Michael Levitt is Professor of computer science and structural biology at Stanford Medical School and winner of the 2013 Nobel Prize in chemistry. He has been a close observer of the pandemic and the response from the outset through its movement to Europe, the U.K., and the U.S.. On May 2, 2020, speaking to the Unherd podcast and YouTube channel, he offered some compelling thoughts and observations, and a striking conclusion.
Below is a transcript of the parts I found most relevant.
Q: So you noticed that the curve was less of an exponential curve than we might have feared, in those early days?
A: In some ways there was never any exponential growth from the minute I looked at it, there were never any two days that had exactly the same growth rate — and they were getting slow…of course you could have non exponential growth where every single day they’re getting more than exponential — but the growth was always sub-exponential. So that’s the first step.
Q: [In the UK] we talk endlessly about the R-rate — the reproduction rate — and apparently that began very high, maybe as high as 3, and … [we’ve now] got it down below 1 in the UK. Intuitively, if there’s a high reproduction rate, you should see that exponential curve just going up and up.
A: Well no, wait, okay. The R-0, which is very popular, is in some ways a faulty number. Let me explain why. The rate of growth doesn’t depend on R-0. It depends on R-0 and the time you are infectious. So if you are twice as long infectious and have half the R-0 you’ll get exactly the same growth rate. This is sort of intuitive, but it’s not explained, and therefore it seems to me that I would say at the present time R-0 became important because of a lot of movies — it was very popular — talked about R-0.
Epidemiologists talk about R-0 but, looking at all the mathematics, you have to specify the time infectious at the same time to have any meaning. The other problem is that R-0 decreases — we don’t know why R-0 decreases. It could be social distancing, it could be prior immunity, it could be hidden cases.
Q: You’ve been observing the shapes of these curves and how the R-0 number tends to come down and the curve tends to flatten in some kind of natural way regardless of intervention. Is that what you are observing?
A: We don’t know. I think the big test is going to be Sweden. Sweden is practicing a level of social distancing that is keeping children in schools, keeping people at work. They are obviously having more deaths in countries like Israel or Austria that are practicing very very strict social distancing but I think it is not a crazy policy. The reason I felt that social distancing was unimportant is practicing very very strict social distancing, but I think it is not a crazy policy.
The reason I felt that social distancing was unimportant is that I had two examples in China to start with and then we had the additional examples. The first one was South Korea (yeah), and Iran, and Italy. The beginning of all the epidemics showing a slowing down, and it was very hard for me to believe that those three countries could practice social-distancing as well as China. China was amazing, especially outside Hubei, in that they had no additional outbreaks. People left Hubei, they were very carefully tracked, had to wear face masks all the time, had to take their temperatures all the time, and there were no further outbreaks.
So this did not happen in either in South Korea or in Italy or in Iran. Now, two months later something else suggests that social distancing might not be important, and that is that the total number of deaths we’re seeing in New York City, in parts of England, in parts of France, in northern Italy — all seem to stop at about the same direction of the population so are they all practicing equally good social distancing? I don’t think so.
The problem I think is outbreaks occurring in different regions. I think social distancing that stops people moving from London to Manchester is probably a really good idea. My feeling is that in London, and in New York City, all the people who got infected, all got infected before anybody noticed. There’s no way that the infection grew so quickly in New York City without the infection spreading very quickly. So one of the key things is to stop people, who know that they’re sick, from infecting the others. Here again, China has three very, very important advantages that are not high-tech that don’t involve security tracking of telephones.
What they involve is, number one, the tradition in China for years, of wearing a face mask when you’re sick. As soon as the coronavirus started everybody wore a face mask. It doesn’t have to be a hygienic face mask it just has to be a face covering to stop you spraying saliva, micro droplets of saliva on somebody you talk to. The second thing in China is that because they were so scared of the SARS epidemic in most airports, stations where you pay tolls et cetera, there are thermometers. Infrared thermometers that that measure your temperature. So having your temperature measured at every single store entrance — either with a handheld thermometer or with something mounted on the wall — is something completely standard in China. And the third thing is that almost all payments in China are made not using a credit card, so in some senses it is very much easier there to practice social distancing. Of course, in addition they know where people are.
Q: What’s your view of the lockdown policy that so many European countries and states in America have introduced?
A: I think it is a huge mistake. I think we need smart lockdowns. If we were to do this again, we would probably insist on face masks, hand sanitizers, and some kind of payment that did not involve touching right from the very beginning. This would slow down new outbreaks and I think that for example they found as I understand, that children, even if they’re infected, never infect adults, so why do we not have children at school? Why do we not have people working? England, France, Italy, Sweden, Belgium, Holland, are all reaching levels of saturation that are going to be very, very close to herd immunity — So that’s a good thing. I think the policy of herd immunity is the right policy. I think Britain was on exactly the right track — before they were fed wrong numbers and they made a huge mistake.