Transcript of Module 1 Public Hearing on 15 June 2023
(10.00 am)
Lady Hallett: Good morning.
Ms Blackwell: Good morning, my Lady. The gentleman in the witness box is Professor David Heymann CBE. May he be sworn, please.
1. Professor David Heymann
PROFESSOR DAVID HEYMANN (sworn).
Questions From Counsel to the Inquiry
Ms Blackwell: Thank you, Professor.
I’d like to begin by thanking you for all of the assistance that you’ve given so far to this Inquiry.
During the course of my questioning this morning, please keep your voice up and speak into the microphones so that the stenographers can hear you clearly. They’re preparing a transcript of your evidence.
If I say something that you don’t understand or you can’t hear, please ask me to repeat it, and I’ll do the same for you.
There will be breaks during the course of your evidence, but if at any time you require a break, please just say so.
Professor David Heymann: Thank you.
Counsel Inquiry: Professor, you have provided a report during the course of preparation for this Inquiry.
Could we please put it up on the screen. Thank you very much. It’s, for the record, INQ000195846.
This is the first page of your report. We can see, Professor Heymann, that it’s signed by you on 19 May of this year, and you have signed the author statement confirming that it’s your own work and that it’s true to the best of your knowledge and belief. Is that still the case?
Professor David Heymann: It’s still the case, yes.
Counsel Inquiry: Thank you very much. We can take that down.
Dealing next with your qualifications and extensive career history, and I’m only going to concentrate for the time being on the highlights as they are relevant to this Inquiry, you are a trained medical doctor, obtaining your BA and MD in the United States, and you have a diploma in medical epidemiology from the London School of Hygiene and Tropical Medicine.
In 1976 you worked for the US Centers for Disease Control investigating the first Ebola outbreak in the Democratic Republic of the Congo in 1976. You then worked in your first stint for the World Health Organisation between 1989 and 2009, and during that 20-year period you headed the World Health Organisation global response to SARS-CoV-1, the Severe Acute Respiratory Syndrome.
Then in 2009 you worked for the United Kingdom Health Protection Agency as a non-executive chair, working closely with the chief executive during the response to the H1N1 influenza pandemic that we know as swine flu. You then transferred to Public Health England in 2013, again as a non-executive chair, and during your stint there you accompanied the PHE team in 2014 to the Kingdom of Saudi Arabia to discuss and review the data on the Middle East Respiratory Syndrome CoV outbreak, we know that as MERS, and to offer technical support during that investigation.
You have more recently been working again with the World Health Organisation, and from 2017 you have been the chair of the Strategic and Technical Advisory Group on Infectious Hazards and you are currently Professor of Infectious Disease Epidemiology at the London School of Hygiene and Tropical Medicine. That brings us up to date, thank you.
Over the course of your career you’ve published over 275 peer reviewed articles and book chapters on communicable diseases, and you are the editor of the Control of Communicable Diseases Manual.
In preparing your report for us, Professor, you have also provided at the end of the report a bibliography and list of references, we don’t need to go to that now, but you have also been good enough to consider additional material which the Inquiry has obtained during its preparation for these hearings, a list of which has been provided to core participants and some of which I will take you through during your evidence this morning.
In terms of the scope of your report, that is set out in a series of instructions which appears at annex 2. Again, we don’t need to go to it now, but in summary you have been asked to assist in the following areas: the virology of coronavirus viruses and an explanation of the difference between SARS type viruses and other viruses, including influenza; the epidemiology of Covid-19, that’s SARS-CoV-2 virus, including its zoonotic origin and its first detection; and an explanation of the method by which Covid-19 is transmitted and how our understanding of that has changed over the course of time.
You have also been able to identify and provide descriptions of some of the UK bodies concerned with threats, and some international organisations dealing with the global assessment of public health emergencies.
All right. Well, having dealt with all of that, let’s start with the basics, please, Professor Heymann.
What are coronaviruses?
Professor David Heymann: Well, coronaviruses are viruses, and viruses, unlike bacteria, cannot be seen under a routine examination with a light microscope, they need an electron microscope. They’re very tiny particles that can only be visualised that way.
A coronavirus is like a sphere surrounded by fatty material, and inside that sphere is the genetic material of the virus, the RNA, ribonucleic acid.
Counsel Inquiry: Yes.
Professor David Heymann: On the surface of that fatty material ball, there are spikes, which are protein, and those are the spike protein of the coronavirus, and those spikes are what hooks on to a receptor on a human cell. To reproduce, a virus has to use that receptor – shall I continue?
Counsel Inquiry: Yes, please.
Professor David Heymann: To reproduce, a virus must enter the cell through the receptor.
Counsel Inquiry: Yes.
Professor David Heymann: Then it takes over the mechanism of the cell and reproduces itself using the cell’s reproductive mechanisms.
Counsel Inquiry: All right. And the spikes that you have described, do they have the appearance of a crown, and is that the reason why it’s called coronavirus –
Professor David Heymann: That’s exactly right, yes.
Counsel Inquiry: – “corona” being that of a crown? Right, thank you.
How many types of coronavirus are there in animals?
Professor David Heymann: Well, it’s not known exactly, but there are probably over 200 coronaviruses that are around the world. It’s a very common virus in the animal kingdom.
Counsel Inquiry: We heard yesterday from Dr Charlotte Hammer and Professor Jimmy Whitworth that, so far as animals are concerned, coronaviruses appear to be common in bats and cats and camels; is that right?
Professor David Heymann: That’s right. They’re in many, many animals, including – even whales, for example, also have coronaviruses. So they’re a very common virus in the animal kingdom.
Counsel Inquiry: Are they common in domesticated animals?
Professor David Heymann: They have been shown to be able to infect domesticated animals. It’s not believed that they are common in domesticated animals, except for animals that are raised in animal farms where there isn’t proper sanitation.
Counsel Inquiry: All right. Well, we’ll come to deal with those farms and wet markets in a moment.
Professor David Heymann: Okay, yes.
Counsel Inquiry: For how long have coronaviruses been present in animals?
Professor David Heymann: Well, it’s really not known. They were first identified in humans, for example, back in the 1960s.
Counsel Inquiry: Yes.
Professor David Heymann: And it’s known before then that they were in animals and that sometimes they caused outbreaks of infection in animals. But it’s only recently, since the coronaviruses of the 21st century, SARS, for example – SARS coronavirus 1 –
Counsel Inquiry: Yes.
Professor David Heymann: – that it’s really been intensively studied in animals.
Counsel Inquiry: All right. How easily do they transmit between animals and between species of animals?
Professor David Heymann: They transmit fairly easily between animals in the same family. We know that from studies that have been done with camels, for example, studies that have been done that showed that minks were able to transfer coronaviruses to each other, and it’s known that they can transmit fairly easily in the animal kingdom.
Counsel Inquiry: Is the transmissibility between animals any indication of the ability or likelihood that a coronavirus can jump the species barrier between animals and humans?
Professor David Heymann: Well, jumping the species barrier is a very complex issue, really. There have to be a series of risk factors that line up in such a way that this jumps the species barrier.
So coronaviruses do, from time to time, jump the species barrier, and when they do – other viruses as well – it’s not known what they will do in humans. Sometimes a virus enters humans and goes no further. Rabies is a good example. From a dog to a human.
Other times a virus can enter humans, like the Ebola virus, or some other virus, cause a small outbreak, disappear and then re-emerge.
Finally, some, like HIV in the last century, emerge from animals into humans and then they become endemic, a regular virus within humans.
Counsel Inquiry: Right.
Professor David Heymann: In fact, all infections in humans are thought to have come at one time or another from an animal, including tuberculosis, including many common diseases.
Counsel Inquiry: So what are the common risk factors that need to align in order to cause a spillover, or a zoonosis, into humans?
Professor David Heymann: Well, those risk factors depend on many different situations, really. The risk factor may be that the animal is infected, that it’s been intensively raised in animal farms –
Counsel Inquiry: Right.
Professor David Heymann: – and then people who are working on those farms could become infected, or if the animals that are sent to a live market, then people who purchase those animals could be infected.
It’s not known what all the risk factors are, but what is known is that the animal and human kingdoms have to be maintained separate as well as possible.
Counsel Inquiry: All right, thank you.
One of the documents that you’ve been good enough to look at is a witness statement that has been provided to the Inquiry by Professor Mark Woolhouse. In his book The Year the World Went Mad, he says that new human viruses usually come from animals and most of them don’t spread well between humans. Do you agree with that?
Professor David Heymann: Yes, I do.
Counsel Inquiry: All right. He also says that coronaviruses are generally more transmissible amongst humans compared with other zoonotic viruses, and that is why they were high on the list of viruses to worry about; do you agree with that?
Professor David Heymann: They do transmit fairly easily in some instances, but some coronaviruses don’t transmit easily from human to human.
It depends where they reproduce in the human. If they reproduce low in the lungs, then it takes a deep cough or a medical procedure that causes droplets to transmit. If they reproduce in the upper nasal passages, then it’s very easy to transmit. So they’re not all the same.
Counsel Inquiry: Right, so there is a variance.
Could you explain to us, please, the process by which a virus becomes endemic in humans?
Professor David Heymann: A virus becomes endemic when it spreads throughout human populations and is able to sustain its transmission from human to human.
Counsel Inquiry: Yes, okay. What factors might contribute to a virus becoming endemic?
Professor David Heymann: It’s a characteristic of the virus, for one thing –
Counsel Inquiry: Yes.
Professor David Heymann: – that virus, its transmissibility, its ability to transmit. It’s also the population which is infected: if it’s receptive to the virus and doesn’t have protection against it, it can transmit. If there’s a population that has solid immunity against a virus, then it can’t transmit further.
Counsel Inquiry: Right.
You were good enough in the course of your report to describe to us the four coronaviruses which are endemic in humans. For the record, they are 229E, NL63, OC43, and HKU1.
What do those letters and numbers mean? Is there any format behind the nomenclature?
Professor David Heymann: There is clearly a format behind them, and it depends on when they were named what that format was.
Counsel Inquiry: Right.
Professor David Heymann: There is an international taxonomy group which does name viruses and they have altered the way they do that periodically. So I can’t exactly what each one means, but they do have a name and that name is with them today.
Counsel Inquiry: All right, thank you.
How severe or how mild with the upper respiratory infections caused by those coronaviruses?
Professor David Heymann: Those coronaviruses generally cause a common cold.
Counsel Inquiry: Right.
Professor David Heymann: They’re common cold viruses.
Counsel Inquiry: So fairly mild?
Professor David Heymann: They’re fairly mild, except in some people who might have comorbidities or the elderly, who are debilitated because their immune system is not responding the way to should.
Counsel Inquiry: What about young children, are they more at risk?
Professor David Heymann: Young children are not considered to be at great risk from human coronaviruses but they do get common colds and those common colds are coronavirus sometimes.
Counsel Inquiry: All right. What treatments or vaccines are available for those four coronaviruses?
Professor David Heymann: Well, there are no vaccines available. In fact they’re considered to be very mild viruses.
Counsel Inquiry: Yes.
Professor David Heymann: So the usual remedies that are used to treat a common cold are used to treat them.
Counsel Inquiry: What are the routes of transmission for them?
Professor David Heymann: The routes of transmission are from the nose or the nasal passages through a sneeze or a cough onto another person, droplets and particles, aerosolised particles.
Counsel Inquiry: How long would it take for there to be long-term immunity from those four coronaviruses?
Professor David Heymann: Well, long-term – I’d rather talk about population immunity. Population immunity is when the majority of the population has had infection, has developed antibody or response to that.
Counsel Inquiry: Is that also sometimes known as herd immunity?
Professor David Heymann: They’re different. Herd immunity is an immunity which protects against reinfection.
Counsel Inquiry: Yes?
Professor David Heymann: Or it’s a vaccine that protects against infection. And with the SARS Coronavirus 2, we don’t have either of those factors available. So in fact herd immunity at present cannot be established from the SARS Coronavirus 2.
Counsel Inquiry: What’s the difference between that and population immunity?
Professor David Heymann: Population immunity is general understanding of all the population immune systems of the virus, with a response with antibody usually, and therefore that population immunity, in the case of the SARS Coronavirus 2, prevents serious illness and death in most people.
Counsel Inquiry: Right.
I’d like to ask you some questions now about the procedure that you set out in paragraphs 18 and 19 of your report. We don’t need to look at them, but it’s the molecular clock analysis that was taken of coronavirus OC43.
First of all, Professor, can you explain to us what the molecular clock analysis is.
Professor David Heymann: Yes. Molecular clock analysis is an attempt to understand the rate of mutation of a virus.
Counsel Inquiry: So from the animal into the human?
Professor David Heymann: No, the rate of the mutation in a human or –
Counsel Inquiry: Within a human, right, okay.
Professor David Heymann: Yes. Now, what was done in 2004, and which was very important to note, is the fact that a group of molecular biologists calculated a rate of mutation of human coronavirus, the SARS coronavirus – no, I’m sorry, human coronavirus OC43.
Counsel Inquiry: Yes.
Professor David Heymann: They calculated that rate of mutation by taking all the known specimens that they could find of OC43 virus from 1950s onward, they genetically sequenced them, and each one had a slight difference in its genetic structure, and that’s a mutation.
Counsel Inquiry: Yes.
Professor David Heymann: So they calculated a rate of mutation of that virus going forward to 2003.
Counsel Inquiry: Yes.
Professor David Heymann: They did the same thing with the virus that comes from cattle, because cattle were the source, or the expected source, of OC43 –
Counsel Inquiry: Originally?
Professor David Heymann: – in humans – yes.
Counsel Inquiry: Yes.
Professor David Heymann: So they calculated a rate of mutation in cattle as well. Then they took those rates of mutation and worked them backwards from the present time –
Counsel Inquiry: Yes.
Professor David Heymann: – to where both of those viruses would have looked the same, where they wouldn’t have mutated, and that occurred between 1850 and 1890.
In 1888/1889 there was a pandemic called the Russia influenza, and these molecular biologists hypothesised that this was the emergence of OC43 because the pandemic that occurred was not exactly what occurs with influenza. There were many deaths, a million deaths in a very small world, but it caused neurological symptoms in most persons.
Counsel Inquiry: Right.
Professor David Heymann: So they hypothesised that this was the emergence of OC43, which then became a virus which causes the common cold today, because of population immunity, which is protecting against serious illness and death.
Counsel Inquiry: So by using the molecular clock analysis they were confident, to within a certain time period, of when the disease jumped into the human population?
Professor David Heymann: That’s correct. They used three different methods, and they came out with the same with each of these methods.
Counsel Inquiry: Right. Has that procedure been undertaken in relation to what we now know as Covid-19?
Professor David Heymann: There was an attempt by some molecular biologists in the US to calculate – to do a molecular clock analysis of SARS Coronavirus 2.
Counsel Inquiry: Yes.
Professor David Heymann: In doing their analysis, they went backwards from the time when it was first identified to where it might have been very close to the virus that’s similar in bats, and they came to about a period of October 2019.
But this is just one of many hypotheses, as you know.
Counsel Inquiry: Yes. Thank you.
I’m now going to ask you a series of questions about 20th century coronaviruses, so we’ll start with SARS, move on to MERS and then finish with Covid-19.
At paragraph 21 in your report you tell us that SARS is thought to have emerged from an animal, likely to be a civet cat, in a live animal market in the Guangdong Province of China sometime late in 2002; is that right?
Professor David Heymann: That’s correct, yes.
Counsel Inquiry: Is it thought to have resulted from a one-time mutation of the virus, reproduced either in the animal host before transmission to humans or in humans after the emergence had occurred?
Professor David Heymann: That’s correct, yes.
Counsel Inquiry: Is it right that the presence of antibodies in the blood of workers in live animal markets suggests that they had previously been infected with other coronaviruses which had not gone on to transmit human to human?
Professor David Heymann: That’s correct. That comes from a study which was done by Chinese after the SARS outbreak in 2003.
Counsel Inquiry: Right. From the live animal market in Guangdong, SARS went on to spread amongst health workers in provincial a health facilities, through a combination of close physical contact with infected patients and medical procedures that cause pulmonary aerosols; is that right?
Professor David Heymann: Yes, that’s correct. The Chinese were never forthcoming at the beginning with their information, but this is the assumption.
Counsel Inquiry: Right. What sort of medical procedures produce pulmonary aerosol?
Professor David Heymann: When there’s a severe respiratory infection such as SARS coronavirus, there is a lot of mucus that builds up in the lungs.
Counsel Inquiry: Yes.
Professor David Heymann: To get that mucus out, to help the patient breathe easier, there is an infusion through the nose and a tube of saline, which is salt water, a –
Counsel Inquiry: Yes.
Professor David Heymann: – body salt water, and then the lungs are flushed out, the water is pulled out, and along with that is the mucus that’s been softened and absorbed by the water, and droplets are many times caused as a result of that.
Counsel Inquiry: Are the aerosols generated by that procedure the same or smaller or lighter than aerosols generated by normal voice projections, such as speaking loudly or singing?
Professor David Heymann: I think it’s useful to look at an aerosol as being on a spectrum of droplets which are heavy and fall, to lighter particles which are carried by the air, to very light particles. So it’s a whole range of things. And these particles contain virus.
Counsel Inquiry: Right. What stops the virus from spreading?
Professor David Heymann: The virus is able to transmit and cause infection as long as the surrounding material, which is, many times, mucus, is moist.
Counsel Inquiry: Right.
Professor David Heymann: If it dries out, the virus can no longer infect.
Counsel Inquiry: So is that why ventilation assists in preventing transmission, because the air flow will assist in drying out the particles?
Professor David Heymann: That’s correct.
Counsel Inquiry: All right.
At paragraph 21 in your report you say that there was “substandard infection prevention and control” in the Guangdong health facilities. How so?
Professor David Heymann: Well, all we know is that the graph that the Chinese finally produced for this outbreak shows that health workers became infected very early in the outbreak, and those health workers then continued to become infected, and it’s assumed that they infected their family members and other patients. One of those health workers actually came out of Guangdong Province into Hong Kong in February of 2003, and from him the virus was spread to people staying in the same hotel and it spread around the world. So health workers are very important, always, in emerging infections, because they don’t recognise that they’re a new disease oftentimes.
Counsel Inquiry: Yes. Do you know, for instance, Professor, whether or not those health workers were routinely wearing PPE such as face masks or shields?
Professor David Heymann: I think it can be assumed that early on they weren’t, because what the Chinese indicated, when they finally opened up to providing information, is they thought that this was influenza –
Counsel Inquiry: Right.
Professor David Heymann: – and they therefore were not worried that it was a new infection.
Counsel Inquiry: Okay, thank you.
So SARS-CoV-1 was first identified as a novel coronavirus by genetic sequencing in March of 2003, which was about three months after its emergence. Do you have any comment to make on the length of time that it took to identify as a novel coronavirus?
Professor David Heymann: Well, the virus was first isolated from a patient in February –
Counsel Inquiry: Yes.
Professor David Heymann: – in late February, and so it was very rapid, in fact –
Counsel Inquiry: Yes.
Professor David Heymann: – that it was understood that it was a coronavirus.
Counsel Inquiry: Which countries were affected by SARS?
Professor David Heymann: Well, initially there were – about seven countries were infected, because these were people who were stayed on the same hotel.
Counsel Inquiry: Yes.
Professor David Heymann: I think in my testimony I’ve said it went to 21 or 22 different countries. That included countries around the world. The good – if there was good in this outbreak – was that it didn’t appear to make its way into Africa, where surveillance might not have detected it and it might have spread even further than it did.
Counsel Inquiry: Yes. You have described the virus reproducing deep in the lungs, which would require deep coughing or pulmonary procedures to create the droplets or aerosols that you’ve described.
Was that a major factor in the control of SARS?
Professor David Heymann: I believe it was, yes. There were several factors that were important. Number one, SARS Coronavirus 1 is not transmissible, or highly transmissible, until two or three days after the onset of signs and symptoms.
Counsel Inquiry: Right.
Professor David Heymann: Unlike SARS Coronavirus 2.
Counsel Inquiry: Okay. Is that the incubation period?
Professor David Heymann: That’s the period from – no, the incubation period is the period from infection to onset –
Counsel Inquiry: To onset of symptoms, yes.
Professor David Heymann: Yes. So that was one of the factors. It wasn’t transmissible early, after –
Counsel Inquiry: Right.
Professor David Heymann: It was only transmissible after signs and symptoms developed.
Counsel Inquiry: Right.
Professor David Heymann: The second thing, it reproduced deep in the lungs, and therefore was very difficult to transmit. There had to be really deep coughing and close contact with others. Finally, there was a willingness of the world at that time to work together, and so countries agreed not to travel to places where there were uncontrolled outbreaks of SARS Coronavirus 1, which included Singapore, Hong Kong –
Counsel Inquiry: Yes.
Professor David Heymann: – and Canada.
So the outbreak was one that was contained rapidly, and I think you could say that that virus now is gone from human populations. It’s been eradicated.
Counsel Inquiry: Thank you.
During the evidence of Professor Whitworth and Dr Hammer yesterday, we heard about something called the case fatality rate.
Professor David Heymann: Yes.
Counsel Inquiry: Is that the number of confirmed deaths caused by a virus in relation to the number of confirmed infections?
Professor David Heymann: No. Confirmed cases.
Counsel Inquiry: Confirmed cases, sorry.
Professor David Heymann: Yes. Yes.
Counsel Inquiry: The infection fatality rate is less certain because there are those who may be infected asymptomatically, et cetera?
Professor David Heymann: That’s correct, yes.
Counsel Inquiry: So that is not based upon confirmed cases?
Professor David Heymann: That’s correct, yes.
Counsel Inquiry: All right. Now, the case fatality rate of SARS was, you tell us in your report, close to 10%.
Professor David Heymann: That’s correct.
Counsel Inquiry: In comparison to case fatality rates for MERS, which we’re going to move on to in a moment, which was about 35%, and the case fatality rate for Covid-19, which is around about the 1% mark.
Professor David Heymann: Mm.
Counsel Inquiry: Can you explain to us what danger lies in the phenomenon of under-reporting and how that has to be factored in, in determining either the case fatality rate or the infection fatality rate, please.
Professor David Heymann: Yes. Well, in infection fatality rate, it’s very difficult to know all the infections unless you test the entire population.
Counsel Inquiry: Yes.
Professor David Heymann: So the infection rate – case fatality rate would be the number of deaths from that infection based on the whole population that has infection. Case fatality rates are based on a case definition, and a case definition describes what a disease is thought to look like by the persons who develop that case definition, usually the public health community.
Then all cases that fit that case definition must be tested –
Counsel Inquiry: Yes.
Professor David Heymann: – and must be shown to have had infectious agent.
Counsel Inquiry: Is that a laboratory test?
Professor David Heymann: That is a laboratory test, yes. Then the case – the death rate is those people who were shown to be infected who died. So they’re included in the case number –
Counsel Inquiry: Yes.
Professor David Heymann: – but they’re a separate number there, the fatality number as well.
Counsel Inquiry: All right. Now, you’ve described there a case description. Is that the symptoms that have to be present in order for a case to warrant the description?
Professor David Heymann: That’s right. In an outbreak investigation, or whenever there’s a new disease, a case definition is rapidly developed based on what’s known at that time.
Counsel Inquiry: But that would change over time, would it not?
Professor David Heymann: Absolutely, it can change over time, and it generally does change over time.
Counsel Inquiry: All right.
Could we display, please, INQ000198953.
I think you’ve had an opportunity of looking at this before, Professor Heymann. This is a table which has been taken from a video lecture that Professor Chris Whitty gave to Gresham College, London, on how to control a pandemic, in 2018.
Now, if we just familiarise ourselves with what we have. The vertical axis shows the level of transmission and the horizontal axis shows the level of mortality.
If we start from the least serious moving up to the most serious. Bottom left-hand corner, low transmission and low mortality, the box in green, Professor Whitty has said “Not worth worrying about”. So that is the least serious part of the table, isn’t it? If a pandemic is thought to have low transmission and low mortality, that’s the least serious of the four that we see here.
The next in seriousness is the box above, so the yellow box above, which is high transmission but low mortality rate; do you agree with that?
Professor David Heymann: Yes.
Counsel Inquiry: The example that’s been given here is the H1N1 2009 swine flu, which we see, according to this table, has a mortality rate of 0.3%, but between 10 and 200 million cases, so very high transmission?
Professor David Heymann: Yes.
Counsel Inquiry: Next in line, if we go to the bottom right-hand corner, we can see the pandemic with low transmission but high mortality. In that box the example given is the H7N9 avian flu from 2013 to 2018, with 30% mortality but around 2,000 confirmed cases. So very low transmission there?
Professor David Heymann: Yes. I wouldn’t call this a pandemic, though. This is not a pandemic. This is outbreaks of this disease which occur occasionally. The disease is not pandemic as such in humans, but it is – it appears to be in birds.
Counsel Inquiry: Right, thank you.
Then finally, top right-hand corner, we can see, in the pink box, the pandemic with high transmission and high mortality rate, the example given there is the H1N1 1918 Spanish flu, with around 3% mortality. Do you have any comment to make about that box?
Professor David Heymann: Yes. It’s always been interesting to me to see how virologists and others like to compare the current situation to 1918, which was a pandemic of influenza but which also was an era where there were no antibiotics, and although antibiotics will not clear influenza, they will clear superficial bacterial infections that occur in the lungs when they’ve been robbed of their lining by influenza virus. So the mortality was high, much of that mortality was likely due to superficial bacterial infections.
So we don’t really know the mortality from H1N1 Spanish flu directly from the virus. We only know that on top of that there were bacterial –
Counsel Inquiry: Okay, so it could have been a combination of the virus and then the bacteria –
Professor David Heymann: That’s generally –
Counsel Inquiry: – effect on top of it?
Professor David Heymann: – the thinking, yes.
Counsel Inquiry: All right, thank you.
Just before we leave this table, are you able to assess where Covid-19 might appear in relation to the level of transmission and mortality?
Professor David Heymann: I would place the coronavirus, SARS Coronavirus 2, on this table – let’s see, I need to think a bit. I will.
I would place this virus, I believe, on the high mortality end, and so I would place it high transmission, high mortality.
Counsel Inquiry: Right. So top right-hand corner in the pink box?
Professor David Heymann: Yes.
Counsel Inquiry: Thank you. We can take that down, thank you.
What are the symptoms and clinical outcomes of SARS, or what were the symptoms and clinical outcomes?
Professor David Heymann: SARS was a very severe respiratory infection which caused respiratory failure. People could no longer breathe.
Counsel Inquiry: Yes.
Professor David Heymann: The outcome of that was that there was a high case fatality rate of 10%, and in addition many people who recovered had what’s called pulmonary fibrosis.
Counsel Inquiry: Right?
Professor David Heymann: Which means that their lungs were replaced – the breathing – the area where oxygen exchange in the lungs occurs was replaced with fibres which didn’t permit exchange of oxygen, and so some of those people still today have severe consequences from having had this infection.
Counsel Inquiry: Are you able to say how the ongoing outcomes of SARS compare to those of Covid-19?
Professor David Heymann: It’s too early yet to say the long-term effects of this, but certainly, like other viruses including, for example, the virus that causes mononucleosis, there is a period afterwards where people are still fatigued, still sick, and in Covid-19 it appears that there are many, many more symptoms that are occurring in these people.
Remember, this is an animal virus that had adapted itself to animals and now it’s in humans.
Counsel Inquiry: Right, okay.
Could you explain to us, please, the difference between asymptomatic transmission and asymptomatic infection.
Professor David Heymann: Asymptomatic infection is people who become infected with an organism and never show signs and symptoms. That’s asymptomatic infection.
Counsel Inquiry: So never any development of any signs –
Professor David Heymann: Never developed signs and symptoms from that virus.
Counsel Inquiry: Yes.
Professor David Heymann: Asymptomatic transmission is when a virus or bacterium, in this case a virus, when a virus is being shed by the person before onset of signs and symptoms, and that can then transmit to others. We know that occurs, for example, with measles, which is a respiratory infection, it occurs two to three days beforehand, and many virus infections are thought to transmit before the onset of signs and symptoms.
Counsel Inquiry: Right, so asymptomatic transmission is the transmission before any signs or symptoms, but after which the person may well develop signs and symptoms?
Professor David Heymann: That’s correct, yes.
Counsel Inquiry: Thank you.
Professor David Heymann: They will develop signs and symptoms.
Counsel Inquiry: They will.
Just to complete this part of your evidence, what then is pre-symptomatic transmission? Is that the same as asymptomatic transmission?
Professor David Heymann: I would say they’re the same, yes.
Counsel Inquiry: All right.
At paragraph 29 in your report, you say that:
“SARS-CoV-1 was transmitted primarily, but not exclusively, in health care and hospital settings …”
And that:
“The majority of [patients] were adults between 25-70 years of age.”
And that:
“The investigations did not identify groups at [greater] risk of serious outcomes after infection …”
Is that right?
Professor David Heymann: (Witness nods)
Counsel Inquiry: Why do you think there were so few suspected or confirmed cases of infection in children under the age of 15?
Professor David Heymann: As we understand this, it was transmitted in hospital settings by procedures such as cleaning out of the lungs, and therefore it was in adult patient care areas. The nurses who became infected or the health workers who became infected and transmitted it to others were transmitting it in adult patient wards, not in children’s wards.
Counsel Inquiry: With SARS, did infection provide immunity against reinfection?
Professor David Heymann: It’s not known, it’s not known. And there were too few cases to really study that.
Counsel Inquiry: So what factors led to its containment after the period of about six months, I think you said?
Professor David Heymann: Well, those factors I reviewed earlier, was the fact that it was very difficult to transmit from human to human, it required very close contact with droplet spread. The world worked together to limit travel to where outbreaks were occurring –
Counsel Inquiry: Yes.
Professor David Heymann: – and it didn’t get into countries where there was poor surveillance which might not have detected it, and permitted it to spread further.
Counsel Inquiry: That was the reference to Africa?
Professor David Heymann: That’s correct, yes.
Counsel Inquiry: So it didn’t become endemic in humans?
Professor David Heymann: It did not become endemic in –
Lady Hallett: Professor Heymann, sorry, going back to something you said just now, you said transmission was thought to be in hospital settings, so it was by treating adult patients that the hospital workers got infected, and then they were dealing with adult wards. But why weren’t the hospital workers then going home where there were children so children would get infected that way?
Professor David Heymann: They did go home and they did transmit it in the household, and some children were infected, but the majority of people who were infected were adults.
Ms Blackwell: When did the last known human infection occur, and how did it occur?
Professor David Heymann: The last known human infections of SARS Coronavirus 2 –
Counsel Inquiry: No, SARS Coronavirus 1.
Professor David Heymann: SARS Coronavirus 1, sorry. The last human infections of SARS Coronavirus 1 occurred in laboratory accidents: one in Singapore, one in Taiwan, and several outbreaks caused by laboratory accidents in China.
Counsel Inquiry: Right. Let’s move on to MERS, please.
First identified in the Kingdom of Saudi Arabia in June of 2012, humans became infected from close contact with camels, as we heard yesterday.
Was the route of transmission between the species through droplets or bodily secretions or faeces or the combination of all three?
Professor David Heymann: Between humans?
Counsel Inquiry: Yes.
Professor David Heymann: Yes, in MERS coronavirus there is transmission from person to person by body secretions or by droplets, or similar close contact. It occurs in hospital settings, called nosocomial infection, when health workers don’t practice washing of their hands or when they’re using equipment which has not been properly sterilised between patients. That’s the major means in which MERS coronavirus transmits from person-to-person.
Counsel Inquiry: How many cases were there in the United Kingdom?
Professor David Heymann: There have been five cases known in the United Kingdom, but three importations of the virus. So the virus was first imported in 2012.
Counsel Inquiry: Yes?
Professor David Heymann: Then since then there have been two other importations, and one of those importations was transmitted to a person who had accompanied the patient, and also to a visitor of the patient.
Counsel Inquiry: Right.
There was then a second major outbreak in the Republic of Korea in 2015, when an infected person returned home from the Middle East, so brought it from the Middle East, and became ill and was seen at various health facilities.
Professor David Heymann: Yes.
Counsel Inquiry: Is that right? Again, substandard infection control at those facilities which led to the infection there?
Professor David Heymann: That’s correct. There were many factors that were thought to have caused this to spread so rapidly. One of those was the fact that the patient went to three different health facilities, and the infection prevention and control measures in all of those facilities was substandard.
Counsel Inquiry: Were poor, yes. We’re going to come to that in a moment.
Professor David Heymann: Okay.
Counsel Inquiry: But in total, your report tells us that there were 185 cases in this outbreak, with 38 deaths, so that’s a case fatality rate of 20% or thereabouts, in the South Korea outbreak.
There were, you tell us in your report, a series of factors causing the infection to spread, and you’ve begun to tell us about that. There was weak hospital infection control, weak patient isolation procedures; is that right?
Professor David Heymann: Yes.
Counsel Inquiry: Leading to infection of other patients and family members. And also a nursing shortage. So that led to a dependence on private, less well trained caregivers; is that right?
Professor David Heymann: That’s correct.
Counsel Inquiry: Yes. And extremely crowded emergency departments without any isolation beds.
But it was rapidly contained, was it not, Professor Heymann, within a couple of months?
Professor David Heymann: That’s correct.
Counsel Inquiry: Was that containment down to a change in policies in the hospital setting and an improvement in the infection controls?
Professor David Heymann: That’s correct. There was an improvement in infection control after retraining of hospital staff. There was also an increase in ventilation in hospitals, which dried out those virus particles.
Counsel Inquiry: As we’ve already discussed?
Professor David Heymann: Yes.
Counsel Inquiry: Yes.
Professor David Heymann: And there was also an understanding by the population, because of good communication, what this virus was doing and how to prevent infection. So there was a major effort at communication, which is always important –
Counsel Inquiry: Right.
Professor David Heymann: – in outbreaks.
Counsel Inquiry: Does it follow from what you’ve just said that the main or the primary route of transmission of MERS was through droplets or aerosols –
Professor David Heymann: That’s correct.
Counsel Inquiry: – in the same way that we’ve described in SARS, with SARS?
Professor David Heymann: Yes.
proclaiming that masks don't work.
Counsel Inquiry: Were there any superspreading events in relation to MERS? And can you describe to us what a superspreading event is, please.
Professor David Heymann: Yes, there were superspreading events – in which virus, in MERS?
Counsel Inquiry: In MERS, yes.
Professor David Heymann: In MERS there have been some superspreading events. This was one in South Korea, for example.
Counsel Inquiry: Yes.
Professor David Heymann: And there have been events where there have been several different cases in hospitals where one person was admitted. But it’s been very patchwork, the understanding of this virus, because there hasn’t been clear and transparent sharing of information in many instances.
Counsel Inquiry: Right. What is a superspreading event, in scientific terms?
Professor David Heymann: A superspreading event is when a person who is infected for some reason or another is able to infect many, many other people. So it may be due to the fact that there are many people in a very small closed space and the person is able to transmit because he or she is at the right phase of transmission and then transmit.
Superspreading events are events that occur when the risk factors line up in such a way that they can occur.
Counsel Inquiry: All right. So what we have described happening in the hospital setting in South Korea, that would be described properly as a superspreading event, would it?
Professor David Heymann: That’s a superspreading event.
Counsel Inquiry: Even something on that fairly contained, small scale?
Professor David Heymann: Yes.
Counsel Inquiry: Was MERS capable of asymptomatic transmission?
Professor David Heymann: It’s not yet known whether asymptomatic transmission occurs among humans, but clearly it occurs from camels to humans. The disease is now endemic in camels. The virus is carried in the nasal passages and transmits quite easily to humans.
Counsel Inquiry: All right. So has it become endemic?
Professor David Heymann: It’s endemic in camels, yes.
Counsel Inquiry: Yes. But not in humans?
Professor David Heymann: Not in humans, no.
Counsel Inquiry: Right. All right, well, that brings us to Covid-19.
It’s no part of this Inquiry to debate or to determine the origin of Covid-19, but you attempt to assist us in your report by setting out what you consider to be the theories of origin.
Can you explain to us, please, Professor, what those consist of?
Professor David Heymann: There are two major theories about the emergence of this virus in human populations.
Counsel Inquiry: Yes.
Professor David Heymann: One is that it came from a bat into an intermediary animal, and from that animal into humans, possibly at a live animal market. That’s one hypothesis.
Counsel Inquiry: Right.
Professor David Heymann: The other is that there was a laboratory accident at a major, highly secure laboratory in Wuhan, and that laboratory we know was dealing with bats that had coronavirus, and that laboratory, the hypothesis is that either the virus was able to escape from studies that were going on in a human who left and was infected, or through some other means. The hypothesis then concludes in some instances – the other hypothesis is – that the virus was being manipulated in such a way that it gained function, it gained the possibility of transmitting easily between humans.
So these are all hypotheses.
What’s important from them is that there are messages that we can use. We need to make sure that live animal markets are conducted in the right way, that the animals that come to those markets are raised in conditions where they can’t become infected.
Counsel Inquiry: Right.
Professor David Heymann: And at the same time there need to be better standards of laboratories, high security laboratories, and those standards need to be developed by the people working with viruses, and adhered to by them.
Counsel Inquiry: All right. So between those hypotheses, you aren’t able to say which one is more likely or which one is more probable?
Professor David Heymann: I’m not able to say that, because I don’t have the evidence.
Counsel Inquiry: No. But they are both –
Professor David Heymann: They’re both hypotheses, yes.
Counsel Inquiry: Thank you.
In terms of the sequence of events at the start of the pandemic and the global spread, are you able to explain to us, Professor Heymann, how that happened in the immediate outbreak in China and how that travelled around the world?
Professor David Heymann: Well, there, again, are some hypotheses on this and some evidence from that, but it’s felt that it was possible that the province where this outbreak began was suppressing information about it, for some reason or another, and that when the central government did understand that it was going on they reported it to WHO. That’s one of the hypotheses. That’s what many people believe.
It doesn’t really matter now what happened back then, we have to deal with the virus as it is today, and WHO, when they received the report on 31 December in 2019, the next day did provide information about it, and then continued to provide information about the virus, through what’s called the International Health Regulations system.
Counsel Inquiry: Yes, we’ll come to that in a moment. Before we look at the advice that the World Health Organisation gave in the immediacy of the outbreak, I’d just like to return to something that you’ve now confirmed in relation to all three of these coronaviruses, so SARS, MERS and what we now know as Covid-19.
You’ve referred to what I’m going to describe as a lack of candour or a lack of information, a lack of willingness to share information on behalf of some countries.
Why is that such a problem?
Professor David Heymann: Well, when a country shares information about a disease, it often has economic repercussions.
Counsel Inquiry: Yes.
Professor David Heymann: For example, if a country says that they have cholera, then other countries may stop importing seafood from that country, tourists may stop going to that country, and so countries don’t like to report. So in discussions at WHO it was understood that because there is no international policing mechanism to force countries to report –
Counsel Inquiry: Yes?
Professor David Heymann: – the way to do it was to change the norm, so that countries understood it was expected and respected to report. That’s what the Director General of WHO did during the SARS outbreak in 2003.
Counsel Inquiry: How did he do that?
Professor David Heymann: She actually announced publicly, four months after the outbreak had begun, that China was not sharing information with WHO, and therefore WHO couldn’t do a full risk assessment of what was going on.
Counsel Inquiry: What happened? Did that have a repercussion or an effect?
Professor David Heymann: That had an immediate effect, in that the vice premier, Madam Wu Yi, immediately travelled to Geneva, apologised to the Director-General, began to share information in China, was able to stop the outbreak very – the outbreaks throughout China very rapidly.
So after that it’s become understood that it’s expected and respected, and most countries now continue to report, including China.
Counsel Inquiry: What about MERS, was the same procedure adopted in relation to the concerns about a lack of information sharing there?
Professor David Heymann: There was hesitancy of the government of Saudi Arabia to report at the start, and one of the doctors who had been treating the initial patient thought it was SARS Coronavirus 1, and he did a genetic sequence and put that sequence publicly, and fortunately it was in the public domain because that’s how the UK knew that they had a case imported.
Counsel Inquiry: Right.
More recently, then, with Covid-19, what concerns have been expressed internationally about a lack of information sharing from China in the early days?
Professor David Heymann: Yes, there was concern about a lack of sharing of information. I don’t want to take a position on that. WHO did receive information, did put it out to countries –
Counsel Inquiry: Yes.
Professor David Heymann: – and countries in Asia took that information very rapidly and acted upon it.
Counsel Inquiry: Right.
Professor David Heymann: These were countries that had had SARS previously and they were very attuned to coronaviruses.
Counsel Inquiry: All right. Well, we’ll return in a moment to deal with those countries and what perhaps could have been learned by their experiences, and why they were able to react so quickly to –
Professor David Heymann: Yes.
Counsel Inquiry: – Covid-19 when it started to spread.
But returning for a moment, please, to the initial outbreak, what reports and recommendations were provided internationally by the World Health Organisation about travel or travel restrictions?
Professor David Heymann: Well, WHO recommended in its first emergency – second emergency committee meeting after that, WHO took the recommendation of the emergency committee, which said that there should not be an interruption of travel and trade, especially for humanitarian purposes, if it was required to ship goods or other equipment to countries.
Counsel Inquiry: Do you understand and concur with that advice?
Professor David Heymann: In general, I do, yes. In fact, the best defence against the spread of international infections is good, strong national surveillance and detection mechanisms.
Counsel Inquiry: Right, and what do you mean by that?
Professor David Heymann: What I mean by that is that countries have surveillance systems which can detect unusual events very early –
Counsel Inquiry: Yes.
Professor David Heymann: – whether it’s reported from a community or reported from an emergency department or from the health system in general.
Counsel Inquiry: And that, in your opinion, is a better – the surveillance is a better method of controlling an initial outbreak or reacting to an initial outbreak than travel restrictions?
Professor David Heymann: Yes, because infections can travel asymptomatically in persons who don’t develop signs and symptoms until they’ve crossed that international border.
Counsel Inquiry: Yes.
Professor David Heymann: So it’s a false security to think that borders can stop infections.
Counsel Inquiry: In later modules to this Inquiry we will look at the advice which was issued for preventing the infection spreading throughout the United Kingdom, but laying the groundwork now in terms of mask wearing, if I may, at paragraph 83 of your report you confirm that the World Health Organisation on 29 January of 2020 recommended wearing a medical mask alone during home care and in healthcare settings in the community, that that offered adequate protection against transmission if combined with hand hygiene and other infection prevention and control measures, but that a medical mask was not required for individuals without respiratory symptoms in a community setting, and that there was no evidence at that time on its usefulness to protect non-sick persons?
Professor David Heymann: Yes, that was WHO’s recommendations.
Counsel Inquiry: Do you have any comment to make about that advice that was provided on 29 January?
Professor David Heymann: That was solid advice to prevent transmission in care settings, and it was very important, and medical masks have been recommended – were recommended for health workers.
Counsel Inquiry: But it wasn’t until much later, I think, in 2022, that the World Health Organisation unreservedly recommended mask wearing for the general public whenever there was a need to decrease community spread, but you would say, I presume, Professor, that by that time there was so much more evidence available?
Professor David Heymann: That’s right. And WHO doesn’t like to make recommendations without an evidence base. They don’t like to make precautionary recommendations, which are recommendations which would be modified as evidence comes in.
Counsel Inquiry: So would you agree with a description that the initial advice, back in January of 2020, displays a hesitancy of the World Health Organisation in advising that mask wearing was appropriate? Or is it your evidence, Professor, that in fact that was solid, taking into account the very limited amount of evidence that was present at that time?
Professor David Heymann: Yes, WHO has said that the reason they didn’t recommend earlier is because they didn’t have the evidence to make that recommendation.
Counsel Inquiry: All right. And as you’ve just said, the evidence base is extremely important –
Professor David Heymann: It’s very important, yes.
Counsel Inquiry: – for the World Health Organisation?
Professor David Heymann: But there can be precautionary measures that are made, recommendations that are made, which were not made by WHO at that time.
Counsel Inquiry: Even taking into account that Covid-19 is a fairly recent disease, are you aware of case studies in China around the asymptomatic transmission of the virus?
Professor David Heymann: There was a study early on about asymptomatic transmission in a household, but again the case definition was not clear what was being used and it was not really – it was published and it was peer reviewed early on, but it wasn’t really clear that this was an article to be followed. There were very few number of family members involved.
The evidence really came from Singapore, when they were able to look at seven different clusters of persons who were infected and were unable to link them to people who had clinical signs and symptoms.
Counsel Inquiry: Right.
Professor David Heymann: But people who they were able to link them to in context, some of them did later on develop signs and symptoms.
Counsel Inquiry: All right. You’ve mentioned again there the case definition. Are you able to help us, Professor, with how the case definition of Covid-19 may have altered over time based upon the increasing evidence?
Professor David Heymann: Yes. Early on the case definition in China, for example, was a case definition of a very serious illness which required hospitalisation.
Counsel Inquiry: Yes.
Professor David Heymann: So they only were finding those serious cases because that’s what they were looking for, when other cases were likely occurring as well.
Counsel Inquiry: Right.
Could I ask you to explain for us, please, the reproductive number.
Lady Hallett: Before you do, can I just pause. The transcript is not running. Are there any problems?
Ms Blackwell: I think mine is, my Lady.
Lady Hallett: Maybe it’s just me. I seem to have stopped rolling.
Sorry, forgive me, it was just me.
Ms Blackwell: Not at all.
I was asking you, Professor, about the reproductive number. Can you explain what it is and how it relates to Covid-19, please.
Professor David Heymann: The reproductive number is the number of people who become infected from a person who is able to transmit the virus or a bacterium.
Counsel Inquiry: Right.
Professor David Heymann: So if the reproductive number is 4, that means that one person can infect four other persons, provided there is no immunity among the persons to which that person is exposed.
Counsel Inquiry: Yes, all right.
In relation to Covid-19, has the reproductive number dropped over the course of time?
Professor David Heymann: Reproductive numbers drop as the number of people in a population become immune, either from vaccination or from disease. So the reproductive number has dropped in the UK, for example, it’s now thought to be less than 1 –
Counsel Inquiry: Yes.
Professor David Heymann: – which is what cannot sustain transmission.
Counsel Inquiry: Could we display, please, paragraphs 99 to 101 of Professor Heymann’s witness statement, his report, which is at INQ000195846_0021. Thank you.
I’m just going to read through this with you, Professor Heymann, dealing with the various symptoms of Covid-19.
“99. It is currently estimated that up to 33% of those infected in highly vaccinated populations do not develop recognisable signs and symptoms of infection after vaccination or on reinfection. Except for those with comorbidities, including obesity, the rest have a broad range of mild to severe signs and symptoms that can include a new and continuous cough, anosmia (loss of smell), ageusia (loss of taste), and a range of non-specific signs and symptoms including shortness of breath, fatigue, loss of appetite, myalgia (muscle ache), sore throat, headache, nasal congestion (stuffy nose), runny nose, diarrhoea, nausea and vomiting.)
“100. Decreased blood oxygen saturation is a hallmark of serious illness after infection with SARS-CoV-2 and complications including respiratory failure, acute respiratory distress syndrome (ARDS), sepsis and septic shock, thromboembolism, and/or multi-organ failure, including acute kidney injury and cardiac injury.”
If we can just move up, please, to complete this at paragraph 101:
“Infections in the elderly, and in others from derived areas, and/or from certain non-white ethnic backgrounds have caused more serious illness and death. Underlying health conditions such as diabetes and chronic renal disease, as well as obesity likewise increase the risk of severe disease and death in adults.”
Now, that collection of symptoms and effects were not known about on the immediate transmission back in December of 2019, so does that picture build over the course of time as the transmission increases and we are able to see a variance in terms of the case definition, and does that expand?
Professor David Heymann: Yes. This is called the natural history of infection.
Counsel Inquiry: Right.
Professor David Heymann: All the signs and symptoms that are associated at one point or another with infection. It does modify as more information is obtained and focus is not on persons who are seriously ill, but on persons who have a positive diagnosis but have less serious illness, and this often depends on being able to identify an infection by a laboratory test.
Counsel Inquiry: Right. Why is it, Professor, that symptoms may be more severe for those who have comorbidities, in particular obesity?
Professor David Heymann: In obesity it’s thought that there is a physical component to that, where – as it’s very difficult for an obese person to breathe at times, especially when there is a pulmonary infection, making it very difficult to exchange oxygen.
Counsel Inquiry: Right.
Professor David Heymann: At the same time, persons who are obese have a greater risk of diabetes too, and diabetes decreases the immune response to infections, it’s known that that occurs with bacterial infections and it also occurs with viral infections.
Counsel Inquiry: Right, thank you very much. We can take that off the screen now.
Just before we break – I’m conscious of the time, my Lady, and how long the stenographer has been working.
Lady Hallett: I was wondering that. There have been some difficult words to transcribe.
Ms Blackwell: Yes.
Lady Hallett: Is that a convenient moment now?
Ms Blackwell: Yes, it is.
Lady Hallett: Very well, I think we will probably take a break. I will return at 11.20.
Ms Blackwell: Thank you.
(11.06 am)
(A short break)
(11.20 am)
Ms Blackwell: Thank you, my Lady.
We were talking about the facets of Covid-19 and the various aspects of it that are important and that perhaps set it apart from other viruses.
I’d like to turn to ask you, please, about the incubation period. What do we know about that so far?
Professor David Heymann: Well, the incubation period is the period, as we talked earlier, from the time of infection to the time of onset of signs and symptoms.
Counsel Inquiry: Yes.
Professor David Heymann: It’s thought to be anywhere between two and 14 days, although it will become more precise as more analysis of information becomes available.
Counsel Inquiry: All right. How does that compare to, for instance, the incubation period of influenza?
Professor David Heymann: Influenza has a shorter incubation period, about one to three days or four days, so it’s a much shorter incubation period, and therefore the virus can increase much more rapidly in infecting people than can one with a longer incubation period.
Counsel Inquiry: Right. We’ve talked or touched upon herd immunity and you’ve explained to us what that is. Does the incubation period have any connection to herd immunity or how often – sorry, how quickly, how rapidly a population can become immune to a disease?
Professor David Heymann: Yes, in fact the more rapid – the shorter the incubation period, the more rapidly the virus can spread –
Counsel Inquiry: Yes.
Professor David Heymann: – and therefore cause an immune response in the people who are infected.
Counsel Inquiry: Thank you.
Moving on to deal with the current figures for deaths and cases from Covid-19, as of the end of May of this year, globally there were 767 million cases and close to 7 million deaths. Those are the official figures.
What is your opinion, Professor, about the danger of relying upon official figures and whether or not, in reality, those figures are likely to be considerably higher?
Professor David Heymann: Well, when reporting figures, it depends on many different things. The reporting of cases by countries, confirmed cases, depends on their testing strategy.
Counsel Inquiry: Right.
Professor David Heymann: So some countries have a much higher testing rate than other countries. Some countries didn’t bother doing testing at all. So the reporting of cases is usually based on confirmed cases, and that depends on the testing strategy. Other countries may report suspect cases; it may not be clear in those statistics who reported suspect cases, who reported confirmed cases, and, again, the confirmed cases depend on the laboratory strategy, so cases are not a good way of evaluating or at least comparing one country to another.
Deaths, however, are a much more solid figure, because deaths usually occur in a hospital setting in most countries, or many times do, and therefore it’s a better indication if it’s confirmed death of the number of cases that are occurring.
Counsel Inquiry: But even in relation to numbers of deaths, is there a difference between how some countries interpret a death caused by Covid-19?
Professor David Heymann: There is. In fact it depends on what’s on that death certificate in many countries, and sometimes there are comorbidities which have become the cause of death, but they were the cause of death because of a Covid infection, yet it’s reported as being a death from one of those comorbidities.
Counsel Inquiry: So The Economist has recently calculated excess deaths globally as being in the region of 22 million, and that’s a much higher figure, three-fold higher than the confirmed level of 7 million deaths globally.
Professor David Heymann: Yes, and those excess deaths would also include deaths of people who could not obtain healthcare for routine problems during a pandemic or the epidemic, and therefore added higher rates of mortality, causing more excess death.
Counsel Inquiry: Right, so excess deaths is not in itself an indication of deaths caused for certainty by Covid-19?
Professor David Heymann: No, that’s correct.
Counsel Inquiry: All right.
I’d like to ask you now some questions about the level of preparedness of Asian countries for Covid-19, those who had experience of SARS and MERS in their recent history.
What effect do you think having a serious outbreak of those two previous coronaviruses had on countries such as Singapore, Japan, South Korea, Taiwan and Hong Kong?
Professor David Heymann: I believe they had a profound effect on those countries. In fact I visited some of those countries during the period after SARS and before the current pandemic, and some of those countries had actually established isolation wards with hundreds of beds in their hospitals, ready for when there should be an outbreak such as this. So they were developing surge capacity in those countries at the same time as they were training their health workers in procedures such as contact tracing. So they appeared to be much better prepared, because of what they had learned from the SARS outbreaks back in 2003.
Counsel Inquiry: So you have mentioned two things there, surge capacity within hospitals, training of health workers in contact tracing. Why was that second element so important?
Professor David Heymann: That element was important because early in the outbreak countries such as Japan, for example, did not only contact tracing looking forward to see who was in contact with a person who was sick, but also looked backwards to try to find the source of infection, and when they found that, they then did what they called a precision lockdown: they locked down where the source of infection was. That’s good basic epidemiology and outbreak control.
They did this in countries such as Singapore, in South Korea, in Japan, in Taiwan and other places as well.
Counsel Inquiry: That was effective in controlling the spread?
Professor David Heymann: It certainly appears it was effective, yes. In fact, they were able to stop outbreaks that – there were major outbreaks in South Korea, there was a major outbreak around a church event, as there was in Singapore, and those outbreaks were completely contained and stopped, which permitted those countries to let the virus enter at a much lower rate because there were fewer people infected to infect community members.
Counsel Inquiry: But to be effective, a precision lockdown has to take place very quickly after knowledge has been gained that the virus is spreading?
Professor David Heymann: That’s correct, yes.
Counsel Inquiry: Before it gets out any further?
Professor David Heymann: That’s correct.
Counsel Inquiry: All right. Those countries who had the ability, because of the training of their healthcare workers, to undergo contact tracing and then to set up a precision lockdown, were more successful in continuing(sic) the early spread of Covid-19?
Professor David Heymann: It’s my view that they were, and if you look at the results of that today, you will see that their mortality rates are much, much lower than mortality rates – reported mortality rates in most European countries.
Counsel Inquiry: All right. Let’s take a look, please, at paragraphs 113 and 114 of your report.
(Pause)
Counsel Inquiry: 113 and 114, please. Next page. Thank you. If we could highlight those two paragraphs, please.
So just to confirm what you have told us, Professor:
“113. Early in the Covid-19 pandemic, studies in Japan traced contacts of persons with Covid-19 forward for isolation and monitoring, and backward to the source of infection. They then shut down those areas where transmission was shown to be occurring, many times in nightclubs, gyms and other public spaces, until preventative measures could be reinforced at those sites.
“114. Such precision and short-term lockdowns demonstrated that unlike influenza, initial Covid-19 outbreaks could be contained and transmission interrupted. The same was true in Singapore and South Korea in early outbreaks that occurred in religious institutions and nightclubs [which is what you’ve just told us]. Many Asian countries continued to keep transmission at low levels before vaccines became available by outbreak investigation and precision lockdowns at the source, similar to those used in Japan. [So] As of 19 February 2023 Asian countries had reported fewer Covid-19 deaths per million in the population …”
And you there give the figures:
“… (Japan 566, South Korea 680, Singapore 294; [which are to be] compared to Italy 3,150, USA 3,344 and the UK 3,038) [thereby] attesting to the effectiveness of their containment strategies, though other factors including the level of comorbidities and obesity may have also played a role.”
Thank you very much.
So those figures speak for themselves, really, do they not?
Professor David Heymann: Yes.
Counsel Inquiry: You have described, when giving evidence before today, what is known as a surgical lockdown. Is that the same as a precision lockdown, simply a different way of expressing the same?
Professor David Heymann: That’s correct.
Counsel Inquiry: All right.
What is your opinion of the knowledge that the United Kingdom could and perhaps should have had of the effect that SARS and MERS had had in those Asian countries and how that knowledge could or should have been used in its pandemic planning?
Professor David Heymann: In pandemic planning, the UK was very strong in influenza.
Counsel Inquiry: Yes.
Professor David Heymann: That was what their planning was mainly about. Because, in fact, that was on the top of their – the risk register in the UK. So there was very much emphasis placed on influenza, and preparedness activities were going on.
As we’ll talk about possibly later on, preparedness, though, doesn’t just include strong public health, which is mainly the focus of many of their preparedness plans. It also includes a surge capacity, the resilience of a health system to be able to take care of patients who are infected, as well as patients who have routine health issues, and in addition healthy populations are better to resist serious illness after infection, and health populations include those with fewer comorbidities.
Counsel Inquiry: Right. So just taking us back for a moment to the evidence that you’ve just given about the preparedness of those Asian countries who had had a severe experience of SARS and MERS, is there anything about the lack of information sharing that you’ve also told us about that may have affected the United Kingdom having the ability to find out and understand the way in which those diseases had affected those countries?
Professor David Heymann: I think the information was pretty well available, it wasn’t available yet in peer reviewed publications, because it takes time to get those out, but it was being exchanged within WHO, within circles around the world, and I think most informal contacts of health systems in countries understood that this was quite a serious outbreak in Asia, especially after the Diamond cruise ship event, where a person from Hong Kong is thought to have infected passengers on a cruise ship.
Counsel Inquiry: Right, so does the fact that the United Kingdom didn’t have surge capacity, it didn’t have hospitals with ventilators and beds awaiting a virus such as this, and didn’t have a contact tracing system set up, indicate that we hadn’t learnt from the previous experience of those Asian countries with SARS and MERS?
Professor David Heymann: The UK had quite a good case – contact tracing systems. In fact they’re used at the local level regularly for outbreaks that occur. But they occur at the local level, where trust is very important, because if people are going to give information about their contacts, they’re going to give it to people who they trust. So countries including the United Kingdom centralised more their contact tracing activities, and by so doing there was less of a trust in that contact tracing, and it may be that it was less effective.
So the lesson that I think we’ve all learned, and I think many of us knew before, is that contact tracing must be done where there’s trust, and where you can interact with people. It can’t be done digitally in an effective manner.
Counsel Inquiry: All right. What about the lack of surge capacity?
Professor David Heymann: The lack of surge capacity, after the influenza pandemic there was an increase in hospital respirators, as far as I understand, and there had been practice in activities related to influenza, but they were just not activities that were with the current pandemic, and I’m not sure whether or not – I can’t say whether or not they included what might happen if capacity in hospitals was overwhelmed, although the UK responded rapidly with its units that they did set up.
Counsel Inquiry: All right.
Finally before we leave this topic, please could we display the report of Exercise Alice, which is at INQ000022732, please, and go to page 16.
Exercise Alice, as you will know, Professor, was an exercise, a tabletop exercise that was delivered on 15 February of 2016 involving the Department of Health as it then was, NHS England and Public Health England, and it was based around a large-scale outbreak of MERS, and dealt with two stages: first of all the initial actions of the local health organisations and, secondly, a position when the virus had spread to a wider number of cases.
What we can see here, at page 16 of the report, at appendix A, is the summary of lessons and actions identified. I’d like to highlight, please, if we could, number 5, action number 5. Thank you. We can see that recommended by those producing the report was a briefing paper to be produced on the South Korea outbreak of MERS, “with details on the cases and response”, and to “consider the direct application to the UK including port of entry screening”.
First of all, do you consider that that was an appropriate lesson to learn and action to raise?
Professor David Heymann: Yes.
Counsel Inquiry: Do you know, Professor Heymann, whether or not that briefing paper was ever prepared?
Professor David Heymann: I do not know.
Counsel Inquiry: All right. Thank you very much, we can put that away, please.
Predicting future pandemics. This is something that we touched upon yesterday in the evidence of Professor Whitworth and Dr Hammer, and they described to us the phenomenon known as Disease X and why it’s important for countries to expect the unexpected or to look forwards and include in our pandemic planning a disease which is not yet known about, the details of which are not known about.
Do you agree with that?
Professor David Heymann: Yes.
Counsel Inquiry: Can you explain to us why you think it’s important for that to be part of a country’s pandemic planning?
Professor David Heymann: If you look at a Disease X as being a respiratory infection or a respiratory disease, and look at the various outcomes of what might occur from that respiratory infection, then you can begin to prepare based on different scenarios. It’s not just one scenario. As we talked earlier, it may be a respiratory virus that produces deep in the lungs, it may be one that produces superficially. But it’s usually – Disease X, in my view, is respiratory infection, but there are other means of disease spread, as you know.
Counsel Inquiry: Yes.
Professor David Heymann: It can spread by enteric infection, infections from food or water, and they can spread by vector-borne – mosquitoes and other insects. So there are many different ways in which infections can be spread. But Disease X to me is that rapid spread of an infection, usually a respiratory infection.
Counsel Inquiry: What Professor Whitworth told us yesterday was that, in his opinion, it’s important to have a generic plan in place that can be adapted depending on the specific details of the disease that becomes a pandemic, that attacks us, if you like. Do you agree with that?
Professor David Heymann: Yes, as long as it can be adapted based on the different characteristics of known – what we know about viruses, where they reproduce, how rapidly they transmit, incubation periods and a whole series of other issues.
Counsel Inquiry: Do you think that a pandemic on the scale and severity of Covid-19 could have been predicted?
Professor David Heymann: I don’t believe it could have been predicted precisely, no. I believe that there was concern about coronaviruses, that they could spread rapidly within populations. We had endemic coronaviruses. So I think there was concern about it, but an outbreak such as this cannot be precisely predicted because you can’t predict an outbreak based on only one thing, and that would be a virus; it has to be those risk factors that line up to cause the emergence and to cause the infection to spread.
Counsel Inquiry: The Human Animal Infections and Risk Surveillance group known as HAIRS, tell us, please, Professor, what that group works on and the importance of the work that it does in terms of the animal kingdom, diseases there, zoonosis, and the prediction of what might be coming along the line.
Professor David Heymann: The HAIRS group is a One Health group, and One Health means that the animal, human and environmental sectors are working together on risk assessment, risk analysis and risk management.
It’s a very important mechanism within the UK, the UK was one of the first countries to develop such a mechanism, so it’s very important, and in addition it includes the devolved administrations and it includes Ireland, the Republic of Ireland. So it’s a very important way of looking, doing horizon scanning, looking – what infections are occurring in animals and what their risk might be to human populations.
The HAIRS group meets – it’s the environmental sector, the government sector, the human health sector and the environmental sector – meets once a month, and they look at what’s on the horizon, and they see whether or not that can be considered as a risk in the UK, and if the UK’s not prepared they recommend guidelines, they recommend doing things to become better prepared.
So it’s a very useful mechanism, and hopefully what it could do is shift the paradigm from rapid detection and response to prevention at the source, by knowing the source of where these infections might come from. It’s a very important concept, because today most countries think: well, what we need is a rapid detection system, then we’ll rapidly respond. What is needed is a One Health environment where hopefully, in the future, epidemics and pandemics can be prevented.
I can give an example.
Counsel Inquiry: Yes, please.
Professor David Heymann: In MERS coronavirus, we know that it’s endemic in camels.
Counsel Inquiry: Yes.
Professor David Heymann: We know that humans get inspected sporadically from time to time from camels. The obvious solution to this is to develop a vaccine and use it in camels. As long as that prevents infection of camels and prevents nasal carriage of the virus, we can prevent future outbreaks of MERS coronavirus. That’s why it’s important to be looking at both the animal and human sector and the environmental sector at the same time.
Counsel Inquiry: So prevention at source, meaning the animal before the zoonosis occurs, before the disease jumps into humans, rather than the rapid detection and response once that has happened?
Professor David Heymann: Both are important, but it’s – certainly the ideal is to shift the paradigm back to prevention at the source.
Counsel Inquiry: Yes, thank you.
Let’s then, please, move to your conclusions and recommendations. May we look first, please, at recommendation 1, which is at page 55 in your report.
Each of your recommendations is preceded by a conclusion, and in relation to recommendation 1 you have concluded that research needs to be cutting-edge, the UK needs to maintain its high vaccination rate.
And if we can go to the next paragraph, please, paragraph 262, we can see here your first recommendation is this:
“Funding for research should continue in order to answer questions related to the pandemic strategy adopted by the UK, including total population lockdowns, and the impact the strategy has had on sickness and death, and on surge capacity and resilience to continue routine healthcare. Funding should also be made available for analysis of long-term outcomes including better understanding of long Covid and other sequelae, and for better understanding of the impact on pandemic control measures on mental health, on youth, and on industry and business in the travel sector. By joining the Horizon research programme of the EU, in which the UK was a leader in the past, increased funding would become available to supplement that provided nationally.”
So that is what you are recommending in relation to continued funding?
Professor David Heymann: That’s correct. The UK in fact has contributed much, much information to the literature because of their excellent research capacity and because of the funding that was made available by UKRI on the rolling call for research that could be completed within a period of 12 months early on in the pandemic. In fact, I chaired the panel that reviewed those research proposals. They were excellent and they gave very important information.
Counsel Inquiry: Thank you.
Can we move to paragraph 264, please, which is recommendation 2. Thank you.
Before this you have said in your second conclusion that the United Kingdom is one of the most respected donors of international activities to better prepare the world for epidemics and pandemics. So your recommendation here is that:
“Funding should continue to be made available to national academic and technical experts so that they are able to support international activities that strengthen epidemic and pandemic preparedness and response activities, including support for funds at academic institutions and within government that permit replacement of skills nationally when UK experts are responding to overseas needs. Official development assistance (ODA) support should also continue to be provided both to public-private and other pandemic preparedness activities, as well as to international organisations that provide global guidance and support epidemic and pandemic prevention, preparedness and response capacity development. This should include continued active participation of the UK Government in negotiations around the revised International Health Regulations and the pandemic treaty, using its soft diplomatic power when needed.”
Do you stand by that recommendation?
Professor David Heymann: I stand by that recommendation.
Counsel Inquiry: Thank you.
Moving to paragraph 266, please.
Recommendation 3, at 266, is to:
“Continue to make permanent cross-government interaction in activities that lead to stronger epidemic prevention, preparedness and response, and identify means of including the private sector in such activities by ensuring that conflict of interest – whether perceived or real – is understood and respected in decision-making.”
If we could move to paragraph 268 and deal with these together, your fourth recommendation is:
“Cross-government working in a One Health mode [which you’ve described to us a moment ago] – without ceding to the temptation to create a separate One Health Ministry or agency – should be formalised and permanent. Cross-government work in a One Health mode for epidemic prevention, preparedness and response should continue, and include all economic sectors, both public and private, so that a shift can be made to prevention at the source. Such a shift might be partially accomplished, for example, by increased use of cost-effective vaccines in humans and animals, cleaner agriculture, and cross sector joint risk assessment, analysis and action.”
Taking those two recommendations together, you are very much of the view, Professor, are you not, that not only should there be cross-government work but also what you’ve described as One Health work within both the government and the public and the private sector, without being tempted to create a One Health Ministry or agency, because that would be effectively working in a silo and what you are promoting is working very much as a whole?
Professor David Heymann: Yes, in fact during the pandemic I had the opportunity to see what many different companies in the UK were doing as their preventative measures to respond, and also with the airline industry, because they contacted me, having worked with them during the SARS epidemics in 2003, and it was clear that they had many innovations which might have been useful within the government, had the government included them in some of their discussions, and I think there was quite a high level of frustration that they had to work separately from the government because of this fear of a perceived conflict of interest.
Counsel Inquiry: Yes.
Professor David Heymann: So it’s always there, that concern for conflict of interest and it’s very important, but I think there are ways that lessons can be learned from the private sector, from others, that can be useful in government and vice versa.
Counsel Inquiry: Joined-up thinking?
Professor David Heymann: Joined-up thinking. Not only across government but across sectors.
Counsel Inquiry: Thank you.
Finally, recommendation 5 at paragraph 270 – you recognise in your fifth conclusion that:
“Some of the failures in epidemic and pandemic preparedness could have been prevented by focusing on preparedness activities that include, but are not limited to, the public health system.”
You there mention again surge capacity within the NHS.
So your recommendation 5 is to:
“Increase [the] DHSC oversight of the partnership between the government agencies responsible for health improvement, medical management and health protection/public health with a focus on better epidemic and pandemic preparedness in the future.”
Professor David Heymann: Yes.
Ms Blackwell: Thank you very much.
My Lady, please could you grant permission for Professor Heymann’s report to be published?
Lady Hallett: Certainly.
Ms Blackwell: I’m just being given some instructions from behind.
Lady Hallett: While you read those instructions …
When you spoke about HAIRS – we have a lot of these acronyms – who established it? Is it a government-type organisation, is it a voluntary organisation amongst experts? How is it operated?
Professor David Heymann: It’s an organisation among experts, my Lady, and it was established by the Health Protection Agency back in the early 2000s as a means of bringing together technical people within the government and within the devolved administrations and the Republic of Ireland.
Lady Hallett: Thank you.
Ms Blackwell: My Lady, before I finish, I’m being invited to ask two follow-up questions on advice in relation to the wearing of masks, and I’m happy so to do with your permission.
Professor Heymann, can you explain why the experience of SARS and MERS, both being coronaviruses, may not have been sufficient evidence for the World Health Organisation to have advised at the beginning of the Covid-19 outbreak that mask wearing was a good precautionary element to take?
Professor David Heymann: Well, it’s very difficult to set up a study to determine the effectiveness of mask wearing, and there was great confusion in the general public, and in fact in some governments, about what mask wearing was for.
Wearing a mask was to prevent others from becoming infected, unless that mask also included protective covering of the eyes. So mask wearing was a means of preventing transmission to others from a person who was infected.
It’s very difficult to set up a study to evaluate that and collect evidence, because it’s hard to know who’s infected. So the evidence was not there and these outbreaks were relatively small, MERS coronavirus and SARS coronavirus, and there weren’t studies that were set up to evaluate that.
In Asia, masks have been worn as a courtesy when people are infected for many, many years, and when a person has an upper respiratory infection many times they wear a mask to protect others. So it was much easier for them to implement activities of mask wearing because the population was accustomed to it.
Counsel Inquiry: Would there have been any downside to the World Health Organisation as a precaution, once Covid-19 was beginning to spread, advising that masks should be worn?
Professor David Heymann: There would have been one downside and that is the fact that medical masks were in very short supply, and if the general public were trying to get these masks as well as the health community, it might cause a very serious problem. So I know in the US, after an outbreak of a choir in March of 2020, they recommended cloth :outline:`face coverings. to prevent transmission from a person infected to others. So there was concern, I believe, in many circles, including at WHO, that by making a recommendation to wear masks, this would compound the shortage which was occurring of medical masks.
Ms Blackwell: Right, thank you very much. That’s very clear.
My Lady, I have now finished. As my Lady knows, we have a procedure in place during which core participants are able to warn us of questions or areas of questions that they wish to ask, and I know that Allison Munroe King’s Counsel, representing the Covid-19 Bereaved Families for Justice for today’s purposes, wishes to ask one question based around a topic which we have been informed about.
So, my Lady, you have provisionally given an indication that you would provide your permission for that to be done. May that now be done?
Lady Hallett: Thank you. Yes.
Ms Munroe.
Ms Munroe: Thank you very much, my Lady.
Questions From Ms Munroe KC
Ms Munroe: Thank you.
We’re now at the afternoon – oh, it’s still morning, just. Good morning, Professor Heymann. My name is Allison Monroe, and I represent the Bereaved Families for Justice UK.
Just one topic, and one question and one point of clarification arising out of that topic, which I’d like to ask you and seek your assistance on, please.
The topic is the issue of infectious disease strategy, and by way of a sort of point of clarification, in a general sense, when one thinks about or plans a strategy for infectious diseases, there would be a raft of different components, some more important than others, within such a strategy, wouldn’t there?
Professor David Heymann: Yes.
Ms Munroe KC: This is not an exhaustive list at all, but, by way of example, some of those components would be things such as good public health, and a good public health system, clear consistent messaging, high levels of co-ordination, intra-governmentally and with the scientific community, with health communities, early alertness of infectious diseases, and a clear understanding of where transmission happens and an effective way of rapidly stopping that and shutting that down; would you agree?
Professor David Heymann: Yes.
Ms Munroe KC: Those are some of the more important components. Thank you.
Within that context, then, Professor, the question arises from something that is said by somebody that I think you’re probably very well acquainted with, Professor Dame Jenny Harries, who will in due course be giving evidence to this Inquiry but has provided a written statement and a number of exhibits.
My Lady, I don’t propose to take Professor Heymann to any particular documents, but, simply for the purposes of reference, the part of Dame Jenny Harries’ documents that I wish to refer to are found at INQ000090317, and it’s an exhibit, JH/M10009.
Now, she refers in that part of her statement, Professor, to a document, quite an old one, from 2002 called Getting Ahead of the Curve. You’re nodding there. A document you’re probably very familiar with?
Professor David Heymann: (Witness nods)
Ms Munroe KC: For those who are not, by way of a very, very abridged summary, it effectively was produced by the then Chief Medical Officer, Sir Liam Donaldson, and it recognised that the country faced a number of public health challenges, including infectious diseases, and it looked at ways of dealing with that, and it recognised the need to bring together skills and expertise of a number of separate organisations to work in a co-ordinated way.
Going back, then, to the question that is posed, Dame Jenny Harries says this in her statement – it’s at paragraph 106, for reference, my Lady:
“In 2018, on a UK national level, Public Health England identified that there had been a gap in national strategy across governments focusing on infectious diseases, and this gap had been apparent since 2002 and the Getting Ahead of the Curve document. Having recognised this gap, work was then started in 2018 to address that issue of a strategy for infectious diseases, and it was published in the autumn of 2019, identifying ten different strategies including a strategy for infectious diseases.”
Now, I appreciate, Professor Heymann, that you’re not a person who makes policy decisions or policies, but are you able to assist us at all in terms of why there was that gap of a period of some 17 years, 16 years, where there was no detailed infectious disease strategy?
Professor David Heymann: I really can’t answer that question. It’s my understanding that there were several plans on infectious disease prevention and control which were developed. I don’t know what she’s referring to that was the gap. I don’t know – I would need to see what documents were prepared, and I can’t answer your question, I’m sorry.
Ms Munroe: I’m very grateful.
My Lady, that’s the question on that.
Lady Hallett: Thank you very much, Ms Munroe.
Right. Now, I think one of the next witnesses is attending via videolink.
Ms Blackwell: Yes, we need to rise very briefly, please, my Lady.
Lady Hallett: Thank you very much indeed, Professor Heymann. Not only were you very helpful, but you were very clear too. So thank you.
Professor Heymann: Thank you very much.
(The witness withdrew)
Lady Hallett: Let me know when you’re ready.
Ms Blackwell: Thank you.
(12.04 pm)
(A short break)
(12.10 pm)
Lady Hallett: Mr Keith.
Mr Keith: My Lady, may I please call Professor David Alexander and Bruce Mann. Professor Alexander is joining us from abroad by videolink.
Lady Hallett: Professor Alexander, I understand you have recently undergone a bereavement, I’m very sorry.
Professor Alexander: Thank you very much. I also had cardiac problems, so I do apologise most profusely for not being present in person.
Lady Hallett: Totally understand, thank you very much.
Mr Keith: Could they therefore be sworn, Professor Alexander obviously remotely.