The countries getting it right.

The world can learn lessons from how China, South Korea and Singapore have handled covid-19, the WHO's Bruce Aylward tells Jessica Hamzelou.

LAST month, the World Health Organization's assistant director general Bruce Aylward set out to learn more about China's response to the covid-19 outbreak and generate recommendations for China and other countries. He told Jessica Hamzelou what we have learned so far.

Jessica Hamzelou: Cases in China are declining – we are now only seeing a handful of new reported cases every day. Does China have the virus under control?

Bruce Aylward: It has absolutely turned it around. [But] governors, mayors and others that I talked to in China would never say things were “under control”. When I asked them if they felt good about falling cases, they said no. They said they were building more beds and buying more ventilators because they were worried that they might never get something like this – a new virus that we don't understand – under control.

Now they are planning to open up all the travel restrictions, get people back to work and get students back to school. But their feeling was that this is going to remain in the population and raise its ugly head, and they have to be able to respond rapidly.

How did China get to this point?

China did something that most other countries would not even have tried, and many people thought would have been impossible. It used fundamental public health approaches – such as case finding and contact tracing – to stop a respiratory virus.

That seemed almost impossible as a premise because respiratory viruses transmit so effectively and efficiently – typically the only way you can stop them is with a vaccine or pharmaceutical treatment. What China did provides a lesson for infectious disease epidemiologists.

Does that mean China's extreme lockdowns were the right way to go?

Everyone always starts at the wrong end of the China response. The first thing it did was try to prevent the spread as much as it could, and make sure people knew about the disease and how to get tested.

To actually stop the virus, it had to do rapid testing of any suspect case, immediate isolation of anyone who was a confirmed or suspected case, and then quarantine the close contacts for 14 days so that they could figure out if any were infected. Those were the measures that stopped transmission in China, not the big travel restrictions and lockdowns.

14% Roughly how many people in South Korea are 65 or older

Stopping the movement of people doesn't stop the virus jumping from person to person, it just prevents those people from moving to other places. The travel restrictions and lockdowns were to give them time to get the other things in place and actually stop transmission.

When I spoke to Italy the other day, they said: “We've got these lockdowns in place.” I said: “Great, you've done the hard part, now you have to do the really hard part, and that is making sure the cases are effectively isolated.”

Italy is the most affected country in Europe. What's happening there?

What's happening in Italy, and in many other countries in Europe, is that they are treating the mild cases at home. In some countries they are not even testing them. They are saying if you have a cough and high fever, stay at home.

But the problem then is that [people] don't know that they have the disease, they haven't had it confirmed. After a couple of days people get bored, go out for a walk and go shopping and get other people infected. If you know you are infected you are more likely to isolate yourself.

Generally in a population, around 60 to 80 per cent of those affected are going to have mild or moderate disease. If those people are all out of hospital, most of your cases are at home, but not isolated. In China, they found that didn't work. They had to get them isolated in hospitals or dormitories or stadiums. The main goal was to keep them from getting bored.

Which countries have responded well to the outbreak?

There are lots. Look at South Korea – it has been pretty rigorous about testing all the suspect cases and finding all the contacts. In the past couple of days, we have seen that, instead of that relentless upward creep in cases, it seems to have turned a corner, which is positive.

Singapore is another country that has been hit with importations again and again, and they are jumping on them, tracing all the cases, tracing all the contacts, professionally isolating them all. It seems to be doing pretty well, even though it has got relatively big numbers.

Canada had importations into four or five different provinces. And in almost all of those it has been able to keep the numbers fairly low, following a very similar rapid test approach. And in all those places, it's very easy to get tested as well.

Do you think these countries have learned lessons from other, past outbreaks?

Oh absolutely. When you look at Singapore, South Korea, China – why are they so aggressive in terms of case finding and contact tracing for coronavirus? Well they were all hit by SARS. Similarly, if you look at Canada, it had a big SARS outbreak back in 2003, with hundreds of cases.

[These countries] saw the devastation a coronavirus can cause – they jumped right on it.

Why has the case fatality rate been lower in South Korea than in other countries?

It has a relatively young population. The population aged over 65 in South Korea is something like 14 per cent – half that of Japan and much lower than Italy. A case fatality rate of around 1 per cent – close to what we are seeing in South Korea now – is what we see in a young population. But the case fatality rate has been creeping up over time. The thing that I would remember, even right now in South Korea, is that [the fatality rate] is still tenfold higher than seasonal flu.

Is that why it has been so bad in Italy, because the population is older?

We are not sure. I saw some data from the north [of Italy] that suggests around one-third of cases are being managed at home. Some of the milder cases just aren't being tested and officially diagnosed. That's part of the problem.

The second is the older population. The third is it is also very early in their outbreak, and that can sometimes be where you see higher mortality among older people, and it distorts the picture.

What do you think of the UK, which hasn't been taking as strong measures as some countries?

People have different reasons for taking different measures at different times in an outbreak. Chris [Whitty, chief medical adviser to the UK] is one of the brightest, most sensible and careful people I know. I'm not going to second-guess anybody at this time.

How effective is closing schools?

That's a tough one. The data [on this is] for a different disease – it's for flu. Kids get these rip-roaring flus, and the whole classroom gets sick. The kids get their families infected. Parents have to stay at home with the kids, and then they get sick, go to work and infect others.

But one of the curious things with [covid-19] is that we have not seen school outbreaks. I talked to my colleagues in South Korea, in China, in Italy, everywhere – no one has seen school outbreaks. They have seen situations where a teacher is infected and they have infected kids, but that is different to the kids all getting each other infected.

When you talk about school closures, you want to know, is it going to reduce the intensity of transmission? We know that it probably won't reduce the number of sick people very much, because not many kids get sick. But what we don't know is, are kids getting infected and we just can't see it? And if they are, are they carrying it back to their families? Even there we don't have a lot of data to suggest that kids are infecting their families. So as a result, countries have done things differently.

Lockdown is the hard part. Making sure cases are effectively isolated is the really hard part

There is a chance that when cases decline in countries and restrictions loosen, we will see more infections. What happens then?

China decided that it cannot afford to wait for cases to go to absolute zero – not knowing if they ever will – so it decided to strengthen its whole system so that it could live with the disease if it had to. It is building additional capacity to isolate people, and it is building additional ventilators. It is planning to be able to manage low-level disease and prevent large outbreaks. It's a very sensible way to plan.

It's wishful thinking to think that the virus is going to disappear altogether. People keep saying that maybe in the warm season it will. Last time I checked, Singapore was very warm, and it's roaring away there.

Have you seen anything like this outbreak before?

As soon as you [compare the disease to others], you are dead. This is a new disease. Respect it and learn as it evolves. The more you lean on your old [experiences], the more mistakes you are going to make.

Aylward spoke to New Scientist on 13 March. The interview has been edited for length and clarity.

Listen to the latest on covid-19 Download the New Scientist Weekly podcast newscientist.com/podcasts