been told that it was going to be a closed coffin, you know, it was really important to us that we got to make memories that were good.
Counsel Inquiry: How long did it take for you to be given a CuddleCot?
Ms Catherine Todd: When he came home, he was due to be home with the funeral directors, and because the lady from Snowflakes team had phoned, everything kind of had to be delayed, so we could arrange with the hospital to collect the CuddleCot. And I think, if I remember correctly, I think TJ actually had to go up and collect it himself.
Counsel Inquiry: You were talking about an open coffin. Is it right that it was only when the funeral home were told that Ziggy had had a negative PCR test that you were able to have an open coffin?
Ms Catherine Todd: Yeah. So the lady from Snowflakes team is the one who organised it all. She phoned round the Ulster from Liverpool to ask if he had a PCR. Now, we were never asked or gave consent for him to have a PCR done, but basically that’s – that’s the only reason why, is she then obtained it from the Ulster. And then she contacted the funeral directors as well, to let them know that Ziggy’s PCR was done by the hospital and it was negative.
Counsel Inquiry: This was a Snowflakes team, this is in Liverpool, it’s not a Northern Ireland service; is that right?
Ms Catherine Todd: Yeah.
Counsel Inquiry: How did you feel about the level of communication that you’d received about the CuddleCot, about the PCR that would allow you to have an open coffin?
Ms Catherine Todd: There wasn’t any. There wasn’t any communication. You know, it was – everything was done either by us or from another service that’s not in Northern Ireland.
Counsel Inquiry: Is it right that after Ziggy’s death and after the funeral arrangements you’d tried to get access to the records that were held about you and about Ziggy? How easy was it to get access to those records?
Ms Catherine Todd: Extremely difficult. We phoned and phoned, and a lady actually told TJ she wasn’t so sure why – why I wanted them, even to begin with, and he said – he had replied to her, saying “It doesn’t matter why she wants them, but if it helps her sleep then, you know, what’s the issue that she’s given them?” And basically then we were given half, we weren’t given the full – the full medical notes, we were only given half of them, and I think it was a few days even for them to photocopy that out. We’d never actually received our own – the green file, it’s just been a photocopy.
Counsel Inquiry: Do you think it was a battle to get those notes?
Ms Catherine Todd: Yeah.
Counsel Inquiry: I just want to ask about your overall impressions, Ms Todd. When you look back on all of your experiences in that period in July 2021, do you think that there were enough staff to treat you at that time?
Ms Catherine Todd: No.
Counsel Inquiry: Do you think that the staff knew how to treat a pregnant woman with Covid back in 2021?
Ms Catherine Todd: No.
Counsel Inquiry: Did you feel safe as a pregnant lady in Northern Ireland?
Ms Catherine Todd: Not at all, no.
Counsel Inquiry: It’s right that you’re pregnant now, is it?
Ms Catherine Todd: Yeah.
Counsel Inquiry: Do you feel safe as a pregnant lady in Northern Ireland now?
Ms Catherine Todd: No.
Counsel Inquiry: Did you feel listened to by medical staff in 2021?
Ms Catherine Todd: No.
Counsel Inquiry: You have since given birth, as you say. Is it right that some of those who had been involved in your time with Ziggy arrived at your bedside at the time when your child was born?
Ms Catherine Todd: Yeah.
Counsel Inquiry: How did that impact upon your experience with her?
Ms Catherine Todd: I don’t think it was necessary at all. I also was admitted the majority of my pregnancy with my second, and had people that were dealing with the SAI with Ziggy at the time come round to see me while I was admitted with my second, which again I don’t think there was any need for.
Counsel Inquiry: How have your experiences made you feel towards the healthcare system in Northern Ireland?
Ms Catherine Todd: I don’t have much hope in it.
Counsel Inquiry: Just finally, how are you now?
Ms Catherine Todd: Not – not great. It’s obviously something that’s completely impacted the rest of our lives, and I think we have just been left to deal with it ourselves. We’re kind of away from the hospital now and that’s all, you know, that matters to them, we’re out the door, and we’re the ones left with this for the rest of our lives, basically.
Mr Scott: Thank you, Ms Todd.
My Lady, I’ve no further questions.
Lady Hallett: Thank you very much indeed, Ms Todd, I hope we have not added to your trauma and grief. No one can ever replace Ziggy and I know that you and his father will never forget him and you will always miss him. I just hope that the new baby and your daughter can help you come to terms with the grief that I’m afraid is going to be with you forever. But thank you so much and best of luck with the new baby.
The Witness: Thank you.
Lady Hallett: Right. I think we’ll take a break now, Ms Todd, I think there are some people who may wish to speak with you, so Ms Campbell and others may just come and say – repeat the thanks, I suspect, that I have already given. And we will take a short break and then we will come back to the next witness. Thank you again.
(The witness withdrew)
(10.45 am)
(A short break)
(10.56 am)
Lady Hallett: Ms Carey.
Ms Carey: My Lady, before we call the next witness, can I deal with one matter. You have just heard, now, from four witnesses who are giving evidence from the bereaved groups across the UK, and in addition to publishing their statements the Inquiry also obtained statements from four other individuals: Seema Bhalla, Sam Smith-Higgins, Margaret Waterton and Fidelma Mallon. Can I invite you, please, to publish both the four people that we have heard from and indeed those four additional statements onto the Inquiry website.
Lady Hallett: Certainly. I should say I was re-reading the statements of the four bereaved that you are about to publish earlier today and they are all as moving as the evidence we have heard over the last few hours.
Also I should say that you mentioned I think in your opening about documents being published. The default setting will be publication unless there is a reason not to.
Ms Carey: Thank you very much, we are very grateful.
Can I invite now, please, Professor Clive Beggs to be sworn.
Professor Clive Beggs
PROFESSOR CLIVE BEGGS (affirmed).
Questions From Lead Counsel to the Inquiry for Module 3
Ms Carey: Thank you, sit down.
Professor, your full name, please?
Professor Clive Beggs: My name is Clive Barron Beggs.
Lead 3: You have provided, I think, a 132-page report to Module 3 dealing with the physical science underpinning Covid transmission, and its implication for infection prevention and control in healthcare settings?
Professor Clive Beggs: Yes, that’s the case.
Lead 3: It has the formal INQ ending 474276 and we will be going through a number of pages and paragraphs in it. I hope you have a copy in front of you.
Professor Clive Beggs: I have, yes.
Lead 3: Before we delve into the science, can I start with you, please, and a little bit about your background. It’s set out at pages 4 and 5 of your report, but does it come to this: that you are a bioengineer and a physiologist and an emeritus professor of applied physiology at Leeds Beckett University?
Professor Clive Beggs: I am, yes.
Lead 3: I think you are a multidisciplinary scientist, with more than 25 years researching the transmission of infection in hospitals, and you have worked in neurology as well?
Professor Clive Beggs: Yes, I have, yes.
Lead 3: You specialise in what is termed interdisciplinary research and you have particular expertise in the transmission of infectious diseases in hospitals?
Professor Clive Beggs: Yes.
Lead 3: And you also have particular expertise in ventilation and the behaviour of aerosols in the air, biophysics and the application of engineering interventions to mitigate the transmission of infection?
Professor Clive Beggs: Yes, those are all areas of my expertise.
Lead 3: Before entering academia, is it right that you worked as a professional engineer designing ventilation and air conditioning systems for buildings, and as such you have knowledge, indeed intimate knowledge, of hospital ventilation systems?
Professor Clive Beggs: Yes, that was the first part of my career.
Lead 3: I think during the Covid pandemic, you worked and served on the Royal Society Rapid Assistance in Modelling the Pandemic working group?
Professor Clive Beggs: I did, yes.
Lead 3: If it’s not clear from what I’ve just said, you are a research scientist but not a clinician?
Professor Clive Beggs: That is absolutely the case.
Lead 3: I think though that you know that the Inquiry has instructed a trio of experts with clinical background who can help in relation to that matter?
Professor Clive Beggs: Yes.
Lead 3: All right.
Can we take down, please, the screen, thank you very much.
Can we at the outset, please, try to ensure that when giving your evidence and – people reading your report understand the language and understand the science about the way that the Covid is transmitted. All right?
Professor Clive Beggs: Yes.
Lead 3: We’re going to look, firstly, at the language, and I think, Professor, you may have heard me explain that although obviously we’re dealing with SARS-CoV-2, for ease I’m going to try to just refer to it as Covid-19?
Professor Clive Beggs: Yes, and I will try to use the same but I probably will slip into SARS-CoV-2, please forgive me, but – and I’ll probably say SARS or SARS-CoV-1 for the other one –
Lead 3: For the other – all right. If there is any confusion we will do our best to clarify.
Professor Clive Beggs: But I will also talk about the spread of Covid as well.
Lead 3: Thank you.
Lady Hallett: When we’re talking about confusion, Professor Beggs, I was having a conversation with a doctor at the weekend, and of course “ventilation” gets used in two different ways in this context, doesn’t it?
Professor Clive Beggs: Yes.
Lady Hallett: There’s the ventilation which is opening the windows and you’ve got ventilating a patient.
Professor Clive Beggs: Oh, right, yes, absolutely. In fact I’ve had this happen in my professional life when we have been talking to clinicians and there’s been crossed wires.
Yes, you ventilate patients who are having problems with breathing in intensive care units and places like that, but in this occasion we’re not talking about that. I have done work on bits and pieces on that but in this case we’re talking about the ventilation of room spaces like this room here and air movement in rooms.
Lady Hallett: Thank you.
Ms Carey: Thank you.
All right, some basic terminology, please, and I think it starts on page 7 of –
Professor Clive Beggs: Yeah.
Lead 3: – your report but I just want to ask you about the language that you have used in the report because, as I think you are aware, there is not necessarily consensus about the terminology and we’re going to just be clear about what you mean by things and then we’ll look perhaps at what some other people say about the terminology. All right?
Professor Clive Beggs: Yes.
Lead 3: Can you help us, as a general starting point though, why does the terminology matter?
Professor Clive Beggs: Well, the reason it matters is because, historically, there has been an awful lot of confusion and, if you think about it, most people involved in infectious diseases are either hospital doctors, microbiologists, virologists or infection control nurses. They’re not necessarily – in fact they’re not trained in engineering generally, and so we have had a kind of two parallel universes come up with one group of people who are on the clinical side of things and mostly in the medical and infection prevention and control – which I’m going to call IPC after that – who have gone down one route and used one set of terminology, whereas those working in physics, engineering and aerosol science, I suppose, have used another terminology, and I’m from that camp, although I cross over into them.
So I will use – I’m afraid that’s the more correct terminology, by the way, from the physics, so I’m going to go with the physics. So that’s – there has been a lot of confusion, that’s all I’m saying.
Lead 3: We’re going to look at perhaps some of the ways that confusion plays out as we go through your evidence but can I start, please, with in your report you use the phrase “large droplets”. What is a large droplet, please?
Professor Clive Beggs: Right, first of all, to say droplets/large droplets, I’m using that term here, it’s my term for this Inquiry because people, especially from a lay background, need to know this – we’re talking the upper end of things and they’re above 100 microns, that’s micrometres, I’ll use the term “micrometres” or “microns”. It’s the same thing.
Lead 3: Is that the size of the particle?
Professor Clive Beggs: That’s the diameter of the particle but we abbreviate that to 100 microns. And there is a very good reason we’ll explain in a minute.
Lead 3: All right. So a larger droplet, in your terminology for this report –
Professor Clive Beggs: Is that, yes.
Lead 3: – is a particle greater than 100 microns?
Professor Clive Beggs: Yes.
Lead 3: All right. Just help the layperson, can we see a micron?
Professor Clive Beggs: A micron is a thousandth of a millimetre, so we can just about see those. You know, it’s about the thickness of a hair, I think. I think I read 50 microns is the thickness of a hair but it’s that type of order of magnitude. Yes, you can actually feel those droplets –
Lead 3: You can feel a larger droplet?
Professor Clive Beggs: You can feel a larger droplet, you know, when someone coughs on you or something.
Lead 3: In a nutshell, help us, how does a larger droplet behave once it’s in the air?
Professor Clive Beggs: Right. So from an engineering point of view and a physics point of view, it behaves ballistically and that means it’s like – “ballistic” means it’s got some mass, it’s got weight and, when you throw it – so it’s like throwing a stone. So it has a trajectory. So it’s got some velocity and mass. And if we’re talking in the context of respiratory aerosols, someone’s exhaled it, either coughed it or whatever, these are so large that they will fall rapidly to the floor, and they can’t go more than about 1 metre, 1.5 metres before they hit the floor. There’s something to do with evaporation but I’m sure we’ll come to that later.
Lead 3: I’ll cover that. All right, so the larger droplets behave ballistically, either they –
Professor Clive Beggs: Yes, ballistically, like a stone being thrown, that’s the way to look at it. They’ve got a trajectory.
Lead 3: Thank you. Aerosol particles, please.
Professor Clive Beggs: Yeah.
Lead 3: How have you defined them in your report?
Professor Clive Beggs: I’ve defined them and used the general understanding which has been around since the 1930s, really, in engineering and physics, with relation to the respiratory particles. They’re the particles that are less than 100 microns. Any particle of that size in this context is that. There’s not a strict actual – any demarcation for aerosols. It’s – the definition is to do with the behaviour and the characteristics.
Lead 3: Right.
Professor Clive Beggs: I’m sure we’ll talk about that in a minute.
Lead 3: So you told us how the larger droplets behave. What about the aerosol particles, how do they behave in air?
Professor Clive Beggs: Right, so the aerosol particles, as I – just to reiterate, are below 100 microns, right, and they can be various sizes down to very small sizes. The thing about an aerosol, by definition an aerosol is a suspension, a mixture of particles, and they can be liquid or solid or a bit of both, which is what you have with respiratory particles in air, in a gas, in air, and the really key thing is they float, they’re suspended, they’re floating in the air and the really important point is that they take on the – air is a fluid actually, you don’t think of it like that but it is, it flows.
They take on the fluid mechanics, the fluid dynamics of the overall fluid. So, in other words, wherever the air goes, the particles go if they’re an aerosol. That’s the definition.
Lead 3: Right.
Professor Clive Beggs: All right?
Lead 3: So, in short, they float?
Professor Clive Beggs: They float in the air, while they’re in that air, and therefore you can be interchangeable. Anything that’s aerosol transmission is airborne transmission, the two are –
Lead 3: Pause there. We have a stenographer who is taking a note and you’re also covering some quite complicated –
Professor Clive Beggs: Yes.
Lead 3: So I just want to try and break the answers down a little, if I may, and perhaps give slightly shorter answers and then we can ask for more information if it helps.
Professor Clive Beggs: Absolutely.
Lead 3: So larger droplets behave ballistically, they are 100 microns or greater; aerosol particles are less than 100 and they float in the air, in short.
Professor Clive Beggs: Yes.
Lead 3: Right. Okay.
You spoke about the 100 microns being, effectively, the dividing line between larger droplets and aerosols. Is that a general agreement about that dividing line at 100 microns?
Professor Clive Beggs: This is where the historical confusion comes in. Amongst physicists and people from my background, physicists and engineers, there’s a fairly – agreement from back in the 1930s, when this work was done. Shall I explain the – why the division is there at 100?
Lead 3: Yes.
Professor Clive Beggs: Yep. The reason that’s a division is that, as soon as – when you exhale particles, right – so I’m just going to call them particles, respiratory particles, both aerosols and droplets – they evaporate. There’s a lot of water in them so they immediately start to evaporate and they shrink down to about a third of their size and, basically – so if they’re less than say a 90-micron particle, that will end up at 30. In fact, there’s very little in that upper range, they’re down at 30 and below.
However, the particles that are larger than 100, they’re so big that what happens is they don’t have a chance to evaporate before they hit the ground, so that’s why the divide happens.
So this lot are kind of going down onto the floor, whereas the ones smaller, they can kind of evaporate and they then are wafting round the room on the air currents, basically, and they’re aerosols.
Lead 3: I think you said there that, where you used the phrase “respiratory particles”, you’re using it as a term that covers both the larger droplets and the aerosol particles; is that right?
Professor Clive Beggs: Yes, and the reason I – I’m just – to clarify that, when writing this report, I had to – as we will go on to explain, there’s a lot of confusion. I had to set out a framework and so it was extremely helpful just to refer to them as “respiratory particles” and that’s what I’m doing here, referring to them all as that, including everything.
Lead 3: We are going to come on to look at the way in which viral infections are transmitted, and obviously Covid in particular, but I want to just stand back for a moment and just get an overview of where we were at the start of the pandemic and where we are now in 2024.
If I ask you now in 2024 how is Covid transmitted, by which route I mean, what’s your answer?
Professor Clive Beggs: My personal answer and my personal opinion, predominantly by an airborne route.
Lead 3: Right, by an airborne route, by which you mean by aerosol particles?
Professor Clive Beggs: By aerosol particles, although obviously I’m not excluding other routes as well, droplets and other things involved, yeah.
Lead 3: So –
Professor Clive Beggs: That’s my belief.
Lead 3: – it transmits via airborne but it does also transmit via the droplets?
Professor Clive Beggs: Oh, yes, and contact.
Lead 3: Right, and then we’re going to come onto contact. In a nutshell, what is contact transmission?
Professor Clive Beggs: That’s where we start to talk about hand-to-hand contact, you know, someone, you know, coughing into their hands, shaking hands with someone, and then the other contacts are, for example, you cough, you touch a door handle, something we call a fomite, it’s an inanimate object, and then someone else touches that and touches their mouth or their eye or something. There’s a route of solid contacts in –
Lead 3: We’ll look at that in a bit more detail but they’re the three predominant routes that are in play for the purposes of transmission?
Professor Clive Beggs: Yeah, some people divide them up into subgroups – into different names but –
Lead 3: Don’t worry about that.
Professor Clive Beggs: Basically, that’s what we’re talking about: the aerosols, the droplets and then the contact routes, which include fomite transmission.
Lead 3: That is your opinion of how Covid is transmitted now in 2024. What was your opinion back in 2020 when the opinion started?
Professor Clive Beggs: It was airborne.
Lead 3: Fine.
Professor Clive Beggs: That was my opinion personally.
Lead 3: What about those who were advising, preparing papers, preparing IPC guidance, are you able to tell us what their view was back in 2020 as to how Covid was transmitted?
Professor Clive Beggs: Not the same as mine. The answer there is – I should have said, sorry – qualified my own belief – I believed it was airborne but I believed it was likely to be airborne, that there was a strong component. So when I say that, I’m not being exclusive, I’m saying that my belief is probably that it was airborne.
No, the general belief was that it was by droplets and contact and fomite transmission. That’s something which we’ll come on to. That was the general consensus at the beginning of the pandemic, which is why so much emphasis was on washing hands, and things like that.
Lead 3: So the position has, in fact, evolved from droplet being thought of as to be predominant in 2020 to now certainly, by 2024, if not earlier, the role of airborne transmission is now perhaps considered to be different and more important –
Professor Clive Beggs: Yes, the World Health Organisation is – realises now that airborne is – and the CDC – that it makes a significant contribution. There’s still argument over which is the predominant route, in various quarters but, you know, it’s shifted, the consensus has shifted considerably.
Lead 3: Okay. A little bit more background, please, about how respiratory viral infections transmit, and I think you say at your paragraph 14, as is probably obvious, that in order for an infection to spread –
Professor Clive Beggs: Yeah.
Lead 3: – the infectious individual must shed virus particles into the environment in such numbers thought generally to range from several hundred to many thousands, depending on the virus, such that a few eventually reach the target receptors of a susceptible host.
Can we put that into perhaps more easily explicable language?
Professor Clive Beggs: Yeah, I can easily do that, it’s a numbers game really. So we’ve got two ways of looking at this. The first one is a mechanistic thing. This is what we do as engineers and bioengineers, things have to get from A to B to cause an infection. So you can look at it in terms of the transmission route or routes. Someone’s got to produce some virus that’s viable that’s going to transmit through the environment somehow. This could be in the air, or it could be in the hands or whatever. Then it’s got to get to the target and the targets in this case are receptors, which I’m sure we’ll talk about later on –
Lead 3: Pause there. Just help us: in relation to Covid what are the main receptors?
Professor Clive Beggs: The main receptor with Covid is ACE2 receptors.
Lead 3: Where are they in the body?
Professor Clive Beggs: Predominantly the ones we’re most interested in are in the nasal cavity and also in the upper respiratory tract, the lining of the mouth, throat, but they do go down into the lungs. They’re also on the eyes, and I’m not so sure but I think also possibly on the lips as well, maybe there.
Lead 3: Pausing there, that’s, in short –
Professor Clive Beggs: But to a lesser extent, you know.
Lead 3: Pausing there, that’s in short as to how the virus Covid gets into the body, mouth, down the tract, in through the nose or in through the eyes?
Professor Clive Beggs: Yes, there’s got to be. It doesn’t do it by magic. Things have to move from one place to the other and they have to have some kind of vector, some transport. But on top of that, I think you asked me earlier on – if this is okay, or shall we leave this for later – the numbers game –
Lead 3: We’ll come to the numbers in a minute. I just want to set out some basics and then we can descend to the detail as we go through your evidence.
Professor Clive Beggs: Which – sorry, just to clarify, I think that was in there as well about the hundreds, and things like that. We’ll talk about that later, yeah.
Lead 3: All right. Can I ask, please, about one of the diagrams in your report and could we call up, please, page 10 of the report and figure 1, which might help bring this together. I think you’ve set out there how effectively the virus transmits. You’ve spoken there about aerosols and droplets and there’s various size of droplets on there.
Can you just help us, please, what are we looking at here with the person on the left, the infected person?
Professor Clive Beggs: Yeah, this is an excellent diagram which I use in my own lectures, but it’s not one I produced, it’s from a paper that sums up everything.
So just to – if you can see on the far left-hand side, you can see aerosols and droplets, and that basically tells you everything we’ve said already, the division, and they – it highlights that the droplets are not really inhalable and they’re larger than 100 microns, whereas the aerosols are inhalable.
So if we see the infected person.
Lead 3: Yes.
Professor Clive Beggs: Now, we’re actually seeing the whole respiratory tract there, the lungs and the upper respiratory tract and everything. That’s useful for maybe things we want to say later but, at the moment, we’re – that’s where the infection occurs.
Lead 3: Right, exactly, let’s just stick with the infected person then. You can see there that we’ve got there lungs and, indeed, you’ve highlighted – or the figure has highlighted the alveolar; is that deep into the lungs, in short?
Professor Clive Beggs: The alveolar are right at the bottom end, right at the far end of the lungs, that’s where the oxygen transfer goes on.
Lead 3: Right. We go up, effectively, through the bronchial, laryngeal –
Professor Clive Beggs: Yeah, the bronchial is the larger –
Lead 3: – into the person’s mouth.
Professor Clive Beggs: Yeah.
Lead 3: They may be sneezing or coughing here, it matters not, and out come the aerosols and the droplets?
Professor Clive Beggs: Yeah. We basically call – the kind of lower respiratory tract is basically anything below where the kind of mouth and nose is –
Lead 3: Right.
Professor Clive Beggs: – down into the lungs; and the upper respiratory tract is up from the larynx upwards. But, yeah, so this is where all the droplets come from. There’s a lot of fluid there basically in all that and, even when people are breathing, they’re producing aerosols. So I’m sure we’ll talk about that later on but that’s where they come from or originate. And if they’re infected, there’s a virus in there, and that’s going to come out, and once they leave the mouth or the nose, they’re in the room space and in the environment, which is the next part.
Lead 3: Pause there.
Professor Clive Beggs: Yeah.
Lead 3: We can see then that the infected person has coughed or sneezed or exhaled –
Professor Clive Beggs: Yeah.
Lead 3: – and the size of the droplets – and does the arrow pointing down to the bottom or the middle of the page indicate there effectively the ballistic way –
Professor Clive Beggs: Yes, that’s –
Lead 3: Can I finish?
Professor Clive Beggs: Yep, sorry, my mistake.
Lead 3: All right. Can we see there the ballistic nature of the droplets falling to the ground?
Professor Clive Beggs: Yes, we can.
Lead 3: All right. Can we also see there the aerosols, the smaller dots on the screen, floating across to the potential host, over a distance of about 1 metre, and then potentially going into the receptors on the potential host?
Professor Clive Beggs: Broadly speaking, yes, you’re right. At various sizes there’s aerosols. They are actually going more than 1 metre in this diagram.
Lead 3: Yes, they can keep going on the bottom.
Professor Clive Beggs: They can go a lot further than 1 metre, I can assure you.
Lead 3: Thank you.
Professor Clive Beggs: They are – yeah, they are then going into the receptors in the susceptible person, in the host.
Lead 3: All right. Help us, please, the aerosols, the smaller particles, where do they tend to end up in the potential host?
Professor Clive Beggs: They, what happens is that those aerosols are floating in the air. They’re various sizes, right, and they are inhaled if they come into the – in front of the face, they’re inhaled through the nose and through the mouth, depending on whether you’re mouth breathing or nose breathing, and what actually happens during respiration is you exhale out and so, when you’re exhaling out there’s actually a jet of air coming out and it’s blowing away little aerosols, and then when you inhale, which we call aspiration, we take a breath, through the nose, actually the air velocities can be quite large, they can be between 10 cm to – up to 40 cm per second and these capture the aerosols that are in that area, that’s both through the mouth or the nose, depending on the rate of breathing, right, and how wide your mouth is, and those capture them and the air sucks in and the aerosols go in and then they impact in various parts. The smaller ones tend to go deep into the lungs, into the lower respiratory tract, whereas the larger particles, over 10 microns, definitely stick around up here.
Lead 3: All right. So we’ve just looked there at how the infection gets into the potential host. I just want to ask you this: where, in relation to Covid, is it your view that infectious particles are generated in the infected person? If it helps you, I’m at paragraph 26 in your report on page 13.
Professor Clive Beggs: Well, I think I can probably answer it anyway but – without looking to it. I think I’m just going to fly blind.
Particle sizes – it used to be thought that it didn’t matter where the particles were generated. Now we understand that the particle sizes in the aerosols actually reflect where they’re generated in the human body. So the smallest particles are actually generated deep in the lungs because there’s a kind of fluid lining to the lungs, and something called – a technical thing called a film burst, when you breathe out, and that’s just even in breathing, and you produce these tiny aerosols and these are kind of like 1, 2-micron size, they’re really small.
The other place where you get smaller aerosols are often around the vocal chords there as well. They produce slightly bigger but they’re also 5 micron, maybe below 10 micron, they can be a range of sizes, so the fluid there.
The largest particles are generated in the actual mouth and they’re saliva, that’s where the big ones, the over 100 microns.
So actually the particle size reflects where they’re generated and now we know also that the microbes, if they’re bacterial or viruses, in them tend to reflect where they’re generated, so –
Lead 3: So the question I asked you was –
Professor Clive Beggs: Sorry.
Lead 3: – where in relation to Covid were the infectious particles generated?
Professor Clive Beggs: Good question. The answer is not 100% clear cut but I would say mostly in the lungs, deep in the lungs and in the vocal chords, although we can’t exclude that some other virus might be in the larger droplets as well.
Lead 3: Understood, thank you very much.
Professor Clive Beggs: But in the lungs and the vocal chords, those are key areas, as I’m sure we’ll talk about later on, the vocalisation, yeah.
Lead 3: Can you help us with whether it’s the droplets or the aerosols that are more likely to contain Covid or not, which of the two?
Professor Clive Beggs: It’s the aerosols that are more likely. There’s a reason for this, and it goes back to – it’s a change in thinking, but we’ll talk about that, I’m sure, later on when we talk about this stuff.
Lead 3: Now, how one –
Professor Clive Beggs: It’s in the small droplets, that’s it – no, small aerosols. Small aerosols.
Lead 3: Thank you, all right. So deep in the lungs, small aerosols, that’s where the Covid –
Professor Clive Beggs: And the vocal chords.
Lead 3: And the vocal chords, all right, thank you.
Help us with how people generate the respiratory particles. Obviously with breathing, what about coughing or sneezing?
Professor Clive Beggs: Yeah, right, so we get – let’s go from the kind of least violent, the breathing. So people didn’t realise this before but we are emitting – I’ll give you a figure – over 100 small aerosols per second in just breathing. You can’t see them but every one of us is producing that now. Right? So they’re not insubstantial. So even with just breathing, you produce thousands of these things and hundreds of thousands of them in an hour.
The next level up, talking. You’re bringing in the vocal chords now and they vibrate, they produce aerosols. Off the top of my head, I can’t remember the –
Lead 3: Don’t worry.
Professor Clive Beggs: But it comes, it’s an appreciable increase. But the louder you talk, shouting, more gets produced. So if you’re in a loud noisy situation, you raise your voice: more aerosols.
Singing particularly lots of aerosols. There are nearly up to – I think a figure sticks in my head of about 900 aerosols per second.
Then we go to the things that we – the kind of symptomatic coughing and sneezing.
Lead 3: Yes.
Professor Clive Beggs: They’re slightly different in the sense that when you have a cough and especially a sneeze you get a violent action and that brings in the whole of the system and that strips out more – so you get a wider range, you get larger droplets produced in those things and a lot of droplets in – a lot of particles in between. That’s the – how it works.
Lead 3: Can I just touch on evaporation, because you’ve told us about the respiratory particles being made up of water, which clearly evaporates. If it helps you, Professor, I’m around paragraph 30 on page 15 of your report, but I think so you say this:
“… no matter [what] their size, all respiratory particles comprise mainly of water, because they’re formed in the lungs, throat and mouth …
“… as soon as the particles exit the mouth or nose and enter drier air, they immediately start to lose water due to evaporation and dramatically shrink in size to about a third of their original diameter.”
Help us with the droplet and the aerosols and how they evaporate?
Professor Clive Beggs: Right. You know, I’ve done plenty of modelling of this over the years in my own work. You’ve got to understand that a small particle has a small mass for a very large surface area, you know, think of a small – you know, we’re talking balls, from like football, the large one, going down to kind of like, you know, marble size or whatever. So the relationship, as you get smaller, the surface area is much greater to the mass. So you evaporate through the surface area.
So these poor small aerosols, small particles, they’re losing them even faster, so they’re going right down. They’ve got moisture in there – they’ve also got proteins and other solids in there – so they evaporate down into these things, right? Whereas the larger droplets, they’ve got a small surface area in comparison to their mass, so the evaporation is less with the larger droplets, hence why they struggle to evaporate before they hit the ground. But, generally speaking, the kind of rule of thumb – and that’s why we – to make sense of this, around about a third of their size, that’s a good rule of thumb.
Lead 3: Can I just see if I’ve understood this correctly: is it the case that the aerosols evaporate quickly?
Professor Clive Beggs: Rapidly, yes, within –
Lead 3: Right, but the larger particles don’t evaporate before they hit the floor?
Professor Clive Beggs: Yeah, simple, that’s the general overall thing, and the ones that evaporate go to about a third of their size.
Lead 3: Right, understood. But the smaller particles, the ones less than 100 microns, presumably they can become still suspended in the air and float around?
Professor Clive Beggs: Absolutely, yes, I mean, just to clarify one point, just to give an illustration –
Lead 3: Please do.
Professor Clive Beggs: – if you produce an aerosol, so say you had, you know – it doesn’t mean that you’re at 100, you know, it’s a whole gradation of things coming out of the mouth, you can have something at 10, something at 20, so if you had a 15-micron particle, that is so small, in comparison to its large surface area, it’s going to have evaporated down within, you know, a few centimetres from the mouth. It’s done its evaporation and it’s a small particle moving around, so it’s very rapid.
Lead 3: I think you said in your report at page 16, paragraph 37, that historically many people concluded wrongly that the vast majority of exhaled viruses would be contained in the larger droplets, which were assumed to travel no further than about 1.5 metres but, over the years, that assumption has been shown to be incorrect.
Professor Clive Beggs: The answer is yes. Shall I elucidate on it?
Lead 3: Yes, what I want to try and understand is why that’s important for us to be aware of that historical misunderstanding, if that be the right phrase, and how it affects Covid and the transmission of Covid.
Professor Clive Beggs: It’s absolutely fundamental because it’s a bit like a house of cards: once that goes, everything else goes, so it’s crucial – that’s a crucial and important factor.
Can I just elucidate on it?
Lead 3: Please do.
Professor Clive Beggs: Right, so, and it’s a perfectly logical position to hold this, by the way, and I used to believe it myself, right? That was my understanding, so it’s reasonable to appreciate this.
So when you look at all those droplets and aerosols, all the respiratory particles that come out of the mouth during, let’s say, a cough, for example, right, an exhalation event, a cough. So if you added them all together, you would have a bulk of fluid, right, and we know that the virus is in that fluid, right?
But, actually, if we looked at the quantity of the fluid, if you think about it, the actual volume of the fluid, most of that fluid, kind of 90% of it, is actually in particles that are over 10 microns in diameter. The bulk of the fluid is in the big droplets, right, which you think, well, what’s the point of that, until you go to the next stage.
So where’s the virus likely to be? And we thought that the fluid was all the same and we thought – we didn’t understand completely that the virus reflected where the sites – where they were generated. We thought that it was just evenly distributed through the whole of the fluid. So that meant if most of the fluid was in the large droplets then most of the virus must be in the large droplets.
So, historically, those involved in infection prevention and control and public health, and you will see it as we’ll talk in other documents, made the assumption, and many scientific papers made the assumption, that the bulk of the virus was in those large droplets that don’t travel very far. Now, that is not the case.
Lead 3: Right.
Professor Clive Beggs: But that’s only been discovered in the last ten years or so, 10/12 years, right, as the science improved. But we will I’m sure talk about that.
Lead 3: Right. My Lady, can I interpose at this point to say this: Professor Beggs has very helpfully in his report set out key findings which summarise a number of paragraphs and pages, so if anyone is either struggling to follow or wants to have a quick easy reference guide, the key finding boxes are very helpful in drawing all of this together. So can I just put that advert out there, if I may, in an attempt, I hope, to help anyone who is following online in particular.
Can I just ask you this, please, Professor: is there any scenario or situation in which someone could produce a droplet without also generating significant amounts of aerosols?
Professor Clive Beggs: No.
Lead 3: No. When we think about Covid, can I ask you, please, about what you’ve termed “virus shedding”, and I’m at paragraph 38 in your report on page 17. Just in layman’s terms, what’s virus shedding?
Professor Clive Beggs: Right, so in the context of that diagram we’ve just seen there, so if it’s not clear, the latest science is that the bulk of the virus is in the smaller aerosols, right, the under 5 microns, I’m sure we’ll mention that later, but that’s the case, the bulk of the virus is in the smaller aerosols, not in the big droplets. That’s the evidence now. That goes for both influenza and Covid.
Lead 3: All right.
Professor Clive Beggs: Right, so now virologists talk about virus shedding, what they’re meaning is – this is getting back to the numbers game – it’s the quantity of virus that’s shed by any route. So this could be, for example – well, it comes out of somewhere, out of the mouth or the nose, but they don’t just mean in the aerosols, they mean you can cough in your hands and then touch something, the virus can be wherever it is.
So when they talk about virus shedding, they’re talking about the number of, rather confusingly, virus particles which are even smaller, viruses, and these are viruses – they look to see – they do it by various means but, anyway, virus shedding is basically just the number of viruses that are just kind of released by an infectious person, by whatever means.
Lead 3: Now, in relation to Covid, obviously there may be a period of time where you are infectious but you don’t know that you are. Right?
Professor Clive Beggs: Absolutely.
Lead 3: Asymptomatic, as it’s sometimes called. There’s also the presymptomatic period.
Professor Clive Beggs: Well –
Lead 3: Help us with those and what you say at paragraph 38, please, in your report.
Professor Clive Beggs: Absolutely. You’ve led me nicely to the right point there. Right, when you come into contact with someone who is infectious, so they may not appear infectious, they may not be coughing, that’s, you know, they may be perfectly all right, they don’t realise they’re infectious, and that’s what we call asymptomatic. They don’t show any symptoms, right, but they’re still infectious.
However, when you meet them, you don’t know whether they’re – they’re not showing any symptoms but in two or three days’ time, they may get very, very ill and feel really unwell and stay at home. Actually, they’re asymptomatic at that time but they go on to develop symptoms, so we say they are presymptomatic.
So, strictly speaking, “asymptomatic” refers to people who never show any symptoms but it’s a kind of loose thing, it overlaps with presymptomatic. It’s a working term for – it can include presymptomatic people, I would use it in that way. So, in other words, I would say it is people who appear to have no symptoms and are still infectious.
Lead 3: Right. So that period of time when you don’t know you’ve got it, in short, because you feel all right –
Professor Clive Beggs: Yeah.
Lead 3: – help us there, please. I think that’s when you say in your report that that’s when the individual is most contagious?
Professor Clive Beggs: Yeah, the most contagious period is shortly before they become symptomatic, if they do become symptomatic, and for that two to three days beforehand and shortly afterwards, I think is also fair to say. It then starts to subside, the infectivity, after their symptoms develop. Is that – is that all right?
Lead 3: Yes, thank you. So it’s a dangerous situation where people are walking around, feeling well but could in fact be transmitting the virus?
Professor Clive Beggs: Yes.
Lead 3: All right. I think you said in your report that the virus was able to spread for maybe two to three days before any symptoms develop but with Covid there were variations between the various strains in how long people were incubating the virus for?
Professor Clive Beggs: Yeah, I think – right, so in that paragraph there, I use the term “incubation”. So incubation is not quite the same as shedding. Incubation is from the minute you first get infected. At that point, you’re not shedding that much virus because you’re not that infected. You know, you are infected but it hasn’t had a chance to replicate in your body but, as it starts to replicate, then you become infectious.
So for – I think the original figure that I’ve got down here, the figure that sticks in my head is four to seven days, I think that’s for the original strain, the Wuhan strain of the virus.
Lead 3: So you’ve got 4.6 to 6.4 days –
Professor Clive Beggs: Yes, four to seven days, it sits there. But for the subsequent waves, the delta, the omicron, they’ve found the incubation periods were shorter, so it came on quicker.
Presumably then, also that would mean that the – a similar type of period of asymptomatic or presymptomatic infection, but I’m not an expert on that so I’m going to say that I’m on dodgy ground there. But you certainly will have exactly the same – you’ll have a presymptomatic period where you’re not showing symptoms and you’re still shedding.
Lead 3: So whatever time you’re incubating the virus for, there is a period of time, potentially, where you are contagious and you don’t know you’re ill and, therefore may not be wearing a mask, may not be hand washing, may be in close contact with people, all of the ways in which the virus could easily spread?
Professor Clive Beggs: Yes, and you may be singing, which –
Lead 3: Right.
Professor Clive Beggs: – you know, is not a good situation.
Lead 3: Can I just deal with a few more questions, please, about asymptomatic transmission and then perhaps we’ll take a break, if we may, my Lady. Thank you.
It helps you, Professor, Can I turn you please to page 22 of your report. Your “Key findings” box at the top of that page may be the easy way into this. Thank you very much. It may be the easy way into these few questions.
I think you set out there that:
“A third to half of all Covid-19 cases are asymptomatic …”
Professor Clive Beggs: Yeah, my understanding – in fact it varies by age group. So in children it’s even higher than that, and young people. But in older people and elderly people, it’s much less than that. So it kind of balances out. About 30 to 40% is the kind of figures that I see are asymptomatic. Yeah, that’s, I think that’s reasonable to say.
Lead 3: Then you go on to say there that:
“Although asymptomatic transmission of [SARS or Covid] is a widespread phenomenon, early in the pandemic it was not known to what extent it occurred. SAGE regularly reported on the gradually strengthening evidence base and by September 2020 confirmed definitively that it was occurring.”
Professor Clive Beggs: Yeah, it’s a really tricky one, this, in the sense that, you know, what do we mean by “asymptomatic transmission”, is this people who were asymptomatic all the way through or presymptomatic and that was a blurring line, so it makes it very difficult, but they were aware early – you know, in the SAGE minutes that I’ve seen, they were discussing it and they were aware that this was a potential problem. But they didn’t know the extent to it, and there’s a BMJ article, I think, in December of that year, that is saying we still don’t know the magnitude of it. But, certainly by the minutes of the meeting in the September, this was becoming – you know, it was firming up.
Lead 3: I think it’s important to point out, isn’t it, that asymptomatic infection does not necessarily lead to asymptomatic transmission; is that correct?
Professor Clive Beggs: Yes, except for, of course, we’ve got the problem of presymptomatic is asymptomatic at the time, so it’s how you define it. So it doesn’t always – there is some evidence that some people who never develop symptoms have a lower viral load, so they’re less infectious but, of course, that person who you meet at work or whatever, who doesn’t show any symptoms but has Covid, you don’t know whether they’re presymptomatic or asymptomatic, so it’s a very blurry boundary, that’s what I’m saying.
Lead 3: Finally, in those key findings, asymptomatic transmission of Covid accounts for many of the infections acquired in hospitals, and we’ll probably hear more of that, my Lady, with the IPC trio next week.
Professor Clive Beggs: Yeah. I was going to mention that, because not being a clinician and, you know, I read the papers and I’m aware of this and I was asked to comment on it, but the clear evidence from what others have reported is that asymptomatic transmission, both amongst healthcare workers and patients, made a major contribution to transmission in hospitals and other healthcare environment –
Lead 3: Just the final bullet point there, before we take our break: you reference there that there is some evidence that flu can also be transmitted by asymptomatic people who are infectious. Why have you made reference there to flu when predominantly we’re talking about Covid?
Professor Clive Beggs: Right, throughout this, I was given a brief to look at the transmission of infection and you can’t – if you’re looking at pandemic preparedness, it was all around influenza. Influenza and I would also put RSV, another respiratory infection, the mechanisms of transmission are all very similar. The viral agent’s different, so it makes sense to look at them, so I have looked also at influenza, I was asked to look at influenza and, as I was doing that, I was asked by the Inquiry to look at the asymptomatic transmission of influenza, which I have to confess I’d never looked at, and so I dug down into the information.
So I don’t claim to be an expert on asymptomatic transmission of influenza but I looked into the evidence base and it was interesting because there were some contrasting views but the overall consensus was that, yes, it does occur but not to the same extent as with Covid, right? So that’s why I looked at it.
Lead 3: Is the point there perhaps being made that, if the planning was based about flu and flu could transmit asymptomatically, those that were looking at Covid and drawing parallels with the flu planning might therefore have thought more quickly, “Ah, well, asymptomatic transmission could also be a route in relation to Covid”?
Professor Clive Beggs: That is a very, very obvious and logical and reasonable stance to take. I think, you know, when I looked at the evidence for asymptomatic transmission of influenza, I very quickly dug up papers that were showing quite large similar types of levels to Covid and then, as I looked at them, I suddenly realised there was a large controversy about this and that some people were criticising the methodology. And when you actually looked at the methodologies and trying to decide what was presymptomatic and what’s asymptomatic, that’s the big problem, it came down to a figure – I’m sorry, off the top of my head I can’t say, it’s in the report, but 15% sticks in my head. But I don’t know whether that is the case, right, so without looking, reading it –
Lady Hallett: You said that a consensus developed that flu can be asymptomatic; when did that consensus develop, it having been controversial?
Professor Clive Beggs: Right, have we – let’s just –
Lady Hallett: Very rapidly.
Professor Clive Beggs: I’ve got it –
Lady Hallett: Is it before the pandemic or not?
Professor Clive Beggs: Oh yes, before the pandemic, I think it is anyway.
Lady Hallett: Don’t worry. That’s –
Professor Clive Beggs: Sorry, I’m searching through my text here.
Ms Carey: May I make a suggestion, that we take a break?
Lady Hallett: Yes, we’ll take a break and you can confirm after the break.
Professor Clive Beggs: Yes, I can certainly do that, yeah.
Lady Hallett: Right, we’ll take ten minutes.
Ms Carey: Thank you very much, my Lady.
(11.50 am)
(A short break)
(12.00 pm)
Lady Hallett: Ms Carey.
Ms Carey: Thank you.
Before we had our break, I think, Professor, you were just answering some questions, indeed one from her Ladyship, about the evidence that flu can be transmitted by asymptomatic – and we left it on a cliffhanger, that you were going to go and look it up.
Professor Clive Beggs: Yeah.
Lead 3: Could we turn, please, to paragraph 53 –
Professor Clive Beggs: Yeah.
Lead 3: – within your report.
Professor Clive Beggs: Right, well, I said 15%, it was 16%, so I wasn’t far off.
Lady Hallett: I’ll let you off.
Professor Clive Beggs: But I think the first point there is it’s not clear-cut by any means. Difficulties are because, frankly, how do you know who’s truly asymptomatic and how much are presymptomatic. But you can see the dates here, right at the top, the first sentence, it says:
“Most cases of seasonal influenza are thought to be asymptomatic.”
And that was someone – Hayward in 2014. However, that’s disputed by various people and various things and methodologies and everything. And this comprehensive – so we’re down at about line 5 or 6 – a comprehensive meta-analysis in 2015 said really that’s 16%. And that’s Leung in 2015. So it was definitely there.
But the key point, at the bottom, just to get it over, is of course those people, if they’re lower infectious and fewer symptoms, they mix more, so whether they were transmitting more depends on not only how ill they were but also how much they mixed, shall we say.
Sorry, I’ve added that on.
Ms Carey: No, don’t worry, because I think what I just wanted to try to be clear, and I know this will resonate, my Lady, with evidence you’ve heard, I suspect, in Modules 1 and 2, I think there was a pre-pandemic flu strategy in 2011, and we’re going to perhaps look at that little later with Professor Beggs, so there is the underpinning document in 2011 and then these various studies in 2014, 2017, 2015, et cetera, albeit not consensus on that either, that suggested though that flu was thought to be asymptomatic. So we’ll just keep that chronology, if we may, in our minds as we go through.
Professor Clive Beggs: Can I just clarify –
Lead 3: Yes.
Professor Clive Beggs: – what I’m saying here? It was known that some influenza transmission was asymptomatic before the pandemic.
Lead 3: Yes?
Lady Hallett: And the dispute was on how many?
Professor Clive Beggs: How many.
Lady Hallett: Yes.
Professor Clive Beggs: And it was to do with methodology.
Lady Hallett: So I can confidently say that it was known that some cases of flu are asymptomatic?
Professor Clive Beggs: All I’ve reported is what was in the papers, and that’s what was said –
Lady Hallett: Thank you?
Professor Clive Beggs: The references are all there.
Ms Carey: Thank you very much, Professor.
New topic if I may, please – and in your report, if it helps you, we’re at page 24 – and I’d like to examine with you, please, the movement of infectious particles through the air.
Now, we’ve probably touched on it a little bit by looking at the ballistic way that the droplets behave in contrast to the way that the aerosols float through the air – my paraphrasing, I appreciate – but there we have, I hope, at the top, a little summary of that:
“Exhaled respiratory droplets [greater than 100 microns] behave ballistically … fall … to the floor …
“Smaller … particles … shrink … due to evaporation …”
As we’ve looked at:
“… and become [even smaller] aerosol particles which can float in [the] air.”
Now, help us, please, you say:
“These small aerosol particles can take many minutes (even hours) to settle out of the air and therefore can be transported long distances around [the] rooms by air currents.”
Professor Clive Beggs: Can I direct you – can we put it up? – direct you to paragraph – table 1 in paragraph 59.
Lead 3: Yes, I’m going to come on to that, but if it helps you to answer the questions, please do. Because what I really wanted to know was: how long does it take? How far can they go?
Professor Clive Beggs: That’s what I was going to do.
Lead 3: All right.
Professor Clive Beggs: That’s where the table would be – that’s it, thank you.
Right. Back in 1851 a guy called Stokes developed a whole load of laws to do with – basically it was understood how aerosols behave, right, and how particles in air behave, and we use them in engineering to predict how aerosols behave, and basically Stokes’ law can be applied both to moving particles but also to particles in still air.
And here, what we have here is a table for various sizes, and I just did it for illustrative purposes, a range of sizes, and I’m assuming 2 metres, which is the height of a tall person, producing – but it’s an approximate height – and you can see there that – say we take a 5-micron particle.
Lead 3: Yes.
Professor Clive Beggs: That actually takes – descends at about – well, it takes 32 minutes to fall to the floor.
Lead 3: Right. So if someone were 2 metres tall –
Professor Clive Beggs: Yeah, it’s a bit high, but height of a –
Lead 3: Yeah.
Professor Clive Beggs: 32 minutes, right? So we can set the clock and we can wait until half past and it’s still falling. And that’s in an absolutely still room. This room and every other room that you will be in has movement, because basically if you have a mechanical system – we’ve got lots of movements in here, but when people move – walk around – and we’re each producing what’s called a thermal plume, because we’ve got – we’re warm and we have a convective – so there is lots of air movement, so they will stay airborne for a lot longer than this.
Lady Hallett: Can I just interrupt to say the transcriber’s software has crashed, but they will catch up on the transcript.
Ms Carey: Thank you very much.
So you mentioned there the thermal plume. Help us, where is it? What is it? How does it work?
Professor Clive Beggs: Oh, right, yeah, it’s been overlooked a lot.
Yeah, thermal plume, basically your skin is at about, I don’t know, 36, 37 – 37 degrees, the air’s at 20 degrees, when it comes into touch – into contact with you, you’re warm and you get – you’ve got – every one of us here has got a rising current of air, convective current of air, passes over the face, round the back of the head, and you’ve got a big plume – and we can actually visualise this –
Lead 3: Pause there, because there may be a diagram that helps you.
Could I call up, please, figure 7 on page 26 of the report, because I think this will demonstrate what you’re – so there’s a person at the bottom?
Professor Clive Beggs: Yeah, this is my colleague at Queen Mary’s in London.
Lead 3: Right. And the halo, for want of a better phrase, is that the thermal plume?
Professor Clive Beggs: It is, yeah. What we did there, this is something called Schlieren photography, which is a very specialist type of photography which is useful in this situation. The horizontal line, by the way, in this particular – is us trying to simulate a ceiling, right?
Lead 3: Okay.
Professor Clive Beggs: So what actually happens, and we’ve got a video of this online, you can see that we had this constant flow of streams of air going up. They get to the ceiling and then they spill out across the ceiling, depending on the height of the ceiling of course, and you can see – it really is quite – they could be kind of moving at the highest above the head at about, you know, 30 centimetres, a foot, a second, and that can transport quite large aerosols up.
What we think is happening, anything that gets entrained into that goes up to the ceiling, then fans out and then after a while it gets slowed down and the heavy particles fall out. But it can also go for radiators, you know –
Lead 3: I was going to ask, yes?
Professor Clive Beggs: – they can do the same thing, it’s an area that’s not – it’s the big difference between indoor transmission and outdoor transmission. It’s one of the key differences.
Lead 3: Right.
Professor Clive Beggs: Outdoor it just goes up and it’s distributed.
Lead 3: Right. So the virus can go up in the particles, up through the – upwards through the thermal plume, and then into, presumably, any current of air that is within the room?
Professor Clive Beggs: Well, in fact, here we’ve got what we call four-ways movement diffusers, they’re – something called a Coanda effect, they’re shooting air underneath the ceiling, so if someone is producing a thermal plume that then mixes with that and there’s particles in it, they will be distributed around.
So this idea – it’s very complex, it’s complex fluid mechanics, and it’s different in every space, but this idea that we can just say a particle falls out of the air very quickly, you know, by its size, it depends what it comes into contact with. And this is the problem.
Lead 3: Can I see if I understand this correctly. Your thermal plume sitting there will travel upwards?
Professor Clive Beggs: Yeah.
Lead 3: And on a current could, therefore, flow in the direction of her Ladyship, me, everyone else –
Professor Clive Beggs: Yeah, it could do. Obviously the smaller particle – the heavier the particle – the point about the aerosol is that it will only – the particles will only stay suspended in the air until the air current drops in its strength, at which point they start to descend, but they then fall into the next – they kind of do that (indicated), you know, but they go a lot further.
So the table in table 1 is an ideal situation in still air.
Lead 3: Yeah.
Professor Clive Beggs: And unfortunately I’ve seen in lots of literature people saying – the worst case is they say, like, a 5-micron particle can’t go more than a metre, which is just wrong, but people sometimes take a value off here, but rooms are not still, that’s the whole point. That’s the bit that I’m trying to get over.
Lead 3: Are you able to help us with how far, in metres or whatever metric you wish to use, an aerosol can travel? In a room like this perhaps, might be the easier way of thinking about it.
Professor Clive Beggs: Yeah, they can travel a long way, much further than point of view, and where we – we’ll talk about near field and far field. But if we could look at figure 8, please.
Lead 3: I thought you were going to turn to that.
My Lady, it is behind tab 8 and it is INQ000497038. This is going to be, when we get it on screen – there we are.
Professor Clive Beggs: Oh, right, yeah, that’s – I didn’t think that was figure 8, actually, but it doesn’t matter, this is good as well.
Lead 3: Just do it with this – well, this one is in the context of a six-bed bay –
Professor Clive Beggs: Yeah, this is very good. Figure 8 in the report was actually also computational fluid dynamics.
CFD stands for computational fluid dynamics and its’ a tool that we use, physicists and engineers use, to simulate complex flows of air and particles and fluids in various environments.
And this is actually work that we had done at Addenbrooke’s, I worked with the Addenbrooke’s team there, at Addenbrooke’s Hospital, and this is – similar – is one of the wards there, where you have a classic six-bedded bay. And what happens is we used
some – a team of aerodynamicists used computational metres. Right? That’s from the social distancing 2 fluid dynamics to simulate the transmission of aerosol
particles.
And there we have a bed – the dark bed on the
right-hand side in the middle of the six-bedded bay is
a patient who is infectious. We can’t see the thermal
plume here – they’re lying in bed, they’re exhaling
out – and this is actually 2.5-micron particles, and we
built in the thermal plume. And what you see is the
density of the particles after ten minutes in that space
of regular breathing out and exhaling particles, and you
can see them migrating all the way through.
And in fact as part of the studies we did at
Addenbrooke’s, we looked at the particles and we could
see them migrating throughout the whole ward within
minutes. You know, it takes time, that’s what
I’m trying to say. They can transmit 10 metres easily.
Lead 3: So although this is a simulation of a six-bedded bay,
one can see there that not only is there the infection
concentrated around the infectious patient but the two
beds either side of the infectious patient, and indeed
the aerosol beginning to spread out to the other three
patients and up to the top of the bay –
Professor Clive Beggs: Into the corridor, that’s the corridor towards the
nurses’ station.
Sorry, you said a simulation there. This is a simulation –
Lead 3: Yes.
Professor Clive Beggs: – but in fact, just to clarify that and – we also did measurements, we had particle counters throughout the whole ward – now, these are not looking at bioaerosols, they’re just looking at particulates – throughout the whole ward. And in an earlier study we actually measured the transport, and we’ve published this in the Journal of Hospital Infection, and what we found was, for example, when the ward round came round, we saw the particles go up in one part of the ward, you know, 10, 15 metres away at the far end, and then those particles just migrated all the way through – as with the ward round, as the doctors went round, but also as the air currents moved. Which is exactly what we’re seeing here.
Lead 3: Thank you.
Professor Clive Beggs: It’s not just simulation.
Lead 3: No. Understood.
Perhaps if we just take that diagram down, please, because it brings me on to inhalation and the risk of inhalation.
And if it helps you, Professor, I’m at paragraphs 65 onwards in your report, which is at page 28.
Professor Clive Beggs: Yep.
Lead 3: Just give me a moment to turn that up.
(Pause)
Lead 3: It’s probably evident, just looking at the key findings first of all, that when aerosols are inhaled the different size particles land in different places within the respiratory system. Right?
Professor Clive Beggs: Mm.
Lead 3: The smallest particles, which as you told us before the break are more likely to contain the virus, they tend to travel deep into the lungs, while the larger aerosol particles land in the mouth and throat?
Professor Clive Beggs: Yes. But – yes, shall I –
Lead 3: Do you have a caveat to that?
Professor Clive Beggs: Yeah. There is no clear cut-off, right. So historically, the kind of – which comes back from almost the end of the Spanish flu in the First World War, you know, the early part of the 20th century, so it’s pretty old science, but it was realised then that particles that were less than 5 microns tended to travel into the lower respiratory tract. What that means is that they went deep into the lungs.
Particles above that size that were inhaled tended to stick in the nasal cavity, in the upper respiratory tract.
And clinicians use that as a demarcation to do with TB, it was – TB went down in the lungs, they thought that was small microns, whereas things like influenza, which predominantly infects the upper respiratory tract first and foremost, they thought: well, that must be in particles bigger than 5 microns. And we’ll come on to that later.
But the truth of the matter is it’s a gradation. It’s roughly around there but it’s kind of 10 to 5 microns. 10 microns can go deep into the lungs as well, and some 5 microns can stay up in the upper respiratory tract, but the important point there is that particles in inhalation up to 100 microns can be inhaled if the air’s strong enough to – if they’re in the region, they can – but they don’t go deep, they just stay up here.
But most of the particles that are being inhaled and tend to end up somewhere in the system are under 20 microns, that’s the general rule. But it’s not hard and fast.
Lead 3: No, understood, all right.
Now, I think you said, though, in your report at paragraph 66 that:
“Aerosol particles tend to be light and slow moving, and as such are easily inhaled.”
Professor Clive Beggs: Yes.
Lead 3: “… if a susceptible person is close to an infectious person then there is the potential for droplets transmission via the eyes … or mucus membranes of the nose and mouth …”
Is that correct?
Professor Clive Beggs: Yeah. Yes. I’m just trying to see this. Yeah.
So the – this is about droplet transmission, the larger droplets, right?
Lead 3: It is.
Professor Clive Beggs: So we’re talking about larger than 100 microns. They can’t travel very far. So if someone’s in close proximity to someone else, within a metre, say, and someone coughs or sneezes and they’re infectious, they’re going to produce a whole load of aerosols and droplets but those droplets have got a trajectory and they’re ballistic, and they can land – we all know it, we’ve all experienced it when someone’s coughed or spoken, you can feel the spit, you know, on your forehead – that’s a very large droplet, but they could land on your eye, and there’s some ACE2 receptors there, or sialic receptors with influenza. And that could cause an infection, a route of – what we call a portal of entry. Or, and it’s a bit more ambiguous on this one, it could land on your lips, for example. It could land on – that’s trickier. In my opinion it’s trickier, but traditionally it’s thought –
Lead 3: Pausing there, if we just think about it –
Professor Clive Beggs: That’s the droplets, not the aerosol.
Lead 3: I know. If we just pause there and think about it in the context of a nurse taking a vital sign, blood pressure or temperature in the ear, essentially what you’re saying there is that the droplet, the larger particle, can easily, if they’re up close to them, end up in the eye, or in the mouth, albeit that you’re –
Professor Clive Beggs: Absolutely. Well, I personally find it harder to see how it gets up the nose, because what’s happening is these droplets are tending to fall away, and they’re large so they can’t really be inhaled very easily, so they’re moving away, they’ve got momentum, so they’re not being drawn in. But certainly on the eyes. But they could land on the lips.
Lead 3: So if the nurse –
Professor Clive Beggs: Maybe on the nose and someone could touch them and then pass it on, rub their eye or something.
Lead 3: So if the nurse is not wearing a goggle or a visor, that’s an easy route –
Professor Clive Beggs: That’s an easy route for that – I’ve got to say, sorry, it’s a route, but the epidemiology supporting this is not actually that strong. Because when I looked at it, this is what is supposed to happen, and it’s plausible, definitely.
Lead 3: Now, let’s look at the aerosol particles and your paragraph 67, and you say that because they are suspended in the air, the quantity that will be inhaled is directly proportional to the concentration of the particles in the air and the volume of the air that is inhaled.
So take a slightly different example now, the nurse is not taking blood pressure or the temperature but is on the other side of the room dealing with another patient, help us please with what you say there and the level of risk to the nurse.
Professor Clive Beggs: Yes, I will, but I want to just say one thing in relation –
Lead 3: Of course.
Professor Clive Beggs: – because it’s important to do this.
So let’s make the nurse, again taking blood pressure in the same position as the droplets, you can’t have droplets without aerosols. So if that patient – if that nurse has got no mask on, for example, they may receive a droplet in the eye, it’s a fairly small target, but they’re more likely to get a face full of aerosols and inhale those into the things. In my opinion, that’s a higher likelihood. So in that near field they can get that. But of course aerosols don’t just stop there, they pass on further. So now we go to the longer range thing that you’ve just described. So –
Lead 3: We’re going to look at near field and far field, so it is as well to deal with it now.
Professor Clive Beggs: Right, so going back to the concentration of the particles, it’s irrespective, from the aerosol point of view, of whether it’s in the near field or the far field, near or further away, you breathe in some air which has some virus in it, viral particles. So it’s actually – just the number of viral particles is – the risk is related to the – this is the numbers game: the more viral particles you inhale, the more likelihood that one’s going to hit one of those receptors and cause the infection.
So you can – it’s to do with the volume of air inhaled, wherever you are in the room, and the concentration of particles in that. And obviously if you’re close up, the concentration’s likely to be greater than if you’re further away. And the volume of air inhaled, that’s the total volume, depends on how fast you’re breathing, how much you take in, but also how long you are. So we now have –
Lead 3: As in how long you are exposed?
Professor Clive Beggs: Exposed.
Lead 3: Right. Can we hive that off, if we may, and deal with that slightly later –
Professor Clive Beggs: So the volume and the concentration. The concentration changes where you are in the space, but it’s dependent also on how much air you breathe in, and that’s dependent on time.
Lead 3: Can I see if I –
Lady Hallett: Professor, can I interrupt to say, I know how careful you are trying to be and it really is very helpful information, but Ms Carey’s an expert at getting what she needs and what I’m going to need, so if you could just try to shorten your answers. And if she wants more, she’ll ask for more?
Professor Clive Beggs: I will, yes, certainly.
Lady Hallett: Because we have limited time. I’m sorry to –
Professor Clive Beggs: No, that’s okay, it’s very understandable.
Ms Carey: Thank you, my Lady.
Can I ask you, to see if I understand this correctly from your report, if the susceptible individual spends two hours in the room with an infectious person, they’re going to be at much greater risk of acquiring the infection compared to someone who’s only in there for five minutes?
Professor Clive Beggs: Yes.
Lead 3: All else being equal?
Professor Clive Beggs: All else being equal, yes.
Lead 3: But of course one has to bear in mind then how close you are to the infectious person?
Professor Clive Beggs: Yes. So you – all right?
Lead 3: Go on, you can carry on.
Professor Clive Beggs: So we could have, for example, someone who is close to a person for a short period of time inhaling a certain infectious dose. They’re got a high concentration but they’ve taken in for a short time. Or in a café, for example – or someone on the other side of the café is working there for four hours or – you know, with a computer, and they’re breathing in infectious air, they’re breathing in a smaller concentration but for longer, and so they can actually get the same infectious dose, actually a greater infectious dose, even though the concentration is lower in the far field.
Lead 3: So for the infection to occur, is this right, you need to have inhaled a respiratory aerosol that contains the virus?
Professor Clive Beggs: Yes.
Lead 3: The aerosol must come into contact with a receptor, nose, mouth?
Professor Clive Beggs: Wherever, yeah.
Lead 3: The virus in the aerosol must be fit enough to bind on to the receptor?
Professor Clive Beggs: Yes, it’s got to be viable to get in and there’s got to be enough of it to get into it, basically, yeah.
Lead 3: Then once inside the receptor or the cell, the virus must overcome any of our own immune system in order for the infection to take hold?
Professor Clive Beggs: Yes, so what actually happens is that most virus particles either miss receptors or get knocked out by the defence, the host defences, or they’re not fit enough, and it’s just that few that get through. It’s a numbers game.
Lead 3: Right. Does that generally mean, therefore, that a large number of virus particles need to be inhaled in order for an infection to be established?
Professor Clive Beggs: The figure that sticks in my head from, I think it’s the Skagit choir analysis, or is it – that’s another paper – is 600, I think, in this particular case, for a kind of ratio of 600 to 1, the expected dose to be inhaled.
Lead 3: Right.
Professor Clive Beggs: But that, again, is an estimate that I – that’s in –
Lead 3: In short, you’ve got to get a large number of –
Professor Clive Beggs: You’ve got to get a large number, but that is always the case with viruses, you know.
Lead 3: All right. If I understand your evidence correctly, therefore exposure time and concentration of the virus in the air are critical when we’re looking at how the infection gets in and spreads?
Professor Clive Beggs: Absolutely, yes, the longer you spend in a space, even if the concentration is not that high, you’re at risk.
Lead 3: Can I ask you about an example that you refer to in your report, please, at paragraph 74 on page 30 of your report, which might highlight the importance of exposure time and indeed concentration of the virus in the air.
Professor Clive Beggs: Sorry, which is it? Yes. I’ve got it, yep.
Lead 3: Yes. I think you looked there at situations where the viral load is allowed to accumulate, let’s say in a poorly ventilated room –
Professor Clive Beggs: Yes, right.
Lead 3: – even short exposure times can result in significant risk?
Professor Clive Beggs: Yes.
Lead 3: So actually – let me just finish – and this is especially in the case where individuals may be shouting, singing or just talking, and then you go on to refer to a study by Alsved. Help us with this paragraph, please?
Professor Clive Beggs: Yes, no problem. Right, so two things happen, really. When you exhale a virus – exhale aerosols which contain virus, so you imagine someone in the near field, they’re going to get a waft of this thing through their – past them.
Lead 3: In their near field, 1 to 2 metres, roughly?
Professor Clive Beggs: 1 to 2 metres, yeah, I’d call it that kind of region. They’ll get the first waft, which is a high concentration, and that could occur indoors or outdoors. But those aerosols then, assuming they’re not inhaled, progress into the room and mix, and then the air currents in the room take them and take them around, and this is where it differs from indoors and outdoors.
So outdoors there’s a progressive dilution but what happens indoors is, because we’ve got an enclosed space, these aerosols start to waft around and build up in concentration in the space. So someone in the far field, who’s some distance from the infected person, they can be breathing a kind of soup of aerosols if the virus is in there, if it’s a poorly ventilated space, of a fairly high concentration over quite a long period of time and it’s made even worse if you’re in an environment like the Skagit choir, which we may come on to later where people were singing, if it’s noisy, a nightclub or a church or something, where lots of superspreading events have occurred, where we generally have got people raising their voices: singing is a classic one.
Lead 3: Yes.
Professor Clive Beggs: So they’re producing lots of aerosols into the space and the concentration builds up and everyone’s breathing it in. In that situation, Alsved calculated quite a short period of time, even within 37 minutes. It depended on the ventilation rate and all the rest of it.
Lead 3: So is it fair to say that healthcare workers treating patients who are generally in the near field, in that 1 to 2-metre range, or potentially right up close to them, are more generally exposed to the near-field risk?
Professor Clive Beggs: In that specific situation, yes and no. They’re in the near-field risk when they’re treating that patient and caring for that patient, they’re in the far-field risk when they’re at the nurses’ station or it’s a cleaner or someone who is working around about, and other patients maybe in the near and in the far field, depending on the situation.
Lead 3: So it’s not just nurses, non-clinical staff like the cleaners, the porters, some –
Professor Clive Beggs: Non-clinical staff are also exposed to it in offices of hospitals, and things like that as well.
Lead 3: I think you said in your report – I won’t take you to it, Professor – that when considering the near field direction is important, clearly face-to-face poses more of a risk?
Professor Clive Beggs: Yeah.
Lead 3: Side to side, a risk, but not –
Professor Clive Beggs: Yeah. Near field definitely. If you’re in front of that – what we call the exhalation plume, you’re going to get a higher dose. Actually, there is a slight caveat to that in the clinical scenario, because patients are often in bed and so the thermal plume rises up from them, as their exhalation does as well, and so clinical staff are often above the patient. So I would include both the exhalation plume and the thermal plume. So if you’ve got a patient and you’re taking blood pressure or something and they’re lying down, you can be leaning over them and getting both the exhalation and the thermal plume. So, yes.
Lead 3: Understood. There is a number of variables there as to how you end up getting infected but can I look at a different form of transmission now briefly and come on to what you’ve termed “Fomite and contact transmission”. It’s at page 36 in your report, Professor. Again, terminology may be important here, so actually – thank you – the key findings may be a helpful way in to this evidence.
I think you said in your report that historically flu and other respiratory viruses have been assumed to be transmitted by droplet transmission, the larger particles, and by contact.
Professor Clive Beggs: Yes –
Lead 3: Is that right?
Professor Clive Beggs: – and fomite as a –
Lead 3: Yes.
Professor Clive Beggs: – subgroup.
Lead 3: Yes. There is direct contact, indirect contact, there is also the phrase “fomite”, so let’s deal with those, if we may please.
Can I just deal with contact. Direct contacts: help us, please, what is meant by the phrase direct contact? If it helps you, it’s paragraph 91 on page 37.
Professor Clive Beggs: Yeah, right, so I’m not actually saying contact, I’m talking about direct routes and indirect routes there, and it’s important in the thing, so shall I explain?
Lead 3: Yes, please do.
Professor Clive Beggs: I was asked by the Inquiry to examine all the routes, right, and I have done quite a bit on hand washing in my time but mostly on things like MRSA. So I wanted to set it alongside the airborne and the droplet as well, so we’re looking at the whole picture because it’s really important that the number of intermediary steps, the virus can get diluted basically, right? So I wanted to introduce, talk about direct routes, so in this report – it’s confusing because they talk about direct contact and indirect contact, so I’m talking about direct routes in this report and in this paragraph, as meaning there’s no intermediary stage. So that could be a droplet going from coughing and landing on someone’s eye or it could be an aerosol going out, flowing round and going up someone’s nose. That’s direct. There’s –
Lead 3: Pause.
Professor Clive Beggs: Yep.
Lead 3: Thank you. I just want to make sure I understand that right: the virus travels from the infected person to the receptor without touching anything in between?
Professor Clive Beggs: Yeah, so whatever is in the virus that left the mouth, and we’re talking in those situations, certainly in the short – in the near field, within, you know, seconds; in the case of the droplet, within minutes. So there’s nothing in the way to interfere.
Lead 3: Understood. Indirect may be obvious now, but help us, please, looking at paragraph 91, I think you said that indirect routes involve one or more intermediary steps.
Professor Clive Beggs: Yes, so –
Lead 3: So the context of respiratory transmission, help us with that, please.
Professor Clive Beggs: I suppose that could be with the intermediary step there is the droplet when it lands on the outside of the nose and someone touches it and then rubs their eye. That would be an intermediary step.
Lead 3: Or a droplet falls onto a bed handle on a patient’s bed –
Professor Clive Beggs: Yeah, yeah, classic. There’s a bed rail or it drops onto a surface, a patient’s surface, so the patient does that, or on to a medical instrument or something.
Lead 3: Understood.
Professor Clive Beggs: The nurse touches it and then rubs their eye, for example, or whatever.
Lead 3: So there is contamination effectively via some kind of intermediary surface –
Professor Clive Beggs: An intermediary step and the classic one is, you know, the handshake, is that.
Lead 3: Well, I wanted to ask you about that because handshaking is sometimes given as an example of direct but, if I understand you correctly, it isn’t because it’s got to go onto my hand, I shake the other person’s hand and they then have to transmit it to a receptor; is that right?
Professor Clive Beggs: Yes. In the textbooks, when they’re talking about hand contact, they say that’s the direct route. I’m doing this for this report because I’m trying to make sense for everybody that there are intermediary steps, and that’s really rather important. So the direct contact, say, touching someone’s hand or touching something, I suppose if someone kissed someone that could be a very direct route, you know, but that’s a very intimate – I don’t know where to go with that one, really. We’ll leave that at this moment.
Lead 3: Yes.
Professor Clive Beggs: I’m blushing now, I can see this here.
Lady Hallett: I don’t think kissing got banned, did it?
Professor Clive Beggs: I don’t know. What happened in the home stays in the home, I suppose, yes.
You know, but the point is it’s the idea that the classic of – the textbooks would say the classic of the indirect and – two indirect routes as I’ve classified here, with the hands. The classic one would be, “Hello”, you cough into your hand, you shake hands with someone else, they then take it and they rub their eye or their nose or something. Or with a fomite that would be you cough into your hand, you touch the door handle you walk away, someone else then touches the door handle, then they do that.
Ms Carey: So that is what is meant by fomite?
Professor Clive Beggs: That’s fomite, yes.
Lead 3: Can I take it that where you’re dealing with indirect transmission, viral material is lost through degradation?
Professor Clive Beggs: Yes, every time you touch, so let’s take the door handle, that’s a great one to do.
Lead 3: Yes.
Professor Clive Beggs: So even when you cough and you cover your hands, not all the virus went onto your hands and the hands actually aren’t very good at – porous surfaces and hands tend to kill the virus, it doesn’t last for very long. So whatever goes onto the hands, then it has to be transferred to the – it’s lost something there. It goes to the door handle, it’s lost some more.
Then the next person to touch the door handle doesn’t necessarily touch them straightaway, they might wait an hour and, in that time, it’s degraded over time. The person touches it, it loses them, and in fact I think it was Raymond Tellier did some analysis and reckoned that only about 1% of it eventually gets to the target, if it does get to the target. So it really is degraded.
So time is a very key important thing in there.
Lead 3: Now, clearly, though, when you’re talking about direct contact, it goes – you cough in my face, effectively?
Professor Clive Beggs: Very short.
Lead 3: Yes, exactly, that’s the point.
Professor Clive Beggs: So the virus is fitter, and it hasn’t been through any intermediary steps.
Lead 3: Okay, so survival time depends on the surfaces, how porous, all of the other ways in which could –
Professor Clive Beggs: Yeah, that was fully understood initially, but later on many studies have shown that the porous hands and things, it doesn’t survive that well on it. But hand washing is really good by the way, so don’t, you know …
Lead 3: Well, that actually was going to bring me onto – I think you’ve said in your report that the fomite transmission, touching the inanimate object, and indeed contact transfer plays a role but the precise proportion of that is not yet known; is that correct?
Professor Clive Beggs: Yes, in my opinion. At the beginning of the pandemic, it was thought to be much more important than later on but I’m sure clinical witnesses will tell you the same thing. As it went on, it got downplayed and – certainly the fomite and the contact – and so less emphasis was on that and more was on the droplet.
So I think it does make a contribution but I don’t think we understand how much of a contribution. But I would say it’s a significant but minor contribution. That’s my personal opinion.
Lead 3: Fine. I think you did say in your report at paragraph 105, though, and you made the point that the precise proportion of fomite and contact transmission that plays a role is not known but the IPC people – by which you mean those drafting the guidance – and public health assumed it to play a greater contribution whilst airborne, certainly initially, was considered to be an unlikely –
Professor Clive Beggs: Yeah. Well, I always like to kind of quote higher authorities than myself, right, and the PIP report, which is the Pandemic Influenza Preparedness report from 2011, there was two of them, and there you see it in 105, it’s:
“Since the role of hands in the transmission has actually never been demonstrated epidemiologically, one may hesitate to attribute great proportion to this pathway.”
The epidemiological evidence is not that strong, to be honest.
Lead 3: Perhaps before we break for lunch, I want to deal with one other topic, if I may, my Lady, and it’s to look at some of the other terminology that is used and then perhaps, after lunch, we can look at some of the historical controversy and assumptions that played out in particular in the IPC guidance.
So, Professor, can I ask you this: I think you were shown a statement by Lisa Ritchie, and it will be in your bundle behind tab 3. Now, she was the chair of the IPC cell made up of a number of individuals, and obviously it wasn’t proportionate for the Inquiry to speak to all of them.
Professor Clive Beggs: Yep.
Lead 3: So, although she is the front person, I want it to be made abundantly clear that she’s often speaking on behave of the cell’s position. Occasionally she speaks to her own position and we’ll deal with that when we hear from her, but can I just ask you about some of the terminology that she uses, whether you agree with it, and see where we end up just before our lunch break.
Could you turn, please, to page 13, and if we put it on screen, it’s INQ000421939_13. We’re, I hope, a bit more familiar now with some of the language, and there may be a divergence here, and if we look at “Droplet transmission”, there the statement sets out that:
“Droplet transmission involved droplets ([of 5 microns to about 200] in diameter) from an infected person’s respiratory tract reaching the eyes, nose or mouth of another person.”
Then it sets out:
“Large droplets [greater than 20 microns] typically fall to the [floor] within 1 metre …
“Large droplets [she says at the bottom of paragraph 43] fall to the ground within seconds, while smaller droplets [5 to 20] can stay airborne for several minutes.”
Now, just pause. You have told us about the distinction between 100 microns and now we’re introducing much smaller figures, and I want to try and understand what you say about droplet transmission firstly involving droplets of 5 microns to about 200 microns in diameter; is that a range of diameter with which you’re familiar and with which you would agree?
Professor Clive Beggs: I disagree with it, but I am familiar with it, if that makes sense. May I just elucidate one thing?
Lead 3: Yes, of course.
Professor Clive Beggs: Earlier on in your questioning, earlier on in the first session, you asked me about the 100 microns and I said there was two schools of thought, and I went down the engineering/physics, which are my – which I believe is the correct one because it’s dealing with the physics, which is well established and has been established for about 150 years, certainly 100 years, in this situation since the 1930s. The other branch is the medics and the IPC branch, and this represents that, and they – we will see it in the next session – they had this 5-micron demarcation. They didn’t actually say 200 microns but that’s a good upper limit, it’s not bad. But that 5 microns, they said anything bigger than that was a droplet.
So I am familiar, I’ve seen this many times in many things but, as far as I’m concerned, that has no basis in physics, it’s completely arbitrary, that first statement there. Certainly, they do go up to 200 microns and they certainly are in the 500 microns but they’re not droplets, those are – below 100, those are aerosols.
Lead 3: Right. So –
Professor Clive Beggs: But, you know, they can reach the eyes and –
Lead 3: Yes, that bit there is no dispute with but, from your evidence, if I understand you correctly, “droplet” is referring to microns 100 plus?
Professor Clive Beggs: Yes.
Lead 3: Aerosols lower than 100?
Professor Clive Beggs: As in that diagram, which we saw earlier on, Wang’s diagram.
Lead 3: Do we need to look at the paragraph 43 referencing large droplets greater than 20 microns now being introduced, typically falling to the ground?
Professor Clive Beggs: It’s just not true.
Lead 3: Right.
Professor Clive Beggs: It’s not true. In fact, I can tell you what a 25-micron particle, which is larger than that, right, it’s factually incorrect, that will take about one – to fall out of the air, about 1.3 minutes, from a height of a standing height, and remember that is still air not in air. That has a descending velocity, according to Stoke’s law of 2.5 centimetres per second, bear in mind that the average air velocity in this room is in the region of 15 to 25 centimetres per second, that type of order.
These particles in that one minute, they will travel much further – can potentially travel further than a metre, especially if they’re –
Lead 3: So there is a divergence here between physicists, if I put it like that –
Professor Clive Beggs: Yeah.
Lead 3: – and the clinicians and I want to try to understand why is it important in terms of infection prevention and control measures?
Professor Clive Beggs: Well, if you feel that a particle, so say most particles are in that kind of smaller range, if you feel that – but above 5 microns, if you think that that’s a droplet and doesn’t go more than 1 metre, which is the classic viewpoint, I’m not saying that’s here necessarily said quite like this, but the classic textbook says that a particle greater than 5 microns doesn’t go more than a metre, then, if you stand 1.5/2 metres away, socially distanced, you think, well, all the droplets will fall on the floor and you’re not taking into account that the aerosol will be inhaled, especially both in the near field and in the far field.
So you’re completely – you don’t think the aerosols are important, basically, especially if you don’t believe that the virus is in them, which we now know the virus is in those things.
Also, I should say, you would be recommending a surgical mask –
Lead 3: Right.
Professor Clive Beggs: – because you would be trying to stop droplets and not being too concerned about the aerosols, if that was the case.
Lead 3: So I understand this correctly, the size of the droplet can determine not only how far – sorry, the size of the particle can determine not only how far it can go but the type of IPC measure that might be required by the healthcare worker in terms of masks and other bits of PPE they might need to wear to help protect them?
Professor Clive Beggs: Yes.
Lead 3: All right, okay.
If we briefly turn to the next page in the statement and just deal with airborne, and there set out is, for the purposes of Ms Ritchie’s statement, what she says about airborne transmission:
“… involves infectious particles … in a respirable size range that can remain suspended in the air for long periods and be dispersed by air currents over distances greater than 1 metre.”
Professor Clive Beggs: Right, can I just say –
Lead 3: Yes.
Professor Clive Beggs: – to clarify, a respirable size actually has a strict definition in the –
Lead 3: Right.
Professor Clive Beggs: Well, it’s interpreted as less than 5 microns generally, right, that’s the demarcation.
Lead 3: Thank you.
Professor Clive Beggs: Certainly in the PIP report, that’s there. It’s the demarcation between the particles that go deeper into the lungs and stay higher up, so 5 microns is generally – it’s not stated here but that would be the kind of size there.
Lead 3: Right.
Professor Clive Beggs: So, sorry.
Lead 3: It’s all right.
Professor Clive Beggs: Are we –
Lead 3: So, I’m sorry, I lost my train of thought there:
“Airborne transmission involves infectious particles … in the respirable size range that can remain suspended in the air for long periods and be dispersed by air currents over distances greater …”
Do you agree with that summary in that paragraph?
(Pause)
Lead 3: Put another way, do you think it accurately reflects?
Professor Clive Beggs: Yeah, no, I agree with it but I would say that particles over 5 microns can also do that as well and go further than –
Lead 3: Fine. Now, she refers in the statement to short range transmission and long range. You’ve told us about near field and far field. So, again, the terminology not necessarily being on all fours. Set out here is:
“Short-range aerosol transmission involves tiny respiratory droplets (less than [10 microns]) that can spread over short distances (less than 2 metres).”
Do you agree with that?
Professor Clive Beggs: I disagree with that.
Lead 3: Why?
Professor Clive Beggs: Right. Because particle – a 10-micron particle in still air will take 8 minutes to drop 2 metres, right, to fall out of the air. Sorry, 8 metres – minutes, I should have said. So 8 minutes, that’s in still air, it can move a lot further.
So a 10-micron particle – so particles that are less than 10 microns are going to obviously travel short distances but they’ll travel a lot further than the short distances. So I think this says “can spread over short distance less than that”, the implication being there that it can only travel over less than short distances. No, it can’t, it can travel over short distances and long distances. In fact, that’s been known about for years. I’m sorry, you know, back in Wells’ work in the 1930s on TB they were talking about that going …
Lead 3: Long-range transmission, I suspect you’ve just dealt with, and there is set out at paragraph 49, it’s her view that the distinction between a respiratory aerosol and a droplet in terms of size is:
“… an academic consideration that cannot usefully be applied in national guidance.”
Now, can I make it clear this is not a them and us?
Professor Clive Beggs: No, I know.
Lead 3: There is a genuine divergence here between the physicists and perhaps the clinicians, so please don’t misunderstand –
Professor Clive Beggs: Yeah.
Lead 3: – the position but I just want you to help us with your view about some of these terms and indeed some of the IPC measures that might flow from the terminology.
Professor Clive Beggs: Right. Yeah, I will. I’m not trying to do a them and us at all, you know, I’m really trying to help here. I’m smiling because it highlights the difference of opinions, right?
Lead 3: Exactly.
Professor Clive Beggs: Right, so I want to say straight up: I work with clinicians but I am not a clinician, you know that, but I have utter respect for clinicians and I see how they deal with patients all the time. So from an infection prevention and control background, which this person is talking from, they’re having to deal with a whole load of practical things. My answer to this is it’s not an academic –
Lead 3: Why?
Professor Clive Beggs: Because it’s really important to understand how infection is transmitted, how viruses are transmitted because, if you want to develop interventions you need to know how it’s transmitted and you need to know kind of the relative importance of various routes, and then you can decide, develop optimum strategies to minimise that, to mitigate that, and sometimes you might say, you know, we don’t have to measure the particles, you know, we don’t have to measure the sizes or, you know, the things that are put down here. What we need to do is understand it, then we can take measures that help to mitigate transmission, that’s why it’s important to understand, so I don’t believe it is an academic issue.
Ms Carey: My Lady, may we pause there?
I referred to her as “Ms Ritchie”; she is Dr Ritchie. I meant no disrespect, I’m sorry about that.
But would that be a convenient moment?
Lady Hallett: Of course. 1.55.
Ms Carey: Thank you.
(12.54 pm)
(The short adjournment)
(1.55 pm)
Lady Hallett: Ms Carey.
Ms Carey: Thank you.
Professor, we’ve got a number of topics to deal with this afternoon, and can I just try and deal with your evidence in relation to the historical controversy. I suspect we’ve got a flavour of it already from the evidence that you’ve already given, but where things have gone wrong or have been assumed to be the position, what I really want to understand is what impact that had on IPC guidance and IPC measures.
So can I just deal with the first and perhaps one of the main areas of controversy, which is that Covid was not airborne. Now, I gather from all the evidence that you’ve given that you disagree with that –
Professor Clive Beggs: Yes.
Lead 3: – and indeed believed at the outset that it was airborne, and indeed now in 2024 have firmed up that belief?
Professor Clive Beggs: Absolutely.
Lead 3: All right. The World Health Organisation’s position requires just a moment’s examination. In March 2020, is it right that the WHO, World Health Organisation, position on transmission of Covid was that it was not airborne?
Professor Clive Beggs: Absolutely, they even Tweeted about it.
Lead 3: Right. By April 2021 there was partial acceptance by the WHO that Covid was airborne?
Professor Clive Beggs: Yes.
Lead 3: And it was December 2021 that they stated that Covid-19 could be transmitted via aerosols?
Professor Clive Beggs: Yes.
Lead 3: Right. Your position is, if I may summarise it, that by September 2020 – and if it helps you I’m at a paragraph 139 in your report on page 53.
Professor Clive Beggs: Yep.
Lead 3: Thank you. It’s helpfully highlighted there. You consider that:
“… the weight of the evidence presented …”
You set that out in your report and I won’t take you through it:
“… indicates that by the end of September 2020 there was enough moderate certainty evidence to strongly suggest that [SARS or Covid] could be transmitted via the airborne route …”
Pause there. The reference in there to “enough moderate certainty”, is that your terminology?
Professor Clive Beggs: Yes, it is my terminology. I’m referring to – I’m kind of trying to look at it in the whole. I was convinced it was airborne but, if you’re looking for – there’s a range of evidence from a lot of different angles, which we may go into, I don’t know, but I was pretty – I was – felt that it was a good certainty, moderate certainty, there’s not beyond absolute doubt but it was definitely a strong possibility. That’s the kind of thing that I’m –
Lead 3: All right, that’s what you were trying to convey there?
Professor Clive Beggs: That’s what I’m trying to convey there. You know, I was convinced and many of my colleagues from my background will be utterly convinced that it was, by that time.
Lead 3: Can I summarise it this way: you thought there were a number of sources that pointed, by September 2020, to it being airborne?
Professor Clive Beggs: Yes, yes.
Lead 3: All right. That was obviously 15 months or so before the WHO, in December 2021 –
Professor Clive Beggs: Yes.
Lead 3: – stated that it was transmitted via aerosols?
Professor Clive Beggs: Yes. Yes.
Lead 3: Now, we have alluded this morning to the fact that there has been a shift in the scientific consensus from the position in 2020 by those writing the guidance, those advisers and the like, to where we are in 2024. Do I understand it correctly that you consider that that shift in consensus was largely driven by scientists?
Professor Clive Beggs: Yes.
Lead 3: Okay. In your report, if you could just take down the insert –
Lady Hallett: Sorry to interrupt. You’re distinguishing between clinicians and your kind of scientist or are you saying virologists?
Professor Clive Beggs: It was driven by people from a multidisciplinary background, predominantly very much influenced by people from physics, people like Lidia Morawska, Cath Noakes, engineers, myself and others, but there were clinicians involved in that. There was a letter of I think about 230-odd eminent scientists/clinicians to the WHO saying, “Look, it’s airborne”, and I can’t remember the date, I’d have to look at –
Lady Hallett: So it was across the board?
Professor Clive Beggs: Yeah.
Ms Carey: Thank you very much.
Professor Clive Beggs: But they were absolutely influential in that.
Lead 3: Underpinning that evolution from the position at the start of the pandemic to at the end were obviously a number of scientific papers, and you’ve set them out in your report, and I’m not going to go through them all, save for one that you considered to be of some import in moving the shift towards people accepting airborne transmission.
Can I ask you, please, about paragraph 132 in your report, and if we’d like to put it on the screen, there is a summary of it on page 55, and it’s the Skagit Valley superspreading event, and on the screen it’s the entry of 26 September 2020.
Professor Clive Beggs: Yeah.
Lead 3: Just, in a nutshell, tell us what happened at the Skagit Valley superspreading event and then why you consider it to be so important?
Professor Clive Beggs: Right. I just want to set it in context, if it’s all right, just very briefly.
Lead 3: Briefly, thank you.
Professor Clive Beggs: Prior to that, right from March, there was evidence that – of people sampling the air in hospitals and finding RNAs, so that was around. There was evidence from lab work that the virus could stay viable in the air for long periods of time, this is all evidence leading up to that, people have cultured live virus from the air, and people realised that this was in the aerosols and everything. This led up – so the evidence was building, that’s what I’m saying, that’s why this is all part of the same picture, and this was the kind of icing on the cake.
This was when – it’s a horrendous event which some of you may know of, which was a choir had a practice in the Skagit Valley Chorale and 61 people were in this practice, and I forget how many hours it was but it was a number of hours, and I think in a fairly large building as well, a large space, and so they weren’t all in close contact with each other, they weren’t necessarily socially distanced or anything, as far as I can remember.
And 53 of those people became infected, 53 of 61 became infected and, unfortunately, two people died and this was reported – first reported, I think, probably in August but not – the analysis was done with something called the Wells-Riley equation and looking at the whole route of transmission and the authors came to the absolute conclusion this could not have been by hand contact or droplets; it was far field aerosol transmission, and that really was epidemiological evidence that confirmed what we had suspected from all the other studies that were coming through.
Lead 3: Fine, and they set out in that little –
Professor Clive Beggs: So that’s why that was a key thing.
Lead 3: Thank you. I think, in addition to concluding there was overwhelming evidence of long-range or far-field airborne transmission, it perhaps matters not for these purposes, that fomite or ballistic droplet transmission was unlikely to explain a substantial fraction of those 53 cases?
Professor Clive Beggs: Absolutely.
Lead 3: All right, and you’d, in your report, said that this study or event gave wider traction to the notion that Covid might be airborne?
Professor Clive Beggs: Yes, those of us who were working behind the scenes to try to understand this, and were convinced it was airborne, we were – this was really helpful, because this was further evidence to that. But also people were starting to take notice, and that’s when it gained traction further afield because of that.
Lead 3: To help root this in the pandemic, this is now probably just before the second wave, my Lady, and we’re around September 2020, going into the second wave later that year.
Now, we just briefly touched on the WHO position. I want to ask you about the position in the UK, and I think you say at paragraph 140 in your report that Professor Noakes – who my Lady heard from I think in Module 2 – certainly was aware that, from 14 April, transmission of Covid might be occurring through the airborne route, and she then went on to form the Environmental Modelling Group, and that group, as my Lady knows, produced a number of documents in 2020 and into 2021, which showed the change from Covid-19 is not airborne to Covid-19 is airborne. Is that, generally speaking, correct?
Professor Clive Beggs: Yes, that’s what I’m saying here. I’m using the Covid is not airborne to Covid is airborne as a vehicle to try and convey the change of consensus.
Lady Hallett: Just before you move on, you said the Skagit Valley Chorale was September 2020, second wave. When I Googled it I thought it was March 2020.
Professor Clive Beggs: Ah, right.
Ms Carey: Can you help?
Professor Clive Beggs: Yes, I can clarify. The first outbreak was reported in Emerging Infectious Diseases, which is a CDC publication and it reported the outbreak but didn’t do the analysis.
Lady Hallett: Oh, I see, so this –
Professor Clive Beggs: But then the group, it didn’t mention airborne, so group came together with Professor Noakes, Shelly Miller –
Lady Hallett: It’s all right, I don’t need to go into more detail. So the event took place in March, analysis later?
Professor Clive Beggs: They did the analysis – the epidemiological analysis and this is showing that that could not have been – highly unlikely it would have been by that route.
Ms Carey: Thank you for that.
Professor Clive Beggs: That took several months, obviously.
Lady Hallett: Thank you.
Ms Carey: I think I should add that, although the Environmental Modelling Group shifted its position from Covid-19 isn’t airborne to is, again, I think you set out in your report at paragraph 143, not all scientists agree with that shift. I won’t go into that but it’s just to allude to the fact that there isn’t always consensus about this.
Professor Clive Beggs: It was gradual, it was in steps.
Lead 3: I suppose, really, the question comes down to this: can you help us as to why you think it was assumed at the start of the pandemic that Covid was not airborne? Your paragraph 125 might help you, Professor. It’s at page 49 in your report.
Professor Clive Beggs: 125?
Lead 3: Yes. Essentially, why was it assumed at the beginning that Covid wasn’t airborne?
Professor Clive Beggs: Quite simply, it was assumed it was droplet borne, was the main route. Droplet borne, don’t travel, the large droplets is where it was assumed, in my opinion, wrongly, as it’s transpired, that most of the virus was in the large droplets and these do not travel more than about 1 metre, 1.5, therefore the only people who can get infected are the people who are in close range, therefore it is droplet borne. So where the virus is in the particles is hugely important because it – everything – it’s kind of house of cards, everything rests on that.
Lady Hallett: Was there any basis for that assumption? Why would you not work on the basis that we don’t yet know the route of transmission –
Professor Clive Beggs: That’s an excellent answer – sorry, an excellent question. It’s an a priori position. So when you look at trying to – this is what people don’t realise. When you’re trying to interpret epidemiological data of outbreaks, and indeed animal experiments, you canvass it with an a priori position, you say: does it fit with this or what we expect? The problem there is that the – when you actually drill down into the evidence, and it’s going back to the ’40s, and things like this, that you can’t tell whether the near-field transmission is by droplets or aerosols. It could be either, from the epidemiological and the animal study data.
But because you take the a priori position, which seemed reasonable at the time, that most of the virus is going to be in the largest droplets, therefore that would explain that these results would be – it’s plausible it’s in the large droplets.
In the fine aerosols there’s – after all there’s hardly any virus, at that time, and the PIP report says that in 2011. That’s the justification for the whole thing, they actually set that out quite clearly. Because they assume it’s in the large ones, therefore all the epidemiological evidence and all the animal studies are interpreted as being droplet borne, then people come along afterwards, they report it, yes, it’s been shown that it’s droplet borne, but it was all on this assumption.
If you flip the assumption, if you knew that they were in the smaller particles you’d say, “Well, it was all airborne” and suddenly all the evidence would show it was airborne. So it’s an a priori assumption that was reasonable at the time that in the last 10, 12 years has been challenged. But whether people are aware of that –
Lady Hallett: Well, that’s what I’m questioning. Is it reasonable, if you don’t know the route of transmission, surely you should be preparing for and guarding against – I think some core participants have called it the precautionary principle, though I’m wary of that because I’ve heard it has different meanings to different people, but surely you should guarding against every possible route of transmission until you know?
Professor Clive Beggs: You’re absolutely correct. I – sorry, another of my hats is doing statistics and I spent a lot of time looking at that, and one of the problems with stats is, generally, medical statistics we’re trying to eliminate what’s called a type 1 error, which is we’re trying to say something is – we want absolute proof to show that that drug makes a difference, and we’re not so worried about when we get it wrong on the other side, the type 2 error, when we say – basically, which is with the pandemic, it’s not airborne and it is airborne, we’re not too worried about that generally. But in a pandemic that’s exactly what you don’t want, you want to be precautionary.
So one of the problems was I think there was a mindset there that followed through – sorry, I’m waxing on a bit too much there –
Lady Hallett: Sorry, it was my fault, I interrupted.
Ms Carey: Not at all, because in fact that’s where I was going to get to, because if in reality there is no clear evidence at the beginning of a pandemic about what route of transmission is adopted, do you think it would be wise for recommendations to cover all modes until you know more?
Professor Clive Beggs: I certainly would do, and this is one of the big complaints that myself and others have is that people have a kind of confirmation bias, in the sense that they confirmed what they thought and they read that into it.
And I’m not saying that there isn’t droplet transmission, but to rule it out when – just take the simple fact that you always have aerosols with droplets. That’s been known about for many, many years. If you’re going to be precautionary, what you see in many of the randomised controlled trials are people are going to a very high bar of proof to jump over, when in fact, as we’ve seen, there’s very little evidence for the hand-borne route, and then they don’t apply that high bar of proof for that because that’s the a priori received position, it’s in the textbooks and that. So that’s one of the weaknesses I see of the whole thing.
Lead 3: Thank you.
Can I deal with one other or two other matters in this vein. I think you say at your paragraph 150 that there was an important shift in the thinking concerning vocalisation, ie speaking, shouting, singing. I just want to ask you about that.
I think you are of the view that breathing and talking was overlooked as a way of producing aerosols; is that right?
Professor Clive Beggs: Yes. And I’d include singing as well, and shouting.
If you think about it, all the emphasis, certainly at the beginning of the pandemic, was on symptomatic situations, so coughing and sneezes. You know, people can see people are infectious: distance yourselves, cover your mouth, wash your hands, all the rest of it. But nobody was talking about just being next to someone who was breathing.
You know, think about a patient in bed, and if you think about presymptomatic patients, say in that six-bedded bay, an open bay, the other patients are with them, next to them, all day long. If that person is infectious, just talking and breathing, they may not be showing any symptoms but they still could be spreading the virus. So it’s a hugely important issue.
Lead 3: One other allied topic is that of aerosol-generating procedures (AGPs). Can I summarise your position. If I’ve got it wrong, please let me know –
Professor Clive Beggs: Yes.
Lead 3: – but do you consider that the physical science suggests that many so-called AGPs actually produce fewer aerosols than normal activities such as coughing?
Professor Clive Beggs: Yes.
Lead 3: That’s not to say that some AGPs don’t produce a lot of aerosols but there are some on there that actually produce fewer?
Professor Clive Beggs: I always – I’ve got to be a bit careful not being a clinician, so I – but from the evidence that I have seen, and there has been quite, quite serious studies and meta-analysis done, quite a lot of the AGPs which were thought to produce a lot of aerosols don’t produce that many aerosols.
Lady Hallett: AGP again?
Ms Carey: Aerosol-generating –
Professor Clive Beggs: Aerosol-generating – it’s a medical procedure, so bronchoscopy, for example, would be one, where you stick an endoscope down –
Lead 3: Now, I should add there is not always consensus about what should or shouldn’t be on the AGP list. But in general terms is this the position: there may appear to be an overconcentration on AGPs and the role they play to the detriment of us just talking and breathing?
Professor Clive Beggs: Yeah. I’ll add – if I can add –
Lead 3: Yes, of course.
Professor Clive Beggs: Yes, and in my opinion, yes, when you look at the IPC guidelines, the national IPC manual, there’s lots and lots on aerosol-generating procedures and nothing on just aerosols produced – natural aerosols produced through exhalation, including coughing actually and including that – unless it’s classified as an airborne disease. And the only thing that’s classified as that are measles and TB – are the two, yes, basically.
Lead 3: Just finally on dealing with assumptions, can I ask, please, that we put up page 45 of Professor Beggs’ report and I hope maybe segue into the Pandemic Influenza Preparedness (PIP) 2011 report.
Professor Beggs sets out fully in his report the impact of that, but I just want to look at the two finite bullet points to bring it together.
You consider that:
“The 2011 Pandemic Influenza Preparedness (PIP) report was well-conducted and correctly identified the significant remaining uncertainty about [flu].”
But it has:
“… several problems. Unlike many other studies it did acknowledge the risk of airborne transmission, but only at close range …”
Does that mean in the near field?
Professor Clive Beggs: Yes, yes yeah.
Lead 3: “… and made an important flawed assumption about large droplets conferring most of the infection …”
Whereas you are telling us in fact it is the aerosols?
Professor Clive Beggs: Yes, that’s the – that’s that fundamental assumption, and if I may just take a minute – I like this report. I was really pleased that, when I read it, they’d gone into depth, they’d justified why things were there, they’d gone through things and they were looking at it. But they made the assumption that the – which was definitely prevalent, the first study actually found influenza virus in small aerosols, less than 5 microns in size, only occurred in 2010, and they spotted that as well, but they made this assumption that most of the virus was in the large droplets and therefore very little would be in the aerosols. Therefore aerosol transmission probably wasn’t occurring, certainly not in the long range, possibly however it might be occurring in the short range, in the near field. That was their assumption. But they did say that the droplet was the main route.
Lead 3: Thank you.
Professor Clive Beggs: There is another flawed assumption but I think we’re dealing with that one in the next – is it in the next one?
Lead 3: I hope so. Can we look at the final bullet point please.
Professor Clive Beggs: If not, I will then –
Lead 3: All right. The reason it’s important, my Lady, is because the PIP report, many of the findings and assumptions in that then underpinned various guidelines for use during a flu pandemic and, by extension therefore, other respiratory virus pandemics. And it restricted respirators to only staff conducting AGPs on flu patients. And you say there:
“Newer evidence that large amounts of virus could be naturally exhaled by infectious patients did not shift this initial policy choice during the Covid-19 pandemic.”
Professor Clive Beggs: Right. Before I do that –
Lead 3: Yes.
Professor Clive Beggs: – I don’t want to forget the other point, which is not here but it’s in the text.
The other flaw in the PIP report was that they assumed that once aerosols as they went out they fanned out and you got less and less concentration. That’s what happens outdoors. But indoors, because they’re confined, the concentration over time will build up, and so people in the far field, even though the concentration will become more and they can breathe that in, that was just completely missed in the PIP report.
So those two assumptions I felt were flaws in that report.
Going back to this here, they had raised – what I did like was they raised the possibility that short-range aerosol transmission was occurring for the first time, which I thought was good, but they were mainly concerned about aerosol-generating procedures, as you say, and this is why it influenced future IPC guidance.
Lead 3: Understood.
Professor Clive Beggs: So it was influential. But there was no – again, there was no epidemiological evidence so far as I could see relating to the aerosols in the aerosol-generating procedures. I may be wrong, but I can’t –
Lead 3: That’s your position, all right. I can take that down.
And let me just deal with this. I’ve obviously asked you a number of questions and given examples relating to hospital bays and nurses attending to patients in that context, non-clinical staff going in and cleaning and the like. Can I ask you, what implications does the significance of aerosol transmission have for IPC in smaller settings, clinics, pharmacies, GPs? Is there any difference if we’re looking at a smaller setting?
Professor Clive Beggs: Right. No, the physics is the same, but – it’s exactly the same principles. Basically the aerosols will build up in a space that’s poorly ventilated. So in a smaller setting, you might be looking at a hospital – a doctor’s waiting room, you might have quite a tight, confined space with – maybe not well ventilated – with a lot of people there. You may also find that the same things apply: the longer you spend in the presence of someone who’s infected and the closer you are to them, you’re probably going to get a higher load of aerosols.
Lead 3: So across the healthcare settings it’s important to get right at the outset, or at least not get wrong at the outset, the mode of transmission?
Professor Clive Beggs: Yeah, physics doesn’t change whether you’re in a big hospital or a little clinic.
Lead 3: Can I move topic completely to face masks, respirators and, to the extent we need to, visors.
Now, Professor, we’ve already seen an example of an FRSM, and if we want one there is in your report. And I think perhaps if we could call up page 73 and a very helpful diagram there.
In short, FRSMs protect against droplets; is that right?
Professor Clive Beggs: Yeah, well, it’s fluid-resistant surgical masks, right –
Lead 3: But they can’t prevent inhalation of aerosols due to their loose fitting –
Professor Clive Beggs: Yeah, they’re loose-fitting masks around the face. They protect the wearer – well, the first and foremost thing is to actually protect other people by stopping big droplets being exhaled out, so they hit the mask inside and they don’t get transmitted to other people. But the aerosols can escape, as you can see in figure 14 –
Lead 3: We’re going on come on to that.
Professor Clive Beggs: Oh, we’re going to –
Lead 3: Yeah.
Professor Clive Beggs: They escape, but they protect the wearer in so much that large droplets heading for the nose or the mouth, but not the eyes, don’t hit that. But aerosols can get round the gaps basically.
Lead 3: And if we look at our figure 14, the first column, (a) and (d) represents the thermal exhalation plumes produced by someone when no mask is worn and they are sitting quietly – sorry, (a) is no mask is worn and (d) is when the mask is worn. So that’s what it looks like if someone is sitting quietly, the plume that is produced.
Professor Clive Beggs: So you can see the thermal plume rising up over them in every case and you can see – I presume here this person’s breathing through their nose and you can see the plume coming down, the exhalation plume from the nose going down towards the ground, not even going forward.
The next one, (b), is where they’re actually saying “also”, and the last one is a laugh actually. And then the same thing repeated with the surgical mask on it.
Lead 3: My Lady, that may be neat way of encapsulating the role a surgical mask can play in helping either prevent the spread of infection or, in the large droplet case, the inhalation of it.
Did you want to say something?
Professor Clive Beggs: Yes, can you see how, when the mask is worn, there is aerosols escaping out through – around the nose bridge, and you can see how they join into the thermal plume there and then travel wherever, in that sense.
Lead 3: Respirator masks, as we know, are tight fitting and are therefore designed to protect the wearer from inhaling aerosols?
Professor Clive Beggs: They also protect them from pushing them out into the environment as well, but they are designed primarily to protect against all particles, aerosols and droplets.
Lead 3: My Lady has already heard that in the UK we use FFP3 generally and you have to be fit tested.
Professor Clive Beggs: They’ve got head straps that go round the back of the head. That’s important because that enables the tight fit to occur.
Lead 3: If a wearer fails a fit test for whatever reason, I think you also say in your report at paragraph 197 – but you don’t need to call it up – there are respirator hoods that can be used in those circumstances if the fit test fails for whatever reason?
Professor Clive Beggs: Yes, yeah.
Lead 3: All right, now I would like to ask about the effectiveness of different mask types. And if it helps you, we go to I think around 210, or page 79, in your report.
(Pause)
Lead 3: I think you say – can we take down paragraph 210 for a moment. Thank you.
But in short, is it difficult to evaluate the effectiveness of mask types?
Professor Clive Beggs: No. It depends how you want to evaluate them.
Lead 3: Let me deal with some of the detail –
Professor Clive Beggs: Lab or field trial.
Lead 3: All right, let me deal with some of the detail then.
I think you said at your paragraph 210:
“… demonstrating that masks are actually effective at inhibiting the transmission of [Covid] has proven to be … somewhat challenging …”
Professor Clive Beggs: Yep, right, I think I just need to clarify this, because your question –
Lead 3: Clarify away.
Professor Clive Beggs: Right. So you can get a mask, put it on a mannequin or in a lab in a controlled situation and you can test the effectiveness. So it’s not difficult to do that. So that was my answer to your question. Right?
If you want to see how they behave in the real world, do they actually stop a pandemic or stop something, you have to do a trial of some nature. And that is tricky because what happens is things change, you get lack of compliance, you get different rates of infection occurring. If you want to do a randomised controlled trial – you can’t do a randomised controlled trial because every – you can’t blind it, for a start, because people know who is wearing the mask. There is a lot of factors. People get vaccinated in the middle of the thing. It get very difficult to do that type of thing.
So it’s challenging. That is challenging, the real world thing. The stuff about actually seeing how they behave in the lab, the actual physics of it, is relatively straightforward actually.
Lead 3: It was my fault, it was a bad question, sorry, for thank you for making that clear.
There is, however, as you set out in your report at paragraphs 213 and 214 onwards, findings of a Royal Society review which conducted, I think, a review of, was it, 34 different studies?
Professor Clive Beggs: Yes, it was, up to Omicron, I think.
Lead 3: Yes. I just want to summarise those because they’re important.
Professor Clive Beggs: Yeah.
Lead 3: I think that the Royal Society found that the vast majority of studies they looked at found that masks reduced infection; is that right?
Professor Clive Beggs: Yes, they were effective in mitigating and reducing the transmission of infection.
Lead 3: That wearing a mask reduced Covid transmission in the community?
Professor Clive Beggs: Yes.
Lead 3: And that seven of the studies found that respirators were more effective than fluid-resistant surgical masks?
Professor Clive Beggs: Yes.
Lead 3: And that drawing all of the different studies together, the Royal Society found – and perhaps we could highlight paragraph 215, please – there in bold, the Royal Society expert group concluded that:
“… the weight of evidence from all of the studies suggests that wearing masks, wearing higher quality masks (respirators), and mask mandates generally reduced the transmission of SARS-CoV-2 [Covid] infection.”
Professor Clive Beggs: Yeah, I mean, in blunt terms they found, looking at the overall, the whole thing – and remember, stuff that – this was done late on, after the pandemic. It’s much higher quality evidence than early in the pandemic. They found the weight of evidence was that wearing masks was better than not wearing masks, and respirators were better than surgical masks.
It’s as simple as that, really.
Lead 3: They went on to consider the specific issue of respirators and surgical masks.
And can I call up paragraph 218, please, on page 83.
We can see there the Royal Society review stated:
“There is also evidence, mainly from studies in healthcare settings, that higher-quality ‘respirator’ masks … were more effective than surgical-type masks.”
Professor Clive Beggs: Yeah, absolutely. There the N95 is an American classification, but it’s equivalent to a FFP2 actually.
Lead 3: Which is not generally used in the UK –
Professor Clive Beggs: Not generally used, but good, a very good mask, a very good mask/respirator, as we’ll … yeah.
Lead 3: So, translating that to healthcare settings, I think you said a little lower down in your paragraph 218 that there was good grounds for believing that respirators generally performed better than surgical masks at protecting healthcare workers against Covid?
Professor Clive Beggs: Yes, yes.
Lead 3: In the similar vein, going on, please, in your report to paragraph 221, a number of other studies that you cite in that paragraph, but you say there in bold – are we talking here about a distinction between FFP2 and FFP3 masks? I think we are, so let me deal with FFP2.
Professor Clive Beggs: Let me just have a quick look at this statement and see what it said.
(Pause)
Professor Clive Beggs: Yeah. Yeah.
Lead 3: Right. FFP3 is what is recommended in the UK, although my Lady will hear in due course that, in the absence of FFP3, because supplies ran out, FFP2 was considered to be an acceptable mask in the absence of FFP3.
Professor Clive Beggs: Yeah.
Lead 3: Right, and so that provides some context. Help us, please, with your paragraph 221, though.
Professor Clive Beggs: Yes. Right, so what I’m saying there is that – right, that first part of that paragraph really should be read in conjunction with paragraph 219. Could I show that, please?
Lead 3: Yes, or just summarise it for us.
Professor Clive Beggs: Right, so simply you can’t distinguish between – you can’t disentangle masks, face masks, from ventilation. The two are related and in the hierarchy of controls, right, and 219 is building the case, so here it is here.
So, basically, if you, basically surgical masks perform better when there’s lower levels of pathogens in the air, lower levels of virus in the air. So let me just give you two examples, right. If we had a room with no virus in the air and we had people wearing surgical masks and people wearing respirators, two groups, you would find no difference between them because there’s no threat. Right.
You go to the opposite end, where you’ve got loads of virus in the air, you would find that there was a huge difference, the respirators would be really effective because – if they’re fitting well and – but the surgical masks would be ineffective because there is a big supervirus out there and they’re allowing aerosols to get through. So the effectiveness of surgical masks depends on the viral load, whereas the respirators are kind of immune to that. Right?
So you’ve got to look at the load in conjunction with that. So when we come on to 221 now, right, when you’re asking me about that, if I could just have it larger, please.
Lead 3: Yes, thank you.
Professor Clive Beggs: That statement where it says:
“This led Cheng … to conclude that … surgical masks might provide sufficient protection when exposure levels are low, in virus-rich environments, such as on Covid wards, they may not be adequate.”
Right? So, in other words, if you’ve got a situation where you’ve got a whole load of Covid patients or suspected Covid patients, who are maybe even presymptomatic or at early stages and highly infectious, gathered together, you’re likely to have a high viral load in the air. Your surgical masks may not be effective against that, whereas, if you’re dealing with a Covid patient who’s maybe just one patient or a low number, and they’re towards the end of their infection and they’re not producing as much, the virus in the environment might be less, therefore the surgical mask may be more effective in that situation.
Lead 3: So pausing there –
Professor Clive Beggs: That’s what that –
Lead 3: I know, so pausing there, in a situation where there is someone dealing with a ward full of either suspected or actually confirmed Covid patients, is that an argument for saying that, where there’s likely to be such a high viral load, there is a stronger argument for the use of respirators?
Professor Clive Beggs: Yes, or better quality masks of some nature but certainly respirators would be a strong argument.
Lead 3: Right.
Professor Clive Beggs: In fact, that’s what the bold bit at the bottom is there –
Lead 3: Yes.
Professor Clive Beggs: – which was Ferris’ study found that healthcare workers who were wearing a surgical mask had a 31-fold increased risk of acquiring a ward-based infection – SARS-CoV-2 infection – when working on a Covid ward, compared to when working on a non-Covid ward. I think I’ve got that paraphrased right.
Lady Hallett: Professor Beggs, as a layperson, the conclusion seems to be like common sense.
Professor Clive Beggs: It is common sense, sorry, even to a professor of engineering, it is common sense as well.
Ms Carey: If you’ve got loads of it in the room, you need better protection than when you have less of it.
Lady Hallett: Yes, yes.
Ms Carey: Is that –
Professor Clive Beggs: Yeah, yeah, yeah. But the problem – but it’s even the hierarchy of controls. You’d be amazed that people don’t realise that they – that’s one of the challenges when you’re doing a trial, you know, how do you know the threat’s there in the first place, you’re comparing two groups who are wearing masks. One might be in a group – you don’t think about this – one might be working on a place where there’s a real high Covid risk and the others aren’t. It doesn’t make a difference, you know, do you see what I mean, this is why it’s –
Lead 3: So let me draw some of –
Professor Clive Beggs: Sorry, I’m –
Lead 3: No, not at all. Let me see if I can draw some of these threads together though because I think you make the point, and others will doubtless make it, my Lady, later in the hearing, that the realities of wearing FFP3 can’t be ignored here, they are uncomfortable, they can lead to skin irritation, they are hot?
Professor Clive Beggs: Yeah.
Lead 3: After, I suspect, this afternoon’s break, I’m going to ask you a little bit about FFP2 but let’s just pause there because you mentioned in that answer that we can’t ignore the role of ventilation, and I’d like to just come on to look a little bit of that.
Clearly though when one is talking about masks, it requires compliance by the wearer, and I think you said that you’re aware that in hospitals infected patients were significant drivers of infection amongst healthcare workers and other patients, and that mask wearing amongst patients, and I’m at your paragraph 206 –
Professor Clive Beggs: Sorry, was that –
Lead 3: 206, which is on page, if it helps you, 78.
Professor Clive Beggs: Yep.
Lead 3: “… mask wearing amongst [patients] was essential to reduce patient-to-patient and patient-to-[healthcare worker] transmission …”
But, of course, it’s difficult to enforce, particularly, for example, if the patient is so unwell they can’t tolerate wearing a mask.
Professor Clive Beggs: Can I just explain that a bit more in its full entirety, as briefly as possible?
So what was found in the – various studies have found is that the most – most of the infection to other patients was from patients who became infected with Covid in hospital, nosocomially infected patients in hospital and they infected other patients and they also infected healthcare workers, right, they drove it, and the reason they did that is because they caught the infection in hospital and they were there during that incubation period and early infectious periods. That’s when they were most infectious, so anyone who came into contact with them was going to be at risk. So they’re the kind of key players in terms of driving infection in many situations.
So one of the things that my colleague Chris Illingworth and his study at Addenbrooke’s was – found from his study was to encourage patients to – in-patients to wear masks. Now, this is a big problem because these patients are ill, they’re uncomfortable and they’re certainly not talking about – we’re talking about surgical masks not respirators or anything – and they’re trying to get in-patients to I think – according to my clinical colleagues at Addenbrooke’s, they were trying to do that but they kind of ended up all over the place and it was difficult, you know; people have to eat, you know.
Lead 3: Yes. So if there is a high viral load in the room –
Professor Clive Beggs: Yeah.
Lead 3: – one way of preventing you from contracting the infection is mask wearing?
Professor Clive Beggs: That also helps to keep the viral load down.
Lead 3: I know, I know, but the other way of helping reduce the viral load is therefore ventilation?
Professor Clive Beggs: Absolutely.
Lead 3: Right. Can we just deal with some terminology in relation to ventilation?
Professor Clive Beggs: Yep.
Lead 3: Ventilation is the introduction of fresh air to flush away bacteria?
Professor Clive Beggs: And viruses.
Lead 3: I’m taking your words.
Professor Clive Beggs: My words, all right.
Lead 3: And viruses.
Professor Clive Beggs: I obviously was talking about bacteria there.
Lead 3: All right.
Professor Clive Beggs: But ventilation is – yes, it is.
Lead 3: Thank you.
Professor Clive Beggs: No, ventilation is the action of introducing fresh air, outside air that’s clean to – what we do is we dilute the concentration and we flush away the particles in the air. So it flushes away anything that’s in the air, as aerosols, so that could be dust, that can be, you know, inanimate stuff, it can be bacteria, fungal spores and viruses, right? So it’s indiscriminate. It flushes that away.
Lead 3: I follow that. Let’s just concentrate on the virus for these purposes. Air conditioning is the movement of air around or between rooms; it’s not the same thing as ventilation, is it?
Professor Clive Beggs: Air movement is the movement of air around between spaces so, in this room, for example, we could have a ceiling fan – we haven’t got one, you’ll have to imagine it – it would be moving, you would feel the air currents generated by that, but that’s not ventilating the space, it’s promoting movement, and many people get confused between the two.
Lead 3: Air cleaning is the process by which the air is cleaned, as the name suggests, with a filtering unit?
Professor Clive Beggs: Yes, absolutely, so that does move – we’ve got one over there.
Lead 3: We’re going to come onto that later.
Professor Clive Beggs: It’s got a fan and air goes through it. So it promotes air movement but it cleans the air.
Lead 3: All right. Now, can I ask you please to look at paragraph 238 on page 90 of the report. Dealing now with ventilation.
Professor Clive Beggs: Yep.
Lead 3: Paragraph 238, you say at the top of the paragraph that room ventilation is ineffective against large droplets, ie those greater than 100 microns, because they behave ballistically and drop to the floor.
Professor Clive Beggs: Right.
Lead 3: Is that correct?
Professor Clive Beggs: Yes. Sorry, general room ventilation that we normally have, that you can have specialist systems that do do that but that’s a different animal. But, yes, it is correct.
Lead 3: You go on there to, in that paragraph, make the point that ventilation can only flush away and remove aerosol particles that are suspended in air as these travel with the air currents?
Professor Clive Beggs: Absolutely, if it’s headed for the floor and it’s heavier, it’s not going to be flushed away.
Lead 3: “With respect to this, room ventilation is generally only effective at mitigating the far-field infection risk, because it cannot remove aerosol particles in the near field …”
Professor Clive Beggs: Yes, yes definitely. Again, there are very specialist ventilation systems that could do the near field but, generally speaking, it only affects the far field, it flushes out the particles and reduces the concentration.
Lead 3: “So, in IPC terms, room ventilation is a measure designed to mitigate the transmission of disease by the airborne route.”
Pause, please:
“Therefore, there is an inherent inconsistency in saying that room ventilation is important, which simultaneously arguing that airborne transmission does not occur.”
Professor Clive Beggs: Yeah.
Lead 3: “This is something that many may fail to appreciate.”
Put that into layman’s terms, please.
Professor Clive Beggs: Yeah, I’m not going to mention anybody, I’m talking in general about things, as what happens is that there’s an inherent disconnect between – frankly, you see it all over the place in much of the IPC literature that’s been – certainly in the historically is – people generally think ventilation is a good thing, but then they argue that airborne transmission doesn’t occur, in which case you’d say, “Well, if it’s all droplet, why on Earth we need the air – why do we need the ventilation?” And, you know, it’s a – they’re contrary positions and they say, “Oh, well, it’s good to have it”, and then, well, if it’s good to have ventilation, you’re arguing that there’s things in the air and they could be breathed in.
So people don’t fully connect these – join the dots, if you know what I mean.
Lead 3: I mean, you’re never saying you should only have masks or you should only have ventilation, that’s not what you’re saying, if I’m following?
Professor Clive Beggs: Certainly I’m not saying that, no. I am saying – I’m just saying that there’s a disconnect in – you need a holistic approach, you need to look at all the routes and you need to have something that’s workable.
Lead 3: Now, at your paragraph 240, you set out the ways in which engineers quantify the amount of ventilation required to minimise the risk of airborne transmission, air changes per hour, and you say there it’s the number of complete air changes, so the replacements of air that will occur in one hour. Just help us with the example that you set out there.
Professor Clive Beggs: Yeah, right, so we’ve got a room here. Let’s say we had two air changes – doesn’t matter what size the room is, let’s say we had two air changes per hour, that’s the usual – ACH is what that means – two air changes per hour, that would mean that the complete volume of the air in the space was replaced twice in an hour. So if we had a particle of air, I know it’s a mixture of air – of gases, but if we had a particle of air, that would mean – or an aerosol suspended in that air, one aerosol, right, one viral particle – on average it would remain in the room for half an hour at maximum, and it would be flushed away.
Lead 3: So six air changes an hour would mean that it remained for ten minutes?
Professor Clive Beggs: Ten minutes, yes.
Lead 3: Right.
Professor Clive Beggs: So that’s the kind of longest. Now, that’s assuming complete mixing. You can have pockets of air which are stagnant and that’s why we need to look at how that’s moving around in the space but that means that, if you’ve got six air changes per hour, generally the particles are not hanging around for a long period in that space and, therefore, if there’s a virus in them, that virus is not having a long time to decay. It’s not like a door handle or something where it might be sitting there for days.
Lead 3: All right. Fresh air rate per person, you set out there. It’s generally specified in terms of litres of fresh air per person per second and so, for example, in a classroom containing 30 people, the fresh air rate of 10 litres per second was specified, you’d need a ventilation rate of 300 litres per second?
Professor Clive Beggs: Yes.
Lead 3: Right. Now, we won’t descend to the arithmetic in a number of circumstances but that’s generally the way –
Professor Clive Beggs: That’s just generally – it’s very useful in situations especially like this room here, where we have quite a high occupancy level. If you have a lot of people in one space, one’s relating to the room, the other’s relating to the people.
Lead 3: I think you make the point in your report that a room can have a region of high and low virus concentration, it’s not one or the other?
Professor Clive Beggs: Absolutely, you showed a picture earlier on which was from a CFD analysis of a ward and you saw that all the aerosols were down one side of the ward and not the other, so that’s because there was a diffuser like this actually dividing the air and concentrating it in that area, and it was kind of circulating round. So we were getting air movement and so it meant that certain people were more at risk than others.
Lead 3: Take another example, there might be a lower concentration by a window that’s open –
Professor Clive Beggs: Yeah.
Lead 3: – than there is at the far end of the room further away from the window?
Professor Clive Beggs: Excellent example because it relates to naturally ventilate spaces. Naturally ventilated spaces are really deep – people don’t realise this but it’s a complex fluid mechanics problem, this space is a very, very deep space and we’ve got some windows. If we were just relying on the windows to produce that, we would have ventilation there but we could have very still stagnant regions over here and it would be difficult. So you can have that but, obviously, also where the infector is, you will have – likely to have a high concentration and if you, again, also have a strong air current, they might be picked up and deposited somewhere.
So understanding how the air moved around wards is quite important, not just specifying the air change rate, in my opinion.
Lead 3: Fine, well, that brings me on to the hospital ventilation guidelines, which start in your report at paragraph 245, and there are what are known as health technical memoranda which are published, and what do they do, in a nutshell, please, Professor?
Professor Clive Beggs: Yeah, these are basically guidelines for all NHS estates and hospital engineers and people involved in buildings. They deal with the ventilation, so ventilating hospital buildings basically, but they’re actually healthcare facilities, so it could be clinics as well, and they’re called specialist ventilation. Most of the concentrated effort is on things like operating theatres, isolation rooms, negative pressure isolation rooms, bronchoscopy suites, things like that.
But they also cover general wards and non-clinical areas, toilets and things like that. Although – so they’re de facto the guidelines that people go to, and there’s two of them: one is for the design of them and the other one – so they specify the air change rates that should be –
Lead 3: Right. Understood.
Professor Clive Beggs: And the other one is for the maintenance and operation, so validating how they run, ensuring that they’re still doing what they’re supposed to be doing.
Lead 3: Now, the HTMs, there are HTMs in England, similar ones in Scotland and I think similar ones in Northern Ireland and Wales; is that right?
Professor Clive Beggs: This is where I’m getting a bit iffy. There are – certainly in Scotland and England there are ones. There’s something governing that in Northern Ireland and Wales, what they’re called, but they’re going to be based on the same kind of standards. Again, engineering physics is much the same and that’s it, yeah.
Lead 3: Now, the HTMs that were in play during much of the pandemic, is that a document from 2007? I’m looking, if it helps you, at your paragraph 247 on page 92.
Professor Clive Beggs: Yes.
Lead 3: The current –
Professor Clive Beggs: Yes, no, I can see that. Right, so, brief history, right? So at the beginning of the pandemic it was the 2007 documents –
Lead 3: Thank you.
Professor Clive Beggs: – that were valid and they went through until I think – is it June 2021 when the new guidelines took over? However, the new guidelines were written before the pandemic.
Lead 3: Right. Whether it’s the 2007 or the 2021 guidance, they broadly used the same distinction between “airborne” and “non-airborne”?
Professor Clive Beggs: Absolutely, they used exactly the same. They’re just slightly modified in various ways but they – from what I can see, but the key thing is they use a rigid decision tree: is the infection likely to be airborne or is it likely to be not airborne – droplet is non-airborne by the way, right, or contact born; and if it’s droplet then it’s just an ordinary ward you don’t have specialist insulation, you don’t have negatively pressurised isolation rooms; if it’s airborne then you need negatively pressurised isolation rooms and various other things. And the only two diseases that are basically classified as being airborne are TB and measles.
Lead 3: TB and what?
Professor Clive Beggs: TB and measles.
Lead 3: Oh, measles. Thank you, I misheard you.
Professor Clive Beggs: Yes, TB and measles are classified. So this classification of whether it’s airborne or droplet is huge in ramifications all the way through the whole thing.
Lead 3: Now, you say at paragraph 249 in your report the HTMs, the 2021 ones, classified spaces within hospitals as either being areas where the risk of airborne infection is high and therefore specialist ventilation is required or areas where the airborne infection risk is low and therefore general building ventilation will suffice. Can you just help us what do you mean by “specialist ventilation”?
Professor Clive Beggs: Right, yeah, so let’s get this the risk is high and low, get that out of the way first of all. If it’s deemed airborne, then it goes down a certain pathway, right? So if it’s airborne, the risk is high, right, by that. If it’s deemed droplet, the risk is deemed low and it goes down a different pathway. So all the specialist stuff kicks in. So there’s really a couple of areas where they consider it really important. I’m talking in broad terms here.
Lead 3: I understand.
Professor Clive Beggs: Yeah, so the classic one is operating theatres because there’s risk of bacterial infections and surgical site infections. So huge amounts of the documents are given over to operating theatres and that’s not really relevant for what we’re talking about here in a pandemic.
The next area is: is it airborne? Well, if it’s an airborne disease like tuberculosis, then the patient should be put in a negatively pressurised isolation facility with a specialist ventilation system that makes sure that there’s an air – a foyer, an airlock that prevents the microbacterium tuberculosis from escaping into the rest of the hospital, so it protects other people.
Lead 3: Understood.
Professor Clive Beggs: Then aerosol-generating procedures, the classic – forgive me, I’m at a loss here but the classic one is a bronchoscopy suite where we actually look – do a procedure with an endoscope to actually take biopsies in the lungs. A lot of coughing, classically done with TB and classically produces lots of aerosols with potentially TB that are infectious. That needs good ventilation, that’s specialist. So you see how the pathway goes down that.
If it’s droplet, you end up on a normal ward, you know.
Lead 3: Yes. So, on a normal ward, not to denigrate it but –
Professor Clive Beggs: So I think six air changes is the specified thing for that –
Lead 3: I’m going to come onto that but I think you make the point at paragraph 250 in your report that, in general, where you are not dealing with those high-risk areas, such as the operating theatres and the like, in general, areas and wards within healthcare systems, odour control is the main reason for ventilation, not infection prevention?
Professor Clive Beggs: So this is the whole point, they basically say – so if you think about the – in the light of the IPC hierarchy of controls, it just doesn’t even figure. This is just saying that the ventilation there is to stop – you know, get rid of smells, basically, no other real purpose, not for infectious purpose, according to this. Obviously it should be for infection control purposes.
Lead 3: So if there were, for example, an asymptomatic patient on a general and acute ward, the ventilation would be doing nothing to try and help dilute the amount of viral load in that ward?
Professor Clive Beggs: Absolutely, not, it would be, no, the ventilation would be there, if it’s six air changes that would be helpful, it’s good but many wards, older wards, don’t even achieve that. But the point is you’re not even recognising it and these are the guidelines. So these guidelines are, in my opinion, out of date.
Lead 3: Fine. Can you help me with that: does the guideline even talk about –
Professor Clive Beggs: It doesn’t, there is no higher risk on normal wards and the only purpose in normal, non-clinical spaces and general wards is about controlling odour, making the place comfortable, and shouldn’t be trying to use too much energy, and patients and healthcare workers are at no higher greater risk. It’s written in my report, I’ve only quoted what they’ve said and, in the light of the Covid pandemic, I’m afraid I don’t believe that’s fit for purpose and I’ve said that – purposely and deliberately saying that, and I’m saying it now purposely and deliberately.
Lead 3: Just a few other matters please on this. I think you have mentioned already that the HTM guidance says six air changes an hour for a general and acute ward but, in your report, you suggest that the evidence shows that the actual ward ventilation rates are lower than that?
Professor Clive Beggs: Yes.
Lead 3: Is that, can you help, is that dealing across the UK or is that based on English studies; are you able to help with that?
Professor Clive Beggs: Yeah, I can, yeah. Right, first of all, we’ve got some a lot of very old hospitals, right? Hospitals are built at different times and they – so, you know, we have Victorian hospitals, Nightingale wards that are just opening the windows, and they’re very prone to whichever way the wind blows, basically, in those situations whether they achieve – you get great variation there in the amount of air changes, as I think I say in my article here. But, for example, the ward that I – I worked closely with Addenbrooke’s Hospital, I’m involved in a study there, but where we measured the rates there, they were considerably lower, I think less than one air change for a mechanical ventilation system – sorry, I need to find the – it’s in here.
Lead 3: You say at paragraph 257, if it helps you:
“Evidence would suggest that” –
Professor Clive Beggs: Could you put this up?
Lead 3: Yeah:
“… actual ward ventilation rates are often well below those specified in the HTM …”
For example at Addenbrooke’s, as you have just been telling us, Butler found delivered mechanical ventilation rates to be between 0.96 and 0.73 air changes on two medicine for the elderly wards, well below what was deemed acceptable in the 1970s and far below the six air changes that we’ve got now in the 2021 HTMs.
Professor Clive Beggs: So this encapsulates what I’m saying here, right? So now, in the current HTMs, it’s six air changes, that’s the standard. When the building was built in the 1970s at Addenbrooke’s in that one, it was 2.5. So that was the standard, it was designed to that, which is considerably lower than what we have now, whether that’s a right standard or acceptable standard is another matter but, even then the – when we actually measured the air change rates from the mechanical ventilation system – and what we do is we actually put a hood anemometer over the grilles to see how much air is being brought out.
We found it was less than one air change so it was not performing to its standard then and way below the other standard. The bottom one there, the Nightingale ward, basically that’s a ward with cross ventilation and lots of windows and no mechanical ventilation and there’s huge variation there because of basically how the wind blows, basically, and whether the windows are open. There are some other – I mean, when I was writing this report, I didn’t –
Lead 3: Can I pause you there –
Professor Clive Beggs: Sorry.
Lead 3: – because I think we’ve got the point there that there is great variation depending on the age of the hospital, type of ventilation they’ve got and the ability to reach now the guideline of the six air changes an hour. But help me about this: what do the HTMs say, if anything, about non-clinical areas and the ventilation that’s required, for example, in a staff room or where the cleaners go to get equipment?
Professor Clive Beggs: Right.
Lead 3: Do they say anything about it?
Professor Clive Beggs: No and yes, right? So largely no, right? But if I can just sum it up, right?
Lead 3: Of course.
Professor Clive Beggs: So the – I’ve given the flavour of what it says. Basically it’s saying these are ancillary places, they’re not that important, right, in terms of the ventilation is for odour control and that. You then have a great long list, so there’s very little on ward ventilation actually written in the text.
What you have is a big table with various spaces listed so, in that table, which covers about four pages, you will have things like ancillary spaces, some will be a sluice thing, a ward toilet, I can’t remember whether there’s an office building, a waiting area, how they gradate it but they’ll have usually something, an air change rate, and, generally, I don’t know I wouldn’t like to comment at this bit but that’s how they treat it; it’s kind of an also-ran space.
Lead 3: Understood. So there is a concentration, if that would be the right phrase on the high risk clinical areas?
Professor Clive Beggs: No, the high risk from according to the criteria of – to me it’s not concentrated on the high-risk areas from –
Lead 3: Do you think –
Professor Clive Beggs: – a Covid point of view.
Lead 3: Sorry, I didn’t mean to cut across you. Do you think that the HTMs in general reflect the risks of transmission from airborne infectious viruses?
Professor Clive Beggs: I don’t think they do at all.
Lead 3: Right.
Professor Clive Beggs: And from what we know and what we know about transmission of Covid, they don’t adequately reflect this. They do put a kind of preamble on them, say we wrote these before the Covid –
Lead 3: I follow that, yes.
Professor Clive Beggs: Which they do stress and, yeah, that’s reasonable, yeah.
Lead 3: Just before we break, if I may, my Lady can I just look briefly please at the interventions that can be used to supplement ventilation and, Professor, it’s dealt with in your report starting on page 97. Obviously opening a window but that is subject to wind direction, strength of the wind, comfort of the patient if it’s winter, that’s probably not going to be hugely practical.
Professor Clive Beggs: Well, can I – I’ll just list them, they’re very useful. Obviously you could open windows. It’s a good way to boost ventilation. But there’s lots of downsides. You’ve mentioned winter. You freeze the patients in winter, that’s not a good situation, especially if these are patients who are very ill and need to be comfortable and maintain their body temperature. You also get pollutants in from outside, you get particulates from traffic, that’s not good for respiratory health at all, fungal particles are not helpful either. Noise, you get noise traffic. You know, there’s a whole load of things and, also, once you’ve opened them, when you’ve got a deep plan space, you can’t necessarily get good ventilation. It’s good in that area but not further in. So there’s limitations. That’s what I would say.
Lead 3: Assuming that we are dealing with not a new hospital but one of the older hospitals in the estate, clearly you can’t rip down the ceiling and redo the ventilation, or not easily and certainly not cheaply in a pandemic.
Professor Clive Beggs: It’s a hugely expensive to change and upgrade ventilation systems, and disruptive as well.
Lead 3: So the kind of portable or easily built into options include portable air cleaners; is that right?
Professor Clive Beggs: Yeah, portable – usually they’re portable but call them supplementary air cleaners, supplementary devices that help to remove pathogens or nullify pathogens in the air. Pathogens, by the way, could be bacteria or viruses.
Lead 3: Fine, and helpfully there’s a figure there giving us an example of what one may look like but it’s easily to put into the ward or the room or whatever you want to …
Professor Clive Beggs: You have several in this room but there’s one there.
Lead 3: Thank you very much. All right. There are what are known as upper room UV lamps. What are they, please?
Professor Clive Beggs: Right, upper room UV, it is a technology where you’re using ultraviolet light, so we can use ultraviolet light at 254 nanometres, that’s UVC light. It actually – when the photons of light hit the virus they actually destroy the genetic material and prevent it from being able to replicate again and cause infection. So upper room UV – you can put UV in air cleaners like that in a box, so they’re doing the same thing as the filter, the HEPA filter, air efficiency filter – other technology is different – or you can actually put them on fittings up onto the ceiling, at high level above people’s heads, you can’t see the actual field, and create a UV field.
Now this is a very old technology that was used in the 1930s and 40s, right up to the ’60s in the States on TB wards, and what you’re doing is allowing the natural air convection currents to take the pathogens and the – in the case of TB, through the field and it’s getting zapped. It’s above the heads of people, so it’s safe and it – you can get a huge air – equivalent air change rate.
Lead 3: So pausing there –
Professor Clive Beggs: So –
Lead 3: – there are a number of ways of trying to improve the ventilation in a ward, in a staff room, if we wanted to, in any number of settings and I think you say that these portable interventions have a role to play in a pandemic because there’s a balance that needs to be struck between ventilation in non-pandemic times and the ventilation that may be required during a pandemic?
Professor Clive Beggs: Yeah, I think this is – well, first of all, I’m not the only one saying this, SAGE EMG said this as well, right? But, to be honest, I actually was – throughout the pandemic, I had a central role in trying to promote this. I could see that no one was doing this so I actually got these trials off the ground at Addenbrooke’s to do that, so I was very much an instigator in trying to promote the use of this and get the trials to get the evidence because I could see that we hadn’t got the evidence.
Going back to what you said, they’ve got huge potential. You’ve got an estate, money’s short, in everything we should be looking at utility. Can we – what can we do, the biggest bang for our buck. So we’ve got wards that we can’t necessarily upgrade the ventilation system and, actually, do we need the – you know, in a pandemic situation, if you’ve got a ward that’s used for cohorting patients, you might need a very high ventilation rate but, when it’s not being used for that, you don’t need as much. You’re not going to change the whole ventilation system for that, it costs a fortune. But you can bring in portable air cleaners and, in theory, achieve the same effect relatively cheaply. They’re very flexible and these are things that should be looked at, in my opinion.
Lead 3: Right.
Professor Clive Beggs: That’s what I’m trying to say.
Lead 3: I think you made reference there to SAGE and they published a report in November 2020 where, effectively, they endorsed the use of portable air cleaners to provide supplementary ventilation in spaces that were poorly ventilated?
Professor Clive Beggs: Absolutely.
Lead 3: Can I just ask you this –
Professor Clive Beggs: It’s a very useful document as well. There was nothing out there before that.
Lead 3: Is this the position: that there were no guidelines to help hospitals as to what type of portable ventilation they should or might think about installing?
Professor Clive Beggs: Yeah. Well, I was looking at this back in 1999 when I first started looking at this. There was no guidelines, that was upper room UV. There has been no guidelines at all until the pandemic. So we knew these technologies could potentially be effective but nobody knew how many facilities should we put in a space, where we should put them to best effect. We still don’t know. It’s a complex fluids mechanics problem.
Lead 3: So is there effectively an ad hoc way that the hospital might decide to do it and it might be done in one hospital and another way in another.
Professor Clive Beggs: Yeah, this is what happened. I can only speak for my experience of what I observed in various places. But people put – they were put in wards but they were sometimes put – not by us in our trial – but sometimes put in corridors, probably having a minimal impact. If you put too small a unit in, it’s not going to have the effect.
Lead 3: Now, pause there because it’s right to note that since the emergency stage of the pandemic finished in May 2023, NHS England produced two technical bulletins which effectively provided some practical guidance regarding the use of filters and UV air cleaning devices; is that correct?
Professor Clive Beggs: They were built on the SAGE initial document, they were very welcome in my opinion because they again brought more, brought it to the forefront and the potential for it but the trouble is that the – right, I’m just going to use a term here – the applied research is not there.
The fundamental research is there, we know that these things kill the virus and clean the air, how to use them and where we should use them to best effect is not – and so the guidelines can only reflect the research. This research should have been done for the last 20/30 years, you know and, because it’s not there, we can’t – we need to do it.
Lead 3: Final question from me on this topic, please, I just want to go back to UV lamps. You mentioned that they obviously may pose a degree of risk to health?
Professor Clive Beggs: I would say that the risk of the upper room UV is, at 254, fairly well known, it’s fairly minimal. The biggest danger there is, if someone does something stupid like climbs on a desk and looks up into the UV, they’re blinded. So they have got baffles to stop people looking inside, so that you’re shielded, you can’t see them. That’s an obvious thing. Also, if there’s a reflective surface that they reflect on to someone, they can irritate the eyes, basically.
The other one, 222 nanometres –
Lead 3: We don’t need to descend to that but, given that there is a degree of risk –
Professor Clive Beggs: Yeah.
Lead 3: – from a UV lamp, do you think there are more advantages to HEPA filters, the portable units, than there are over the UV lamps, if we are looking at proposing one type of portable ventilation over the other?
Professor Clive Beggs: I think that the HEPA filtered portable filter units are an existing, old, mature technology that’s well understood and therefore is ready to go quickly and we should see if we can get as much utilisation out of that. But I also think the potential bang for your buck of, say, upper room UV is well worth looking at. We need some trials to look at that because that might be useful as well.
Ms Carey: I’m going to move onto a different and final topic with the professor.
Lady Hallett: Certainly, I shall return at – let’s say 15 minutes. People can work out what time that is.
(3.13 pm)
(A short break)
(3.32 pm)
Lady Hallett: Ms Carey.
Ms Carey: Thank you, my Lady.
Professor, in your report at part 5, which starts on page 104, you set out key findings which are effectively a summary of all of the detail that you’ve included in the preceding pages, but can I see if I can summarise it further, if I may, and please correct me if I’m wrong but I think your key findings can be summarised as follows: that Covid is transmitted also via the airborne route?
Professor Clive Beggs: Yes.
Lead 3: So we’ve got droplet and airborne and, you would say to a lesser extent, contact and fomite transmission?
Professor Clive Beggs: Yes.
Lead 3: And if you were to be asked whether you think there is more aerosol transmission than droplet transmission, would you able to opine on that?
Professor Clive Beggs: I would most definitely say that I believe there is more aerosol transmission, airborne transmission, than droplet. Precise figures I couldn’t tell you at this moment.
Lead 3: I understand, right.
You consider that the majority of the exhaled viral load is in aerosols, either smaller particles –
Professor Clive Beggs: Yes, I do.
Lead 3: And it’s the aerosols that penetrate deep into the lung?
Professor Clive Beggs: They penetrate up the nose to the receptors and the upper respiratory tract. And the smaller aerosols penetrate deep into the lung, but they penetrate into the respiratory system.
Lead 3: From your perspective, the 5-micron distinction that we looked at earlier does not accord with the physics?
Professor Clive Beggs: Yes, definitely.
Lead 3: And the 100-micron diameter should be the dividing line between droplet and aerosols?
Professor Clive Beggs: In my opinion, that should be the case. Obviously it’s a little bit of a movable feast, depending on things, but basically that’s the – it’s the ballistic to the aerosol –
Lead 3: That’s what I was going to say. And the reason for that dividing line in your evidence is because particles less than 100 microns can travel longer distances, float in the air, whereas over 100 microns they behave ballistically?
Professor Clive Beggs: Yeah. And to add to that, the ones that float in the air can be inhaled.
Lead 3: Yes, quite, thank you.
Professor Clive Beggs: Whereas the others, unless you – it’s very difficult to be inhaled, right.
Lead 3: You consider that to concentrate on aerosol-generating procedures is to lose sight of the fact that not only do some AGPs produce fewer aerosols than coughing but we lose sight of the fact that breathing, talking, shouting, singing are ways of producing infectious aerosol particles?
Professor Clive Beggs: Yes. However, I would like to just add that in saying that I believe that there’s too much emphasis in those guidelines on the aerosol-generating procedures, as opposed to the natural aerosol generated by exhalation, I’m not saying that the aerosol-generating procedures are not important.
Lead 3: I follow that.
Professor Clive Beggs: Yeah.
Lead 3: It wasn’t to diminish them, but it’s to lose sight of all the other ways in which one can become infected?
Professor Clive Beggs: Yes, to just concentrate on their own is incorrect in my opinion.
Lead 3: I think you said to us earlier that good hand hygiene was important but the evidence that it substantially mitigates transmission of respiratory viruses is relatively weak?
Professor Clive Beggs: Yes, it is relatively weaker, looking at the Cochrane reviews and other reviews. Nevertheless, good hand hygiene is good because those other pathogens, bacterial pathogens, MRSA, things like that, so – I’m not against good hand hygiene, it’s very important. And it’s easy, that’s the point, it’s easy utility, you can do it.
Lead 3: Yes, quite.
In relation to asymptomatic transmission, which for these purposes include the presymptomatic stage, you consider that by September 2020 it was clear that there was widespread asymptomatic transmission?
Professor Clive Beggs: Yes. I would say there was a strong body of evidence to strongly suspect that that was – well, no, yeah, it was. And as a precautionary thing we should have been concerned about it. Yeah. To my understanding.
Lead 3: Yes. To final summary by me, whilst the fluid-resistant surgical masks are helpful at reducing exhalation of droplets, they offer limited protection against the inhalation of aerosols?
Professor Clive Beggs: Yes.
Lead 3: Full protection is provided by FFP3 masks but there are practical considerations such as the need to fit test, how comfortable they are, that may limit the utility of the FFP3?
Professor Clive Beggs: Absolutely. They – when fitted properly, they prevent aerosol inhalation and infection by that route, but they’re uncomfortable, they can irritate the skin, there’s a whole load of baggage that comes with them, so utility is not so good.
Lead 3: And finally, as we just discussed before the break, Covid-19 highlighted the need for good ventilation in healthcare settings, and indeed in other settings?
Professor Clive Beggs: Absolutely, absolutely.
Lead 3: Right. Can we turn, then, please, to your recommendations, and, Professor, they are at 112 in your report. Perhaps if we put those up on screen as well it would help those following.
Now, some of these we may have touched upon already in your evidence, but your first recommendation is there needs to be a more multidisciplinary approach taken to future pandemic preparedness by the government, including but not limited to hospital IPC. It should include scientific advice from experts, similar to the SAGE Environmental Modelling Group, but also working on pandemic preparedness as well as the emergency response.
In a nutshell, why do you say that there needs to be a multidisciplinary approach, and who should be part of it?
Professor Clive Beggs: Well, having looked at an awful lot of evidence and read an awful lot of papers and looked at an awful lot of reports, what becomes absolutely clear to me is that some of the fundamental errors, in my opinion, or assumptions, could have been maybe avoided or could have been – things could have been flagged up if people had had the expertise from the – certainly from the engineering/physics background, and understood more about how aerosols behaved. Often people are coming from a – reading what other epidemiological studies have done, their training is in medicine or in microbiology or nursing, and they maybe missed things that I would spot.
So – I’m not saying it’s me, you know, but we need someone – there’s very few people with – I straddle both biology and that, that’s not a common environment, but we need to have people – and there’s a whole raft of people coming through from the pandemic who’ve learned – from the engineering who have gone into this area to look at because of the pandemic, so they’re out there, who have that kind of physical, biological, science side that could give extra expertise. And I think that that would be very useful.
I’ve also added that it should be in preparedness rather than in response.
Lead 3: Yes.
Professor Clive Beggs: So one of the good things that’s come out of the pandemic is a whole load of engineering schools have suddenly woken up to the fact that there is – all the stuff I’ve talked about is actually engineering, and there’s a whole load of PhD students and other people looking at this area, so the expertise in this area has grown.
Lady Hallett: So you’re drawing a distinction between preparedness and response, because Catherine Noakes was part of SAGE, wasn’t she? She chaired the –
Professor Clive Beggs: She was the –
Lady Hallett: – modelling subgroup.
Professor Clive Beggs: Right, this is where I’m at a slight disadvantage, not being an insider in that. I know Cath very well, but she was – I understood that the Environmental Modelling Group was something set up for the pandemic, didn’t have – wasn’t standing. Is it now standing –
Lady Hallett: No, no, it was set up – well, I think it was set up for the pandemic. Certainly it was SAGE’s for emergencies.
Ms Carey: Yes, but EMG was a subgroup of SAGE.
Professor Clive Beggs: Yes, I think it was – well, SAGE goes on, doesn’t it, in various ways, it’s not just for the emergencies, is it? Or have I got that wrong?
Lady Hallett: We’re going down a –
Professor Clive Beggs: Sorry, I’m showing my lack of –
Lady Hallett: It’s all right, it’s just that you’re saying make sure that the likes of you or Catherine Noakes or people with similar specialities are involved in planning not just response.
Professor Clive Beggs: Yes, make sure –
Lady Hallett: I have it.
Professor Clive Beggs: Yes, when you’re preparing for the next pandemic, get people from all disciplines to get a good idea what’s going on. Cath Noakes joined SAGE but not at the beginning, after – I think later on actually as well.
Lady Hallett: We can check her evidence, I’ve already heard from her so we can check it.
Right, Ms Carey.
Ms Carey: Can I ask you, please, you’ve obviously alluded to the fact that at present it’s not able to say “the amount of transmission is airborne, the amount transmission of transmission is droplets”, I don’t want to go over that again, but recommendation iii:
“Much confusion currently exists in the terminology used in the healthcare system guidance from … the UK …”
That’s before you even add the WHO guidance into that. What do you say and how do you say we can resolve differences in terminology?
Professor Clive Beggs: Right, well, first of all, to say the WHO is actually looking into this whole area and is making slow progress from what I can understand on this whole issue, and I think one of the things that we could do is actually education, so that people who are from a clinical background would actually have explaining what an aerosol is and how things work. Then they would have a better understanding and then that would start to bring people together. The problem is that people are often talking about the same thing but using totally different terminology and being totally confused. And with a bit of education …
The problem is that some people are – well, a little reluctant to change their opinions, I think that’s fair to say, you know, but …
Lead 3: How do you think the UK should go about changing the terminology?
Professor Clive Beggs: Well, I think they’ve got it in step with the rest of the world. I don’t think you can do that. But I think this education thing – you know, once people start to understand how these things behave then they think – they realise the need to change that terminology.
That would help people to come to agreement, I would have thought. It’s when people are just looking at their guidelines from their discipline and don’t understand maybe the fundamental physics going on underneath.
Lead 3: You have referred in your evidence already to the fact that you consider there is a need to revise and upgrade the HTM guidelines on hospital ventilation, so I don’t need to ask you about that.
Professor Clive Beggs: I do believe that, yes.
Lead 3: That’s a firm recommendation you make.
Professor Clive Beggs: Yes.
Lead 3: In relation to portable ventilation, as we were just discussing in the break, do you consider there is need for more evidence and indeed guidelines on the deployment of portable supplementary air –
Professor Clive Beggs: Yeah, we –
Lead 3: – devices –
Professor Clive Beggs: These are – you know, certainly portable air filters, HEPA filters, are low-hanging fruit. They’re cheap, easy, we know they clean the air, we know they do a similar job to ventilation. If ventilation is good then portable air cleaners are good. What we don’t know is how many do we put in, where should we put them to best effect. So it’s applied research, which in the big picture of things is fairly cheap. And, you know, it’s quick to do. But we need to know where we should be putting them to get best effect, you know. And that should be reflected in the HTM guidelines as well, because they should be – just as a standard procedure I would say.
Lead 3: You consider there needs to be, at your recommendation vi:
“… a need for further multidisciplinary research to better understand how air and indeed [infectious] aerosols move around hospital wards …”
Professor Clive Beggs: That goes back to the slides that you showed, which showed the aerosols, the particles all on one side of the ward. In other words, we assume – when we talk about air changes and we specify air changes, we assume that it’s all completely mixed and it does the job. But when we do CFD, we suddenly realise: oh, there’s pressure gradients, things are – that diffuser is actually putting the risk up for these people on this side of the room, the aerosols are going out into the corridor. We need to understand how to do that better. Again, it’s applied research.
Lead 3: Fine. Now, that recommendation there you concentrate on hospital wards, but just thinking about all those non-clinical areas.
Professor Clive Beggs: Oh, non-clinical as well.
Lead 3: Would you include those in there, that generally we need to understand how the air moves around the hospital?
Professor Clive Beggs: Yes.
Lead 3: Yes.
Professor Clive Beggs: Yeah, in fact, non-clinical – hospital waiting rooms are really important –
Lead 3: Yes.
Professor Clive Beggs: Waiting areas are really important areas.
Lead 3: The final one I would like to concentrate on before I conclude is masks. Right?
Now, we have, through you, examined the efficacy or otherwise of FRSM versus FFP3, and you’ve mentioned a number of times that there are potential practical problems with widespread use of FFP3: it needs to be fit checked, it’s uncomfortable. It leaves, does it not, staff, patients, whoever wants to wear them, with a slightly binary choice?
Professor Clive Beggs: You’re absolutely right. This was the one thing that, as I – my brief was to look at the science of these things, and as I looked at it – obviously I knew about the science of both masks, but when I looked into how they were being used, under the guidelines, I realised that all we had was essentially, in the NHS, a binary choice: you go down one route that’s respirators, if that’s kind of specified, in which case then it falls under the COSHH regulations and HSE; otherwise it’s surgical masks. And from a point of view of preventing airborne infection, from the science point of view, one is – it’s all or nothing. These – if they’re fitted properly, the FFP3 masks prevent airborne transmission. The surgical masks, there may be a little bit of inhibition, but they’re not that effective, so they allow the aerosols to get through.
And as a scientist that made me think: well, there’s an awful lot in between there, surely we can –
Lead 3: Pausing there –
Professor Clive Beggs: – improve and get something with – can I – I want to say utility, if you don’t mind. These have got good – the surgical masks, good utility but not effective against airborne. FFP3, very effective but not good utility, they’re difficult, they come with baggage, if that …
In the ground there may be an optimum solution that we could achieve.
Lead 3: Let’s look then, please, at what you say on your page 113 at recommendation v, which is a good introduction to this recommendation. There you’ve made the point already:
“… FFP3 provides better protection for [healthcare workers] caring for patients with [Covid] than surgical masks. This raises the questions [as to] whether [the] … (FRSMs) provide adequate protection to [healthcare workers] when caring for Covid-19 patients.”
Or indeed for those who are asymptomatic?
Professor Clive Beggs: Yeah.
Lead 3: “Therefore, barriers in the way of wider respirator use, whether due to guidance, regulation, fit testing, supply or comfort should be addressed urgently by the UK Government to ensure that more effective respiratory PPE is widely available before and during the next pandemic …”
Professor Clive Beggs: Yeah.
Lead 3: “… and that [healthcare workers] are better protected … In particular, consideration should be given to alternative face mask solutions, such as FFP2 masks with ear loops, which offer superior protection against the inhalation of infectious aerosols compared with surgical masks, while being more comfortable than FFP3 … with head straps …”
And of course you don’t need a fit test.
Professor Clive Beggs: Shall I –
Lead 3: Now, yes, let’s break that down. I have an FFP2 –
Professor Clive Beggs: Yep.
Lead 3: – to show an example of a type of FFP2 which is potentially a middle ground between the FRSM –
Professor Clive Beggs: Yeah.
Lead 3: – and the respirator.
Why do you think there should be more consideration given to that middle ground?
Professor Clive Beggs: Right, so this really comes from public health and also from the point of view of reducing nosocomial infections.
First of all, I don’t want to be prescriptive. It’s just that when I looked into this, there was the FFP2 masks with ear loops which was already there, so it was a kind of low-hanging fruit that might be applicable if used in the right way.
So what we have at the moment is we have a binary situation, and when you go to the FFP respirators with behind the head straps, they’re uncomfortable, they need fit tests, you get hot, there’s a whole load of baggage that comes with it which makes them difficult when you’re in a working environment. And they fall under the COSHH regulations, so they need to be fit tested, and there’s a whole load of stuff there.
These don’t stop the aerosols, but in the ground in between, from the point of view – I’m interested in the greatest benefit for the greatest number, right, so the greatest benefit for the greatest – that’s very much like a public health point of view: you’re trying to use interventions that mitigate the transmission. They don’t do it perfectly, but they reduce it.
And when I was looking into this, I was finding studies where people had looked at FFP2 masks with ear loops, especially in Germany, and they were finding that there was a performance that was 50% better than the surgical masks, they were performing much better than the surgical – and these were straight out of the box, without adjustment of the nose loop, and when you adjusted the nose loop you got much better performance. They’re not fit tested.
Lead 3: No.
Professor Clive Beggs: So these would fail as respirators – and we’re not trying to pretend that they’re behaving as respirators, they’re behaving as masks – but potentially that might be a middle ground that’s got better utility, causes less discomfort to healthcare workers, provides better protection against aerosols, and is reasonably cheap and is easier to use.
And I’m not wanting to be prescriptive –
Lead 3: No.
Professor Clive Beggs: – but what I’m saying is this is an area which we should be investigating or the health service should be investigating.
Lead 3: So is your recommendation, in short, that the government needs to investigate that middle ground and whether there is a form of protection, whether it’s FFP2 or not –
Professor Clive Beggs: Yeah.
Lead 3: – that can provide that balance between the higher levels of protection with the added uncomfort and all the baggage, as you say, that goes with FFP3 and the lower levels of protection –
Professor Clive Beggs: Absolutely, I’m looking – there will be an optimum sweet spot. And that might not be the same for every environment, and remember it’s got to be taken into account with the viral load in the air. By no –
Lady Hallett: I have the point, Ms Carey, thank you.
Ms Carey: Thank you.
It’s finally this, because there are some questions from the core participants.
Professor Clive Beggs: Right, sorry.
Lead 3: Would you support a recommendation that there needs to be better education about airborne transmission for healthcare workers and those completing risk assessments?
Professor Clive Beggs: Definitely.
Ms Carey: My Lady, that does conclude my –
Questions From the Chair
Lady Hallett: Just before I turn to questions from core participants, I think the vulnerable families wanted to ask you questions, I turned them down, but I’ll ask it in summary because I think they probably go without saying.
If you improve ventilation in hospitals to – and obviously protect, in so doing, clinical and non-clinical staff – it goes without saying, does it not, that you’d also help protect patients?
Professor Clive Beggs: It does, yes.
Lady Hallett: It also goes without saying that the most vulnerable patients would be better protected?
Professor Clive Beggs: Yes.
Lady Hallett: Thank you.
This is a question that I was concerned – thinking about too.
In relation to portable air cleaners, in normal times, ie non-pandemic –
Professor Clive Beggs: Yeah.
Lady Hallett: – do hospitals have these portable air – or are they only brought out in an emergency?
Professor Clive Beggs: As far as I know they weren’t being used but they appeared during the pandemic. But they have been known about for years.
Lady Hallett: But the question is, I mean, do all hospitals have a supply of them? Should we be using them all the time?
Professor Clive Beggs: Sorry, I take that back. I used to be a professor of medical engineering at Bradford University and I certainly was aware that there was units being sold. They were probably being used in operating theatres to provide extra ventilation, so they were being used in certain specialist places. It’s an old and well known technology. And they’re easily obtainable, you know.
Does that answer the question, sorry?
Lady Hallett: I think the answer is that the more of them about even in normal times, the better ventilation you have, the better the chances of patient and healthcare worker safety?
Professor Clive Beggs: Yes.
Lady Hallett: Thank you.
Right. Now –
Ms Carey: My Lady, could I just correct one thing? Professor Beggs was kind enough to indicate there are some revisions to paragraph 18.
Lady Hallett: I’ve got them.
Ms Carey: Your Ladyship will have them, but they’ve not been read into the record and I’m asked to do so. It’s two minor revisions, but essentially the sentence should read:
“… but now in August 2024 he acknowledges that the inhalation of infectious airborne particles, ie aerosols, is likely an important route by which SARS-CoV-2 and other respiratory virus infections can be transmitted.”
And in the final sentence, where it currently reads “droplet/aerosol” it should read “droplet/airborne.”
Lady Hallett: Thank you.
Ms Carey: Thank you, my Lady.
Professor Clive Beggs: Excuse me, there’s one thing you missed there, sorry, looking at it, it should be appendix 11A.
Ms Carey: That’s fine, we’ll deal with that. Thank you very much, my Lady.
Lady Hallett: Thank you.
I’m now going to allow some of the core participants to ask you some questions, Professor. They have limited time, so – I often have to say this to witnesses – please remember when giving your answers that the longer your answers, the more you eat into the time that I’ve not so generously allowed them.
The Witness: All right.
Lady Hallett: Right, Ms Foubister, where are you? There you are.
Questions From Ms Foubister
Ms Foubister: Thank you, my Lady.
Professor Beggs, good afternoon, I represent John’s Campaign, Care Rights UK and Patients Association. A lot of our questions have actually been covered, so I anticipate I will be a little bit shorter, you will be pleased to know.
Starting with this one: you explain in your report and you’ve mentioned today certain differences in opinions among scientists, whether between clinicians and physicists or otherwise. When scientists are offering information to government or advising government, do you think that those making decisions should be given an overview of differing opinions?
Professor Clive Beggs: Yes. I think the one thing that’s – it’s not cut and dried, you know, there are quite a few clinicians who also share my viewpoint, they’re not from an engineering or physics background. I think that people need to be aware of the physics underneath it. So you used the word “opinion”. They need to be – a lot of this is known, it’s fact, it’s well understood about behaviour. They need to be aware of these things underlying things, then that will influence their opinion on the epidemiological evidence. Does that make sense?
Ms Foubister: Yes, it does, thank you.
Professor Clive Beggs: Yeah, so I think they definitely need to be aware of the science. So if, for example, I’m not trying to give any real situation, but if you have someone who’s from a public health background and they’re talking about airborne transmission, they will talk about what they’ve learnt and what they know from the textbooks and the epidemiological trials but they won’t necessarily talk about thermal plumes or any of the stuff that I’ve been talking about here, and so it’s very helpful to have that knowledge as well, so that you can interpret the epidemiological data.
Ms Foubister: That feeds into your recommendation about having a multidisciplinary approach?
Professor Clive Beggs: Yes, that’s why, hence why I’ve said it.
Ms Foubister: Thank you.
Onto another question. If I could ask you to look at page 65 of your report at paragraph 165 – it’s right at the bottom of the page –
Professor Clive Beggs: Yeah.
Ms Foubister: – if we can pull that up or if you just have it in front of you.
Professor Clive Beggs: Where is it, 65?
Ms Foubister: It’s now on the screen, I think.
Professor Clive Beggs: What is it, 165?
Ms Foubister: Paragraph 165, so the paragraph starts, and here you say that there were studies that showed that most of the virus was in smaller –
Professor Clive Beggs: Yeah, yeah.
Ms Foubister: – respiratory particles. The second sentence from the bottom, so you did touch on this briefly already but this is just to pick out a particular point, you say that:
“The authors of the PIP report were aware of Lindsley et al’s findings and commented on them in their report. However, their conclusions downplayed [those] findings in favour of the assumption that most of the viral load is in the larger droplets.”
So I have two questions.
Professor Clive Beggs: Yep.
Ms Foubister: The first is that, based on the knowledge available at the time, should the authors of the PIP report have given more credit to the Lindsley report, or taken it on board more rather than downplayed it?
Professor Clive Beggs: They looked at – they were reporting the consensus at the time was that the virus was in the larger droplets, rather than the small aerosols. Lindsley had just come out, and I think they should have taken more notice of that because this was actually hard evidence, this was actually experimental evidence which undermined an assumption – an assumption, the assumption – I don’t think there’s any evidence out there for the virus being evenly distributed throughout all the respiratory particles in the large droplets. I’m not aware of it, it’s always been an assumption that’s been repeated from way back, and here was some hard evidence coming out saying, no, it’s in the small aerosols. Well, you’ve got an experimental evidence against an assumption, therefore, in my opinion, yeah, I probably should have given more weight to that but I’m not going to be too harsh on that, it had just come out, you know, there was a lot of other evidence and that, that they were –
Ms Foubister: Understood.
Professor Clive Beggs: – dealing with and, you know, perhaps they were being cautious. That’s what I would say.
Ms Foubister: If that report hadn’t been downplayed so much, do you think that might have made a difference to the thinking about the transmission of Covid-19?
Professor Clive Beggs: Undoubtedly, undoubtedly, because that would have immediately undermined the assumption of the droplets, as far as I’m concerned and, you know, all – there’s numerous studies now, they’re all in the public domain, and you can see that the viral material, the RNA and live viruses, the bulk of it, over 80% is in the small aerosols in some of these studies, implying that they’re coming from different places in the lungs. That would have had a profound difference to that – that preparedness.
Ms Foubister: Thank you. Those are all my questions.
Thank you, my Lady.
Lady Hallett: Thank you very much, Ms Foubister, I’m very grateful.
Mr Thomas?
Questions From Professor Thomas KC
Professor Thomas: Professor Beggs, you will be pleased to know that one of the questions that I had you’ve already answered, and forgive me for the positioning.
I’m representing and asking questions on behalf of FEMHO, the Federation of Ethnic Minority Healthcare Organisations and just, to give you a little bit of context, FEMHO’s deeply concerned about the challenges surrounding infection prevention and control, particularly the disproportionate impact it had on black, Asian and minority ethnic healthcare workers and patients.
So with that context in mind, let me ask you the one and only question that remains, and it’s this: in your report, at paragraph 229, you reference the SAGE report, Masks for Healthcare Workers to Mitigate Airborne Transmissions of the SARS-CoV-2 Virus, published in April 2021, which places good ventilation above the use of surgical masks in the hierarchy of controls.
Question: considering this, do you believe that reducing viral load in the room air in healthcare settings should be and should have been prioritised above the use of surgical masks?
Professor Clive Beggs: Yes, and that’s what they are implying there but, as you saw from the guidelines, which were written before the pandemic, it wasn’t on the radar in, other than a few places.
So from the point of view of people that you’re representing, this is hugely important because, wherever they’re working in the hospital, whether in a clinical capacity, frontline facing –
Professor Thomas KC: Yes.
Professor Clive Beggs: – patients or in a more ancillary capacity, they were exposed to potentially aerosols that are produced, and therefore at least – I’m not saying that the guidelines were wrong in terms of the ventilation rates, if they’ve been applied or applied, what I’m saying is it should be recognised in the guidelines.
However, they were written before the pandemic and that’s why they need to be updated completely. But it’s very important that it’s not just the clinical spaces, it’s the whole of the hospital, if that makes sense.
Professor Thomas: It does, thank you.
My Lady, Counsel to the Inquiry has already answered the second question, so I don’t need to ask that one. Thank you.
Lady Hallett: Thank you very much, Mr Thomas, very grateful.
Mr Marquis?
Questions From Mr Marquis
Mr Marquis: Professor, I ask very few questions on one specific topic. I ask them on behalf of the Frontline Migrant Health Workers Group.
To help orientate you, it’s page 32 of your report, paragraph 78, and it’s the section of your report that deals with the risk of inhaling an infectious dose.
Professor Clive Beggs: Yep.
Mr Marquis: So if I can just recap the evidence you gave this morning, really to contextualise my question but also to save some time, because I have limited time. The risk of becoming infected increases with the amount of particles in the air, ie the concentration?
Professor Clive Beggs: The risk of becoming infected increases with the increased number of particles that you inhale. So if you’re in – in somewhere with a high concentration in the air, so the risk goes up when there’s more in the air, yes.
Mr Marquis: Exactly. The second risk is it goes up also with the volume of air that one inhales?
Professor Clive Beggs: Yeah, so if you’re in a gym and you’re working out on a treadmill, you’re going to – you know, a huge amount more air is being inhaled and so therefore if there’s a high concentration, you’ll be taking a load more viruses in. But this does apply in a healthcare setting to people who are actually doing more manual work, pushing loads, I assume someone like a porter would be affected by this. They would be working harder in that situation, so their lung capacity would go up in that, yep.
Mr Marquis: Exactly the point, it’s on the physical exertion point that you make reference to in that paragraph.
When you exert yourself physically, it has a significant difference in respect of the volume.
Professor Clive Beggs: Yeah –
Mr Marquis: Can I give you the example that you use in your report, perhaps to save a little time?
Professor Clive Beggs: Yeah.
Mr Marquis: A resting healthy adult –
Professor Clive Beggs: That’s –
Mr Marquis: – inhales 69 litres of air a minute.
Professor Clive Beggs: Yeah.
Mr Marquis: The same adult, walking at a moderate pace, inhales between 20 and 40 litres in –
Professor Clive Beggs: Yeah, and someone doing hard exercise, I think it goes up tenfold, yeah, it greatly increases. So, therefore, if you’ve got particles in the air, you’re sampling them at a faster rate.
Mr Marquis: Three minutes to go, Professor.
You say that physical exertion is the infection risk that is often overlooked. Now, do you mean overlooked from an IPC perspective or just generally?
Professor Clive Beggs: I think both actually.
Mr Marquis: Okay, thank you, I’ll park that there if I can.
So, as a risk factor, exertion, you’ve mentioned porters, porters who are lifting and moving patients and cleaners who are doing the physical labour of cleaning, that would have an implication in terms of infection, both near field and far field?
Professor Clive Beggs: Both near field and far field, the only mitigating thing against that is they may not be in that place for that long, especially porters. They may be in to collect the patient and then out, so their duration would be less. However – maybe also for cleaners, but then some people may be in the space for longer.
Mr Marquis: Well, quite. If we take, as an example, a cleaner, would you agree that a cleaner who’s working longer hours, moving between wards, Covid and non-Covid, and the non-clinical spaces that we’ve referred to in your evidence today would be at a high risk precisely because their duration is increased and their exertion is increased?
Professor Clive Beggs: You’d have to do the calculations, but in theory, that could happen, yes. What I do is I do calculations and I do the sums and then see how that works out, how many likely viral particles that go in an inhale. But those are all factors.
In simple terms, the more you inhale, the higher the concentration; the longer you spend in there, the greater the risk. That’s –
Mr Marquis: All things being equal, the longer the shift and the harder the work –
Professor Clive Beggs: Absolutely, if you’re –
Mr Marquis: – the higher the risk?
Professor Clive Beggs: – in there – yeah. Yeah.
Mr Marquis: Thank you very much, Professor.
Lady Hallett: Thank you very much, Mr Marquis, very grateful.
Right, I think that completes your evidence, Professor Beggs.
It’s been a long day for you. I hope –
The Witness: Thank you.
Lady Hallett: – it’s not been too tiring. It’s been extremely helpful –
The Witness: Thank you.
Lady Hallett: – and some very interesting points that you’ve made. And I’m very grateful for all your care in preparing your report and of course in giving your evidence today.
The Witness: Thank you.
Lady Hallett: Thank you for your help.
(The witness withdrew)
Lady Hallett: Right, 10 o’clock tomorrow.
Ms Carey: Yes, thank you, my Lady.
(4.10 pm)
(The hearing adjourned until 10 am on Thursday, 12 September 2024)