RACHEL MARTIN, HOST:

The World Health Organization, or the WHO, has been tracking the coronavirus and leading the global response to the pandemic from the beginning. At this point, nearly 240,000 people have been infected, and the death toll globally has now reached more than 10,000. So what has the WHO learned since the outbreak began? Let's put that question to Dr. Maria Van Kerkhove. She's the COVID-19 technical lead at the World Health Organization, and she also heads up its emerging disease and zoonosis unit.

Thanks so much for being with us this morning.

MARIA VAN KERKHOVE: Thank you, Rachel.

MARTIN: Is there something you didn't know last week that you know now?

VAN KERKHOVE: Yes. The answer to that is yes. It is happening so quickly. For example, some of the things that we're learning are about disease progression. You know, what do people start with? So what is the differences between COVID-19 and flu so that we could better inform people around that? We are constantly learning about, what are the interventions that countries are doing to bring this outbreak under control, to slow this outbreak?

MARTIN: So what does that mean in terms of testing? I mean, should countries be testing only people who are symptomatic? Or should there be an aggressive effort to test every single citizen?

VAN KERKHOVE: So we certainly do not have enough tests globally to test every single citizen, and we don't need to be doing that. What WHO recommends is testing all suspected cases. And we have definitions for what that means. And it's a combination of some kind of disease as well as an exposure to the virus itself.

We know that if - that there is a very strong approach to finding all the cases, isolating them and caring for them - finding all the contacts, quarantining the contacts and testing the contacts who develop symptoms. Those are the fundamentals to drive transmission down.

MARTIN: Based on the modelling that you no doubt do and all the information that you have gleaned about this disease over the past 12 weeks, what is your estimate for how long the pandemic lasts?

VAN KERKHOVE: What we know from multiple countries across Asia is that the interventions can slow this down - can essentially stop transmission. In China, there are zero cases over the last few days that have been locally acquired. The cases that we're now seeing in China are actually importation from other countries. This is unique. This is the first pandemic in history that we will be able - we have the power to slow down and to stop.

MARTIN: I have to ask, though - Italy has passed widespread restrictive social distancing measures. And in the north, those hospitals are completely, completely overwhelmed. It doesn't seem...

VAN KERKHOVE: Yes.

MARTIN: ...To be abating the crisis.

VAN KERKHOVE: Yes. So unfortunately, in several countries - we saw this in Korea as well - the situation will get worse before it gets better. Certainly, in Italy, they are seeing things in terms of their capacities in hospitals. They have a large number of people in ICU. They also have an older population demographic, and we do know that older people can have severe disease.

It comes down to, you know, how much they can do in terms of reducing that transmission. These interventions, social measures that they've put in place will help. It will take some time. There is hope. And I want the listeners to know that there is hope that we can turn this around.

MARTIN: Thank you for that. Dr. Maria Van Kerkhove with the World Health Organization.

Thank you again. We appreciate it.

VAN KERKHOVE: Thank you very much. Transcript provided by NPR, Copyright NPR.