COVID-19 analysis

Expert view: Dr. David Heymann on how COVID-19 will reshape our world

As part of our continuing service to update the travel retail community on COVID-19 and its impact on business, The Moodie Davitt Report last month hosted a follow-up phone-in audience with public health expert Dr. David Heymann. This came after his similarly well-attended interactive discussion with the travel retail community in early February.

The Moodie Davitt Report Chairman and Founder Martin Moodie and President Dermot Davitt hosted the session with Dr. Heymann, covering the current global response to the coronavirus, the search for a treatment and a vaccine, and what lies ahead for a changed business world when the outbreak passes. An edited transcript of the briefing is presented here.

Photo by Tedward Quinn on Unsplash

Click below to hear an edited summary of the discussion with Dr. David Heymann

Martin Moodie (MM): Dr. Heymann, could you give us an update on the situation as it stands globally?

Dr. David Heymann (DH): I'll start with China. All of you know China has had quite a bit of success in decreasing the transmission of this virus in the epicentre and has also stopped many outbreaks outside the epicentre. They continue to try to interrupt transmission of this virus completely.

They are beginning to lift some of their lockdown procedures and are getting some people back to work very cautiously, while the rest of the world watches to see what happens. The concern is there might be a second wave coming out of China, especially as their air traffic increases. It may be that this spreads further internationally. But at present China is having more cases that come in every day from Europe and other parts of the world than are actually occurring in China, based on what they understand about their epidemic. They have been very free with sharing their information with the World Health Organization (WHO) since they first reported the outbreak.

Dr. David Heymann

In the rest of Asia – in Singapore, Hong Kong and South Korea for example – they have had quite good success in decreasing the transmission of the virus. In places like Singapore, where I was two weeks ago to do some teaching, they have continued very much with business as usual and with schools open. They are watching very closely to see what happens. So far they have not been able to trace any cases back to someone who was at school, so they feel that school opening possibly hasn’t caused any impact on the outbreak yet, but they are watching very cautiously. They recently stopped travel coming into Singapore from other places. Business continues more or less as usual with temperature-taking of everyone as they enter a public space, such as a restaurant or government building.

Singapore has been the most liberal in how they have approached this, having learned a lot from the SARS outbreak, but they are being very cautious. That reproductive number, which has been below the limit of one – which means one person infected from each person that has infection – is seeing a gradual increase towards that level.

South Korea has done a remarkable job in containing the major outbreaks that occurred mainly from two church gatherings. They have been able to decrease the number of new cases and have also been able to prevent high levels of mortality, as has Singapore, partly because they were prepared. They have each had coronavirus outbreaks in the past, so they are gradually gauging this virus, but they are gradually seeing an increase in its transmissibility in the community so they are anticipating it will continue to circulate.

The same is more or less true for Hong Kong. They see cases come from Mainland China; they immediately identify and isolate. Testing is very important because you can isolate people as soon as you find they are infected, so you decrease new cases of transmission.

“When this is over, there will be a changed world. People will have developed ways of working that they never used before and some of those will increase in importance, like more getting together virtually.”

Photo by Mika Baumeister on Unsplash

In the Middle East, the major source of infection has been a pilgrimage site in Iran and that has then spread out to many countries. Those countries are taking very draconian measures. There are two different populations they are working with: one is the local, national population and the other is guest workers, who are often in cramped conditions in dormitories and they are trying to make sure there isn’t an introduction of the virus into those places as well. That is their strategy in the Middle East and the jury is still out as to what is happening in Iran at this point.

Looking into Europe, you have seen what happens in a country where there is no preparedness or weak preparedness and not enough hospital beds and ventilators, as has occurred in Italy and now in Spain. There are extremely high levels of mortality; this is due to an ageing population, as well as a lack of hospital beds and ventilators for patients that are sick.

In the rest of Europe, they are seeing an increase in cases after initial efforts to contain the outbreak. Various strategies are being developed in different countries based on the national risk assessment and the capacities in those countries to do such things as testing, isolation and putting patients on ventilators. Most of the strategies in Europe are now to flatten the curve to make sure that their hospital system isn’t overwhelmed. There are new ventures being undertaken, such as in the UK where the NHS has worked with the private sector to increase the number of public beds and ventilators available.

North America has varied responses depending on the states in the US. There are several states, like New York and California, that have taken measures very similar to what has been going on in parts of Europe with keeping people indoors. It is still too early in the US to see what is going to happen there.

Canada has chosen a different strategy. They had SARS outbreaks and are dealing with this in a quite different way. They haven’t yet shut down everything, but they are instilling in their people what needs to be instilled in people everywhere: the understanding that they have the capacity to control this outbreak themselves if they self-isolate. The other strategy is to protect yourself by social or physical distancing: shutting down cinemas and events and at the same time self-isolating. People are anticipating these measures will at least flatten the curve, but the disease will not disappear.

Some people have hoped the disease will disappear in the summer months. This is certainly possible because other respiratory infections do decrease in the summer months. The flu season has a finite ending at this time of year in the Northern Hemisphere. Mucus membranes, which are where this virus lives, are drier in the winter months, which makes easier infection than summer months when mucus membranes are more moist. Those are characteristics that will perhaps impact on transmissibility.

Photo by Brian McGowan on Unsplash

Some studies are going on to look at the virus to understand if it has characteristics that will not permit it to spread in warm summer months, but as we all know it has been very healthily transmitted in parts of Asia like Singapore and Hong Kong, where springtime is occurring, so it is not clear the virus has any particular characteristics that would make it less transmissible in the summer months.

The virus can live on surfaces in droplets. In some studies, it has been shown it can live up to 72 hours on plastic surfaces. So surfaces, where people are infected, are very important to keep washed down and clean of virus.

MM: How concerned are you about that second wave and, leading on from that, how effective are travel restrictions at containing this virus?

DH: The WHO has changed its view to letting governments do their own risk assessments and make their own recommendations based on them. The world has changed since the regulations that govern international travel and trade and outbreaks were developed back in 1969, and then modified in 2005. Now there’s an incredible amount of information that’s available, both informally through discussion groups on the internet and also from published information in medical journals which have been peer-reviewed. This permits countries to have access to all kinds of information that they didn’t at one time have access to.

There have been several meetings. Every other day there is a meeting of the advisory group that I chair trying to look at such issues, as well as issues as to how a country can best begin to unlock its severe precautionary measures of travel, industrial production and social gatherings.

There is a virtual meeting today [held on 24 March – Ed] in Geneva where there will be experts from countries that have had success in outbreak containment and countries where they are not having such success. Then the advisory group will work with the WHO secretariat to look and see what some of the measures might be that countries should begin to think about as they unlock. Those will be of course based on national risk assessments.

I am not sure where travel will fit into that, but the travel industry has been severely affected. There are ways the travel industry can think about how they can begin to make their industry more safe. Some of them are radical measures and I'm not saying they are useful, but they might provide the public with more certainty. For example, if there is a cruise coming up, everyone must have a test to see if they have had an infection in the past or present.

Antibody studies that can tell if somebody had an infection in the past are now coming on the market, but many of them have not been validated. That means we know they work against some people who have antibodies that have recovered, but they also may interact with antibodies from other coronaviruses, so they need to be validated to see if they are specific to this coronavirus or not. If they are, it would be easy to see people that have had an infection in the past three months and they could be in a different category to those that are still susceptible. There are all kinds of things coming on the market that may help in the innovation of the travel industry as they think about how they want to proceed.

Photo by Kelly Sikkema on Unsplash

MM: I guess the same principle for the cruise sector could apply to the airline sector. A safety or health clearance certificate would have to be carried by any passenger before they fly. Is that possible?

DH: It may be possible, but it may not be effective. That’s the problem because people can travel while they’re still in the incubation period. If they haven’t had both an antibody test and an antigen test — which is the test that tells you whether or not you’re infected at the time — they could be carrying the virus onboard. They might even be coughing and not have reported it and so these measures are a false security.

Taking the temperature at a restaurant in Singapore or before you get into your university class may offer a feeling of security, but may not be entirely secure. It does eliminate people who have a fever and haven’t taken medicine to decrease that fever. It eliminates them from the classroom or the flight, but it’s not a scientifically valid way of stopping the spread of a virus or preventing infection. It’s more of a population reassurance method.

MM: Can Europe, the US and other areas with the virus cases surging now replicate the containment measures in Asia? When can we expect the new case numbers to slow in these areas? If so, in what kind of timeline?

DH: The general public can see how their neighbours and fellow citizens are behaving. If people are not following the warnings and keeping a physical distance, and the country is not closing down public spaces, then there will be a lack of assurance that the recommendations are being taken to heart.

People must be at the heart of this by understanding how to prevent themselves from being infected, and also preventing others from getting infected by them should they be sick. If the public begins to see that everybody understands this and begins to change the way they live, then they can be assured that at least the public is trying to do its job by decreasing transmission by distancing from one another.

To be able to say for sure what is happening can only come from the figures. Italy is now at a point where figures are one day on the increase and one day on the decrease. So the general trend in Italy is that they have flattened the curve now and are pulling out of a very terrible situation, which came mainly because they didn't have the hospital beds and they have an elderly population.

As you said, each country has to make its own judgement. As a general population, you can begin to see if people continue to keep their distance and do what is recommended then things can change rapidly.

MM: Will strict restrictions such as those imposed in the UK be effective if people follow the government guidelines, and can it bring the situation down rapidly?

DH: Hopefully it can, and that’s what these governments are banking on, but remember this is new territory. We’ve only seen a clampdown, as is occurring in Europe now, in China. And China was successful in decreasing the transmission. The number of people known to be infected there is quite small based on the total population. The question is now what will happen with all these non-immune people in China, just as in Europe.

A good indicator of whether or not effectiveness can be obtained is watching the people of a country not being aggressive toward others or not taking justice into their own hands. The key is trying to help everybody understand how important it is to protect the elderly, and those people who live in the same households as the elderly, or work with them, because there may not be support for them if they do get sick and the hospitals are overcrowded.

From all that we can see, the transmission is still occurring and we don’t know if it’s at the same level as it was a month ago, or whether it will be at the same level next month. And we don’t know if it will disappear in the summer months but then come back again in the autumn. These are questions nobody can answer at this point in time.

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MM: When you meet with your fellow health experts and the WHO, how much of the dialogue is around the other toll of this – the economic toll? Do you talk about both aspects and how best can the health and business community work together?

DH: There are a lot of models showing the cost-benefit of intervening and identifying patients and isolating them, as opposed to letting an outbreak continue and having a high mortality rate with the elderly population in hospitals.

In general, countries don't put a price on saving a life, so saving lives is the bottom line in all countries and at present, they are willing to spend what money they must in order to save lives, which is the way we have been oriented in our societies and is the oath all medical professionals take. There are cost-benefit analyses, but these really aren't valid in making decisions.

The way industries can work best is by working with governments through the World Economic Forum and other groups to try to understand where there might be less risk in certain sectors that could begin to open up in the next two to three weeks, when governments will try to reassess their policies of asking people to stay at home. If industry can feed into that reassessment, it is very important. The problem isn’t just people whose salaries are shut down, but those that don’t have enough to live from month to month in countries across the world. Being cut off from income is going to cause great inequality and a great problem for many countries.

MM: Millions of people die each year from influenza, but we haven't in recent history reacted the same way we have to COVID-19. Is that primarily because of the unknown nature of this strain?

DH: The unknown is what’s really been the problem. We are designing new ways to deal with this virus because we don’t know if number one, whether this will continue to transmit long term, and number two, whether it will become endemic like seasonal influenza, which also comes from the animal kingdom into humans.

There are now three human influenza viruses, which have found humans to be a suitable population to inhabit, and they continue to circulate year-round but in epidemic form. By that I mean in the Northern Hemisphere and the Southern Hemisphere particularly in the winter months. So, these are previous emergent, and these are emergents that have now gone on.

The unknown has been complicated by the modellers who have been trying to make estimates based on mortality and other issues that we know about, which are really not completely understood. So originally, you will remember that the mortality was thought to be very high in China. It was high there because they were looking only at seriously ill cases and making their case fatality ratios based only on all severe cases. Now, the case fatality ratio is decreasing, and it will decrease in various situations in various countries depending on the support they can offer patients.

So modellers have seized on different figures (it’s like the elephant and the blind man, one looks at the tail, one looks at the head) and are confusing things by putting out various models that are meant for public health use that are extrapolated to the general population by the press causing great concern.

At the same time, we don’t really understand the reproductive number of this virus. It was thought to be about two, which means that for every infection, two people could be infected in the community. But now, it’s decreasing in some areas based on the density of the population and other factors, and it seems to be increasing in others.

So many of the modellers take the highest figure and provide an estimate based on that high figure, which causes great concern. But really, this figure is only for public health planning, so that they can prepare for the worst case scenario. It’s not exactly a definition of what the worst case might be in a country. So, all these figures are floating around, and people get confused. It’s best to look at what the national risk assessment is saying and what countries are doing because that’s where they understand the figures that go into the epidemiological models in more detail.

MM: Moving on to the critical question of a vaccine. What is the situation with and likely timeline on any vaccine? Can the increasing economic urgency hasten the process and how effective could a vaccine be?

DH: Vaccine development is being done right now by the small biotechs. They will want to go through animal studies, as required by regulatory agencies, in an animal model that can be infected and reacts the same as humans. The good news is they have identified such a model: the macaque monkey can be infected and does develop illness within six days or so. That means there is an animal model. As vaccine candidates are developed, they will go into safety and effectiveness studies in animals. If they are shown to be safe and effective with animals, they will go into human studies and then studies of humans looking at their capacity and ability to provide antibody protection. Finally, efficacy studies would show whether or not they are effective.

The process normally takes at least a year for vaccine candidates such as this and then the regulatory agencies will look at all the dossiers that come from various studies and make a judgement on whether a vaccine is licensed.

Once a vaccine is licensed, there then has to be production capacity identified. That has to be by the major pharmaceutical companies that are willing to divert their production lines from routine vaccines to produce the vaccine in quantities enough so that countries in the world can have access.

What is happening now is the processes that would usually be linear are already going on in parallel, so there is already a search for what companies might be able to produce a vaccine in many parts of the world. Once that is identified, there will have to be cleaning of production lines with the vaccine put into production. Many countries have laws that no vaccine can be exported until national demand has been met. So all those issues are a problem in making sure there is access worldwide to a vaccine.

It is not as easy as it may seem to get an effective vaccine. Some companies are not using the virus, but synthetically-produced particles that look like parts of the virus, which will work as a vaccine. They are shortcutting the animal trials and going direct into human trials. This is a new way that companies are working and even if they do have some vaccine candidates, they do then have to go into the process of identifying a production partner.

To summarise, if there is a vaccine that is shown to be effective, it would likely be available by early next year. Having said that, nobody is really clear how long immunity can last after that person has an infection. The question is then if the vaccine would be effective in one dose or if it would need more than one dose. Those are all questions that will need to be answered in the future.

There is a lot of work going on in drug development, which is being done against viruses we know, to see how they react against this virus that we didn't know previously. If there is a useful anti-viral, it will have to be used early in infection because using it after someone is already moribund or on a ventilator will not have any impact. It has to be used very early.

Certain institutions are collecting plasma from people that have been infected and recovered to study the antibody, and attempt to use it to either prevent infection or serious illness in those that have been in contact or are identified early on as infected.

There is a remarkable amount of information going on both for drugs and vaccine but nothing has yet shown those to be effective.

Photo by Tedward Quinn on Unsplash

MM: Looking to the uncertain future with this immense global and economic impact in ours and all business sectors: once this is dealt with in whichever way, is it going to happen again? How can we minimise the risk of further virus outbreaks and learn from this global experience?

DH: When this is over, there will be a changed world. People will have developed ways of working that they never used before and some of those will increase in importance, like more getting together virtually. I am doing Zoom conferences with many people every day. These normally would have been face-to-face meetings and we are seeing now that you can cut down on those and still have effective outcomes while not disrupting daily agendas.

It may be that in the future there is less travel for face-to-face meetings. This will have an impact on the travel industry and airlines, especially those that have survived this severe blow.

It’s the same with the cruise ship industry. There will need to be some confidence-building measures to ensure passengers will not end up in a situation as has been seen.

This will be based on innovation. Humans are very innovative and there will be innovations that work in this changed world to instil confidence in passengers. These are things for the industries to think about now as they move ahead, understanding that it will be a changing world and what we had counted on for incomes in the past may not be so sure in the future. I hate to paint a gloomy picture, but that is the reality as I see it.

MM: Do you think there is any merit in a global lockdown and if so how, or who is best to enforce it? Does the WHO need greater powers? Should it be more demanding of global leaders and less advisory in its approach?

DH: The United Nations system, including the WHO, was set up after war, or during a period when there was great uncertainty in the world. It provides a great place to get people together and to provide technical guidance to countries but it has no police enforcement power. So its recommendations remain recommendations. Countries have not been willing to give up their sovereignty to the UN system, and I don’t know whether that could occur in the future or not.

I’ve been thinking through this issue with many colleagues and academia. An initiative such as this is better coming from the private sector, which is the one that’s the most effective. They need to be working closer together either through the World Economic Forum or through their industry groupings to better define what they would recommend. They could be the leaders on this because governments don’t make recommendations sometimes because of industry resistance in many ways. The industry is knocking on one door and public health on the other door and it makes it very difficult for governments to make decisions, and so they make them one way or another and get criticised – and remember these are elected officials.

So if industry were to band together, and to make its recommendations, understanding the public health and collaborating with the public health community, and to make recommendations about how they might see a lockdown, that might go a long way to promoting this type of an approach. But I don’t think the UN system, including the WHO, has the power or mandate to do that at present. My own view, having been with the WHO on a secondment from the Centers for Disease Control and Prevention (CDC) in Atlanta for many years, is that the WHO would not be able to have that power or take that authority. So it has to come from the private sector working with the public health community.

Photo by Anton on Unsplash

Dermot Davitt (DD): You mentioned the areas of vaccine and drug testing. The medical authorities in China have said the Avigan drug used in Japan to treat new strains of influenza has appeared to be effective in coronavirus patients. Do you think this could be an efficient solution for curing COVID-19?

DH: There are a whole series of drugs that are being studied. There are some that are used for the HIV infection virus, and some that are used for other viruses, such as the Lassa fever virus and even the Ebola virus. They are being studied first through laboratory testing and then in humans. China has gone into human research trials much more rapidly than many other countries, which are influenced by different types of regulatory agencies.

The information from China, as I understand it, is now being looked at by WHO and others in research groups. They’re looking at what has shown to be promising, but nothing can really be shown to be effective in this area, outside of rigorous case control studies and comparative studies, to people who receive the drug and people at the same stage and infection who don’t receive the drug, to see what the impact of that is. Or a comparative trial of one drug that is thought to be effective, against another drug that is thought to be effective. These trials have been done in China, but they don’t have the numbers of people enrolled in those trials to really give this the statistical validity that people would like to see before they make any recommendations on any drugs.

I think within the next two weeks, some initial results will be released that will give an idea of what might be useful. Those studies are going on, WHO is organising some of them, individual research groups are doing others, and there should be results coming out very soon. However, the problem is that these drugs have to be used early in infection. What many countries are seeing is not those people in early infection, but those that are overwhelming the health system because they’re already in acute respiratory distress. Those people who are requiring ventilation will not probably have a chance of survival with any anti-viral and possibly even those who are less seriously ill. So yes, there are promising drugs, but none has been successfully used in a study that has the statistical power to say that they are effective in treating this infection.

Photo by H Shaw on Unsplash

DD: A related question on a vaccine. We read a lot about the similarity between COVID-19 with SARS and MERS. Does any of the research conducted on those coronaviruses help speed up the development of a vaccine at all?

DH: Hopefully that will speed up the development and there’s a group based in London called the Coalition for Epidemic Preparedness Innovations (CEPI) which is keeping track of all those various vaccine trials that are going on and is funding many of the biotechs on the MERS and SARS coronavirus vaccines. Development was stopped after the outbreak but there is some work on MERS vaccines and those research groups are looking at how they can work more rapidly with the current coronavirus.

DD: Beyond Italy, other countries in Europe have ageing populations. What do you think will happen there? For example, why do you think the number of fatalities compared to infections is so low in Germany?

DH: Remember that the number of infections is only determined by the amount of testing that’s being done, and each country is using different testing strategies. Some are only testing people who are admitted to hospitals, others are testing people who have been identified as contacts. So, the number of identified persons is not a real indicator of the seriousness of the infection in a country. What is important though, is those people who get to the hospital and survive.

Germany hasn’t saturated its capacity yet to deal with these patients. It has a reserve capacity and the ventilators that it needs, and it has been able to support many people who in Italy would not have been supported because there was not hospital space. So, one of the keys to survival and mortality is the number of ventilators, the number of beds that are available, and the number of people who were identified early on with infection, who can be managed in a way that will prevent them from infecting others. So, the testing itself or the number of cases itself per country, is only an indicator of how much testing is going on. Because when you begin to test, you find cases. So, the cases that are identified more in Germany than in the UK for example, may be because Germany is testing more people than the UK.

DD: Finally, do you think these outbreaks will be something we see more commonly in our world and something we should price in as businesses?

DH: We hope industries will get together and take the warning from this. Not many groups took the warning after the SARS outbreak and, as a result, nobody is really prepared for this outbreak. The countries that had SARS were prepared and developed the extra beds and ventilators, but many others and industry did not heed the warning. In fact, they stopped investment in goods that could have been useful should SARS have reoccurred.

Now we are seeing new opportunity and hopefully, after this is over, those opportunities and innovations will be used to develop new ways of facing a world where we are at risk of infection spreading very rapidly.

It is important to remember that every infection in humans originated in the animal kingdom. In the past, they were able to circulate in a local or national population before spreading internationally. AIDS, for example, started emerging in the human population at the start of the 20th century, yet it didn't spread internationally until it got into a capital city, where there are risk behaviours that amplified transmission. Then it hopped on aeroplanes and silently spread around the world.

These things have occurred in the past and they will continue occurring in the future. We now need to think of new ways of dealing with them, including more involvement from the private sector with their involvement in contingency planning.

MM: Thank you Dr Heymann for an honest and helpful, albeit deeply sobering perspective, for which we are very grateful. We are also immensely grateful to you and all your colleagues right across the medical and health sector: from the level you and all your colleagues are operating at globally to the front line nurses and doctors around the world, who are helping the world cope with this terrible illness. On behalf of all of us, thank you for all you are doing and for your time today.

DH: Thank you Martin. We all have a role to play and I think we are all doing that.

Dr. David Heymann is Professor of Infectious Disease Epidemiology at the London School of Hygiene & Tropical Medicine and Head of the Centre on Global Health Security at Chatham House, London.

From 2012 to March 2017, Dr Heymann was chairman of Public Health England. Earlier in his distinguished career, he was Executive Director of the Communicable Diseases Cluster, and crucially, he headed the global response to SARS in 2003.

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The Moodie Davitt eZine

Issue 278 | 7 April 2020

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