WHO’s Fisher: "If the lockdown works, we will extend it”

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Interviewed By TAB RadioFinance

With countries shutting down their borders, many people ask whether or not lockdowns work. We invited WHO’s Dr. Dale Fisher to answer this question as well as address pressing concerns regarding the pandemic.

Are lockdowns effective in containing COVID-19? To answer that question, we invited Dr. Dale Fisher, chair of the World Health Organisation’s Global Outbreak Alert and Response Network. On 7 April 2020, Dr. Fisher spoke to Emmanuel Daniel and answered timely questions about the pandemic and the measures being taken to combat it.

The conversation’s main points were:

  • Natural herd immunity is not advised, as it would mean millions of infections
  • Global leadership is not possible as countries experience and deal with outbreaks in different contexts
  • The result of the lockdown is another lockdown to prevent a second wave
  • The main cure that the WHO is working towards is a vaccine; the interim relief and treatment don't really count

Here is the full transcript of the session:

Emmanuel Daniel (ED): Welcome to yet another session of RadioFinance. I’m pleased to have with us Professor Dale Fisher, the chair of the Global Outbreak Alert and Response Network (GOARN), an agency organised by the World Health Organisation (WHO), for Asia Pacific. He is a career scientist and a medical doctor in public health. He was also a member of the WHO-China joint mission that visited Wuhan.

Right now, we have a total of 1.3 million people affected by the coronavirus disease (COVID-19) with 74,000 deaths worldwide. In the US alone, there are 374,000 infected with 10,000 deaths.

There are different ways to measure this. We’ve all been looking at the bell curve chart, thinking that as long as countries get through that bell curve, they will be able to survive the process. That has been the logic behind the lockdown concept. There’s the idea that early detection, mass testing, contact tracing and a lockdown all contribute to taking the pressure off the medical healthy system in the absence of any form of remedy for COVID-19.

More than 125 countries have imposed lockdowns, which caused tremendous work suspension and business disruptions around the world. The whole idea of a lockdown playbook, is it a statistical welfare or an epidemiological (virus) welfare?

Dale Fisher (DF): There are plenty of military analogies flying around. A traditional outbreak response – whatever it is, cholera, ebola or a foodborne outbreak – it's ‘find the cases, early case detection, diagnose, isolate appropriately, find the contacts, track the contacts and if they get disease, then you can isolate them quickly’. Eventually, if you keep isolating the cases, you can shut down the virus because you're stopping it from spreading to other people.

That's where you've obviously heard the term reproductive number. If one person infects others, then obviously the outbreak keeps growing. If every person infects less than one other person or ten only infect five for instance, then the outbreak starts to shut down. Now, there is really no playbook which says lockdown. I don't think this has happened in modern history where cities, towns or countries have had to lock down.

ED: The idea of a lockdown, is that a Chinese invention?

DF: The process I described before was, you get a transmission chain, someone infects others, others infect others and then you try to contain that by blocking the next lot of transmissions. The contacts, if they're already in isolation, then they're not going to spread it on.

You stop the transmission chain. If you can't do that, and suddenly you got cases everywhere, contacts everywhere, you just have to start doing this massive thing called a lockdown, which I think China maybe did invent in January. This is telling people to go home, no work, no fun, no entertainment, you go to your house and you only come out if you absolutely have to.

This shifts the transmission into households. You get the household clusters, but eventually it burns itself out. If one household hasn't had contact with another household, even though the former had some cases, the latter stays clean. If you do that for maybe four to six weeks, then you will bring down transmission. That's what you're seeing in several countries now, such as in Italy and Australia. These cases come out.

ED: You say to bring down transmissions or is it to slow down transmissions? Is it inevitable that this particular strain of virus is going to be endemic rather than pandemic that's going to be at the baseline of human society going forward?

DF: Yes, it'll end up endemic. The end game is that the best that countries can do is try and contain it to as low as possible, because if you don't contain it, it kills tens of thousands of people and overwhelms your health systems. We have to do whatever we can to contain it.

ED: What do we know about the antibodies, for example, that if you get infected, are you therefore immune as a result that you actually build the antibodies? Do we know enough about that at the moment?

DF: I would not be advocating for natural herd immunity. It will come, but it needs to come through a vaccine because there's just too much devastation if everyone has to get naturally infected. Sixty percent of the world or millions of people need to get the disease, which means tens of thousands per day sort of thing. That'll be the case for a year or more. If there's a vaccine, that will cover most of the community. Vaccines are 100% effective, anyway. The disease won't go away, and not everyone will have the vaccine.

ED: With the lockdown period, are we talking ‘let's try one month, and then if it is still proliferating very quickly, we try three months’? What are we seeing now for the countries that had lockdowns for sufficiently long periods?

DF: There are three things that can happen during a lockdown. One is, you reduce transmission. Two is, when there's less cases, the hospital system can recover. Instead of having full beds and all your ventilators taken up, that will clear out. Either people will get better or they'll die. The first one, the transmissions should take four to six weeks. The second one is the hospital recovery, and that is going to probably take a little bit longer, maybe 8, 10 to 12 weeks.

But the hardest one for many countries will be, ‘how do you reopen?’ You need to have all those traditional things in place. There's only a small number of countries in the world, for instance, that actually isolate their positive cases. Most people send all these people home, and that's been a huge drive of the transmission because it's secreted even after you've recovered. Even though you got a young person in their 20s that's had a mild cold, firstly, he's going to have a lot of trouble staying home. Secondly, even when he's better, he's probably still shedding virus, but he's told he can go out. This is a major flaw.

How much contact tracing you can do? What sort of quarantine facilities you got? What sort of public health laws do you have in place to make sure these are brought in? This will actually take longer. In the United States (US) and Europe, they don't have these systems in place. Like in China, Singapore, Korea, Taiwan and Hong Kong, we all have these systems in place. This is why a lockdown in Singapore really could be four weeks.

My gut feeling is, if it's going well, they'll say let's have another four weeks, but it's much easier to open up in Singapore. It'll just be slow as well. It won't be suddenly everything's open, but they may be able to start undoing the screws quite quickly, because our hospital system is not overwhelmed and our systems are in place. All we need to do is stop the transmission chains. It's the other countries that will do a lot more work during the lockdown.

ED: How influential is the agency that you head, the Global Outbreak Alert and Response Network? How influential is it in countries like the UK, which seemed to favour the herd immunity type of approach? You seem to suggest that herd immunity is not the way to go. Some of the Western countries are discovering that as the numbers come in.

Yet, testing is not something that they're even able to do extensively, and those who are against testing are even complaining about the fact that you need to do multiple testing in order to actually know that the numbers are working out. Is there a coordinated global response or are different countries taking their own responses and hoping that a certain methodology would evolve from there?

DF: Normally, when there's an outbreak, the GOARN will be called on by a member state saying we got all these yellow fever, we got all these cholera or we got all these ebola. We can help support the country's response and we can send in some experts. During the West African outbreak, we sent in about 11,000 or 12,000 people during the course of that outbreak. But, of course, it's much more difficult dealing with a total pandemic, because for instance, I can't go and help in Africa now because I'm required here. Anyone that works for a national body has to really do their work at home. That's the first thing.

The other thing is, the narrative was stolen quite early by politicians, I'm afraid to say. You can think of all the countries, and these are not outbreak specialists, and often the chief medical officer are not infectious disease people.

ED: But at what cost? You just said that if Singapore finds that a one-month lockdown is working, then another one month for precaution’s sake will be good. But that's two months, and the impact on the economy will be a price that not many countries want to pay. In fact, if it extends for a little even longer than that, say three months, many countries will start to kick the barn door. People want to get on with their lives.

The good thing about the Singapore response is that they have tried to keep everyday life as normal as possible. We didn't go into DORSCO (Disease Outbreak Response System Condition) RED entirely. There is still social movement of sorts. China did a complete lockdown of Wuhan. New York is practically in a complete lockdown right now. The question is, how long, at what price and for what effectiveness?

DF: The mainstay is what I said about case detection, testing and isolating quarantine. After that, the only dial you got is the social limitations. You can wrap those up, and tell everyone, ‘You are locked in your house and you can come out once a week to go shopping’. That could be the extreme. Or you could say, ‘We are just going to close the nightclubs, the discos and the movie theatres because they're quite risky’. In between is where you got your dial.

This week, Singapore dialed up a little bit because we got a couple of big clusters, and we just want to bring things back under control. China, dialed it right up to the top, and you could say it's because they're a huge country of 1.4 billion, so it is easier just to make a blanket rule.

You might find in Europe and the US that everything is a little bit different, depending on what stage of the outbreak they are, in what they regard as essential and what the community can tolerate. The community can tolerate a lot more now than they could two months ago in terms of freedom and privacy.

ED: The one thing that is uniting everybody is the pressure the whole thing is putting on the health care system and the emergency centres, in any country. Let's walk through three or four key items. You were in the WHO team that visited Wuhan. What did you see there? What were they learning as the pandemic was evolving? What lessons did you take out from the Wuhan meetings that you attended?

DF: I wasn’t actually in Wuhan. I was on the mission, but only three of the members went to Wuhan. I went to Beijing, Chengdu and then Guangzhou, and we all met up at the end. We started together, and then we ended up together to write the report and share all our ideas. I don't think there is anything in that report that has been shown to be wrong.

We knew this could be devastating because we saw the devastation in China. There is actually a sentence in there that says, ‘This is going to have massive health, social and economic impact, and we don't think the world has the capacity or the mindset to deal with it’. We had a very negative approach, and sadly, we're being found to be correct.

I was just shocked seeing China in complete shutdown. Beijing with clear blue skies, no one on the streets and only a couple of cars. You look around at the high rises and you knew they were just full of people trying to entertain themselves for the month that they are in lockdown.

ED: In the report, you said that the so-called crude fatalityrate was 17% when the pandemic started or rather when the whole thing started building up, and then it was brought down to 0.7%. What was the cause of that large mortality rate? And what brought it down very quickly to that manageable number?

DF: When all you're doing is identifying the very sick people and the dying people, and you're not recognising all the mild disease, then your denominator is underestimated. That’s the first thing. The other thing is when your hospital is overwhelmed, you can't look after people properly.

Italy's running at 10% or 11%, but that's largely because they stopped testing the mild ones. The hospitals are overwhelmed, and they're just telling people, ‘Sorry, we're out of ventilators, so good luck with your oxygen masks’. The case fatality rate should be less than 1% when things are going well, but when you get overwhelmed, and you can see how easily that can happen, the death rate goes up.

ED: In a period that is overwhelmed, what other hygiene issues, infrastructure issues that can ameliorate problem to take some pressure off?

DF: Now, you just run out of stuff: beds, ventilators and personal protective equipment (PPE). You run out of energy, then you start to get healthcare worker infections and the people are just so tired and start making mistakes. Everything goes wrong, and then it goes wrong for non-COVID problems, as well. You can't look after your heart attack or your trauma.

ED: I have a question here from one of the viewers. Given that most of Europe has highly diffused infections, doesn't contact tracing have to start with testing the entire population? In other words, a lockdown timetable means testing everybody or everyone, as much as possible.

DF: It wouldn't really help, because you can be negative today and positive tomorrow. It would only give you a snapshot at that particular point in time. Once you've lost control, like what they have in Europe, then it's really just everyone staying in their houses. If you got a severe disease, come out then we'll look after you. But otherwise, you just let it burn out in the houses.

ED: Hasn't the WHO also been on a learning curve? At first, the messages that you've been putting out was, ‘You don't really need to wear a mask. If you need to wear it, wear it correctly, and then now it's wear it if you can’. The second is, how contagious is the disease and can asymptomatic people spread it just as virally? These are messages that you've been developing in the course of building your overall message, and even reverting back to things that you've said before.

DF: Firstly, of course, we're learning. The presymptomatic, shedding virus before you actually have symptoms, that has been proven to be true recently. I'm not sure asymptomatic spreads, but presumably, it's possible. There are people who never get symptoms. We know people who don't get symptoms, and they're asymptomatic throughout but positive on throat swabs.

The whole mask thing is quite contentious. In science, we don't believe, most of us, in public wearing of masks. I would much rather say, ‘Distance or don't go out’. If you're a metre or two from someone that has the disease, then you won't get it anyway. If you're keeping your distance and you're washing your hands so that anything you touch doesn't get into your mouth, then that's safe. But if you got any symptoms, then certainly wear a mask and cover it up.

I know Singapore and WHO have both said, ‘Look, you can wear a mask’, but they're not suggesting in any way that that's really what's driving the outbreak or the outbreak response. I personally think it's more to please people who feel strongly about it.

ED: The common sense appears to be: wear a mask. People are taking it into their own hands to develop their own idea of what the response should be in the absence of clear guidance, and in fact guidance that seems to be shifting from time to time. This learning process and what is an established body of knowledge in infectious disease, you've been there since SARS, I'm sure you've seen H1N1 and you've seen Ebola, a very good case study in terms of how the whole idea of creating immobility help to localise the infection rate, and then eventually highly localise it. In a number of these previous infections, there was no cure coming out of it. There was no vaccine coming out at the end of it. We are still dealing with an endemic scenario. Eventually, a lot of people will get some of these infections and we just need to keep it contained.

DF: All I can say is what the science tells you. We think it can be managed with people that are sick wearing a mask and healthcare workers wearing a mask. Or, if you're looking after someone sick, wear a mask because you got that continuous close contact. But, none of us believe that this is floating through the air and it’s going to get you if you're not wearing a mask. It can spread from presymptomatic people that you're having close and prolonged contact with, and that's what we're saying. Don't have close and prolonged contact with people, except, of course, your household because you're with them all the time.

ED: In the absence of a vaccine, the testing has to be perfect. The testing has to be much cheaper, more available and faster. Some of that is coming through. When do you think widespread testing and easy testing will become universal?

DF: There are a few tests being developed. The antibody tests are coming, but they're not going to be good for diagnosing disease. They'll be good for diagnosing recent or past disease. If you want to know if you've been exposed in the last three months, you could have an antibody test. To diagnose it now, there’s the PCR (polymerase chain reaction) test, with about a six-hour turnaround. That's because there are a few processes along the way.

There are definitely tests being developed, where that can all be done in like 45 minutes through an automated, but still PCR test. They're also trying for some antigen-based tests, which hopefully will be rapidly in point of care. The most important thing is that they're very sensitive and ideally specific. You don't want people to walk away with a false negative too often.

ED: Therefore, is herd immunity a misstep?

DF: The only way herd immunity could work is if the antibody tests find massive asymptomatic transmission. If you need clinical disease to be antibody positive, then herd immunity is not going to be a thing.

We know a lot of children are going to be antibody positive because they don't get symptoms. We know they're getting exposed and they get an asymptomatic disease. There's going to be some asymptomatic spread like that. But if you think of it, if the US is 250 million, and let's say 250,000 have so far been infected, then that's like 0.1%. To get to herd immunity, you need 60%. 

If only the clinical cases are becoming immune, then you can see the devastation you need if you're going to get to herd immunity by natural exposure. If we find that maybe it’s ten times that number because of all these asymptomatic transmissions, you're still only at 1%, and you got to get to 60%. 

The antibody studies are going to be important, but I honestly don't believe there's going to be so much transmission that natural herd immunity is a good thing. It's still going to come down to a vaccine or a good treatment. If a treatment stops people from dying, then that's fine.

ED: Let me go into one area, which probably has never been asked before, the whole governance model of the relationship between the foundations, the pharmaceuticals and the agencies such as yours, the Global Outbreak Alert and Response Network. Who funds your agency? Is it just countries or is it also large businesses?

Also, one of the criticisms of donor foundations like the Bill & Melinda Gates Foundation is that how much of that is donation and how much of that is investment in pharmaceuticals. There's another dimension of criticism coming through, saying that there is a kind of a covert agenda to get the whole world vaccinated because that's good for big pharmaceuticals. Where are you on that conversation?

DF: It wouldn't be businesses. It's donors. These are sometimes countries, sometimes organisations. There's no private or for profit business involved. The criticisms don't impact us at all. We wouldn't take money from pharmaceuticals. WHO has to be very squeaky clean on all this, obviously.

ED: Coming back on the numbers, again. We don't have a global, uniform data that we're looking at. When the US says that it got so many dead, that's different from what the Italians say and what the Chinese say. You have countries that are promoting herd immunity, and you don't even know what the numbers are in that country. It's very difficult to come up with a well understood global response, as well.

DF: My colleagues and I are in the outbreak business every day. We all believe that herd immunity is just madness, the governments that have gone for that. I've spoken to science, outbreak epidemiology people, and they have said, ‘I cannot convince my government that this is mad’. England actually did a backflip within a couple of days when they said herd immunity.

There are different types of governance.The relationship between the leaders and the experts is pretty wanting in most countries. I don't see Centre for Disease Control (CDC) standing next to Trump at the moment. If people have been watching, that man stopped appearing a couple of weeks ago. Clearly, the advice is not being heeded. They've moved on. 

ED: The US CDC has been found one thing in itself. When they put up its first test kits, they had to withdraw them because they weren't working. The Chinese version from the Chinese Centre for Disease Control seems to have worked a lot more coherently and had the authority to make the decisions that they did. Which countries do you think got the equivalent of CDCs that work as they should? What should be in place for CDCs to be able to function as they should?

DF: It's a good question. Across the world, it's very messy. Who's in charge, the national level or the state and provincial level? Most countries haven't really gotten it sorted out. In Australia, there are a lot of tensions. Some people have gotten powers for some things and then the national power for something else. But then, I've heard in Germany they think it was this devolution of public health response to the states, which was part of the strength because those people really have good relationships with their community. What should it be? I don't think there's one model that suits all. It depends on your system of politics. It's different in the Middle East, as well.

ED: Taking the lockdown playbook, what are the parameters that you have in place? What are the indicators that you have in place that you like to look at to see how it will play out? The rest of the society doesn't have the rest of the year to be locked down. There will be alternative responses coming up very shortly and there will be segments in the society that will say, ‘That's the price that we're going to pay for this’. Then, we'll just get on.

If you remember H1N1, the literature seemed to suggest that 250,000 people died. Singapore has about 13,000 Dengue cases every year. The idea is to reduce the mortality. There are mechanisms by which infectious disease can exist in society and be dealt with.

So, what are you looking at in terms of this particular COVID-19 lockdowns? When it works, what happens? When it doesn't work, what's the next thing that you need to do?

DF: As I’ve mentioned earlier, there's the lockdown, which is we've completely lost control, shut down everything. Then there is the traditional public health response, which was going okay in Singapore until we've had these couple of outbreaks that involve a lot of people in the dormitories and things that I think are pretty publicly known. 

ED: It happens. It is likely to happen in China as well.

DF: It's a question of how to come out of lockdown. You can, but it's going to be easier for some countries than others. It's a long time before we get 50,000 people in a football match again. By and large businesses and constructions can get back. There will always be some limitations, but it needs to be supported by this capacity to isolate the positive cases, which most countries still don't even have.

ED: I seem to get from this that the professionals in infectious disease are proposing lockdowns or anything that reduces mobility in order to be able to slow down the process of infection, but that may not well be the final answer as it were. We do not actually have a foolproof working model. You've obviously learned a lot from SARS, from H1N1 and from ebola, but we're now looking at an infectious rate that transcends all of them. Would it be that people in your profession should be saying, ‘Actually, we don't know how this is going to play out, we're making it up as we go’?

DF: No. We know a lot. We know that if we don't try and contain it, then the death rate is really high. We know that if we don't do everything we can, then it's very infectious. We also know we can contain it with lockdown, but obviously we don't want to lock down. That's why Singapore is trying not to lock down, and I do believe that in the next month or two, things will come easy again.

Australia's levels are improving again with a sort of a semi-lockdown. They got big open spaces, but Singapore is dense, so everyone's going to be a little bit different. 

ED: Would it make a big difference if a country like the US took the leadership, use your agency or some platform and created a coordinated approach towards a lockdown so that we can see where the movements are? China fears a transmission from outside of China, so the lockdown is now domestic. They don't want to let people into the country. In that way, different countries will have to have different responses depending on where they are in the transmission cycle. There should be leadership much stronger than what you have right now.

DF: Every country has its own sovereign rights. WHO can't go to UK or somewhere and say, ‘You're doing this wrong’, or go to Iran, China or anywhere. WHO got no power. Every member state of the world has its own authority to do it. We make recommendations, we offer help and we share experiences, but we can't do it. Even the experts within the country often have problems getting the message through to the leaders. I would love a world that you live in, where everything we want gets done.

ED: That world has arrived. We do need a global response. That seemed to be the only thing that we should be working towards, because what you're suggesting is, in the absence of a vaccine, there is no end to this.

DF: That's what I feel, unless the antibody tests show something that we're not expecting.

ED: Thank you very much for spending time with us. The sense I get is that we're all learning as we go along. The data is not uniform, the responses are not uniform, the disciplines are not uniform and there are a lot of conspiracy theories forming out on the sidelines, asking to be dealt with. It does look like there should be a more coordinated global response and authority, and the people who have that authority are not asserting them. 

DF: The only people with authority are the leaders of every sovereign state and there's no one else. There's no world body with authority. They might have influence, but that's the most. A coordinated global response knows that this is different in every city, in every country. Every city in the US got a different kind of outbreak. Australia's outbreak is different to Singapore's, which is different to Vietnam's, China's, Iran’s and Italy’s. Everyone's got a different population density, different population number and different mindset as to what they're prepared to take.

If you don't have trust in your government, the people also aren't going to respond very well. It's chaotic. There are many reasons it’s chaotic. There really is no one except the sovereign leaders that can say, ‘This is what we're doing in our area, I have a strategy. I've worked with my experts. I've spoken to people in other countries about their experiences, and here's our strategy for our state or our province’. These places will do better, but if you got someone that insists on something that makes no sense, then they’re the ones that don't do as well.

ED: You are stating a case for a new frontier that we don't yet understand. If you said exactly this at the beginning of World War I, you would be probably right. The Austrian Empire was different from the British, and the Americans are not interested in all of that. But, eventually, by the time we reached World War II, we had a United Nations and we had a global body, which shared ideas in terms of how to respond to conflict.

This now is a new dimension in conflict that we've never seen before. You are the technician who sits at the frontier of it, and as the days go on, we are going to find that there will be no way to respond to this unless we are far more coordinated than we are today.

It's been a revealing conversation. You did let through just now that if the lockdown in Singapore works for one month, it will be a good idea to have it for a second month, which coming from an infectious disease specialist is very interesting. It  reveals how you think about the effectiveness of these lockdowns and the eventual goals that you want to meet.

At the same time, you did say that the real goal that you're looking forward to is a final vaccine, which, for a number of pandemics that we've had recently, we've not had that solution. You have given us answers without realising that you actually had.

DF: Let me talk about that second month. Agility is very important in the government. To be able to respond quickly, to shut down or to tighten the screws is good. I don't believe that the second month would be exactly the same. They might tighten up or they might ease a few things off. In Singapore, they're really very tactical. And they might say, ‘You know what, we can open up those businesses again, but we got to keep those ones closed’. There will be tweaking along the way in that sort of agility. If things are going well in a month, I would be surprised if they say, ‘Okay, let's open up’.

ED: Thank you very much, professor. We hope that we can draw from you again, as we navigate our way through this crisis.

Featured Guest:
Professor Dale Fisher

Chair, Global Outbreak Alert and Response Network (GOARN) Steering Committee, World Health Organisation (WHO); Chair, Infection Control, National University Hospital, Singapore


Emmanuel Daniel

Chairman, The Asian Banker

About the series:

The COVID-19 Series is a collection of radio sessions that will be broadcast live on social media platforms to about 30,000 listeners in the financial services sector to survey the impact of the pandemic across the globe, potential aftershocks businesses may face and possible line of action in the days ahead.


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