Transcript: Liu Xin interviews Sten Vermund on virus origins tracing

The U.S. intelligence community has failed to shed any new light on the origins of SARS-CoV-2, and no evidence had been found to suggest that a lab in Wuhan was unsafe or tinkering with the virus. This did not come as a surprise for many given the deep scientific nature of thus task. 

But where should people look next? What is holding up the progress of the COVID-19 origins study? What are the ramifications of the anti-China rhetoric peddled by politicians in some countries on cross-border scientific cooperation? Earlier, Liu Xin spoke with Prof. Sten Vermund, Dean of the Yale School of Public Health. He is an infectious disease epidemiologist focusing on diseases in low and middle-income countries. Below is a transcript of the interview.


Liu Xin: Let's talk about the origins tracing study of COVID-19. Where most likely do you think COVID-19 originated? How do you regard the equivalence given by some in the scientific community to both the natural origins hypothesis and the lab leak hypothesis?

Dr. Sten Vermund: These are excellent questions. We believe that coronaviruses are largely in bat populations. There were four coronaviruses circulating in humans before SARS. Then we had SARS, then we had MERS. Now we have the novel coronavirus. So that makes seven in total.

The previous six seemed to be of natural origin. We have not had the good fortune in the case of novel coronavirus to identify a clear intermediate animal host. There's been an intensive search, but it's not obvious whether something similar to SARS occurred, such as a wet market exposure in sort of the exotic food industry, or whether there was some other exposure. The lab accidents hypothesis doesn't have any evidence to back it up, so it remains just that – just a hypothesis.

Liu Xin:  But by and large, you believe the novel coronavirus came from nature? 

Dr. Sten Vermund: It's far more likely that it came from nature than through some laboratory accident. The virology lab in Wuhan, as with modern virology labs around the world, take extraordinary precautions for the security of their products and the personal protective equipment for virologists working with potentially serious agents is very fastidious. And I think it would be very improbable that a lab accident were responsible for this release.

The Chinese Center for Disease Control and Prevention, Beijing, China, September 1, 2020./ CFP

The Chinese Center for Disease Control and Prevention, Beijing, China, September 1, 2020./ CFP

Liu Xin: There have been multiple studies about possible earlier emergence of SARS-CoV-2 in other parts of the world, prior to Wuhan. 

For instance, in Europe, in Italy, there has been this paper where researchers believe or assess that there is a high possibility that COVID-19 was already circulating in northern Italy in late June to late August of 2019.

And similar studies also emerged in the other parts of the world, for instance, in the United States. You must have also read where they analyzed blood samples from the American Red Cross, where they found that, you know, the actual emergence time of this disease is earlier than the believed January of 2020. Instead, it's believed to be somewhere in early December 2019, if not earlier. So, what do these findings tell you, reveal to you, about what may have happened before Wuhan?

Dr. Sten Vermund: These are intriguing and confusing reports. We had the same phenomenon with HIV. HIV was not recognized until about 1981. But there are a number of studies looking at blood samples from 1975, even 1965, there's one study from the 1950s, stating that there was HIV and humans at that time.

Unfortunately, it's hard to replicate these studies when they come from unique blood specimens. One can't be absolutely sure. We rely very heavily on replication in science.

The studies from Italy, the United States and elsewhere, suggesting that novel coronavirus, the SARS-CoV-2, actually was in humans well before the Wuhan outbreak, that falls in the same category. Very intriguing and very suggestive, but not very definitive, because we would like to see replication.

In these other reports, they were not associated with a clinical outbreak. So we didn't fill up the hospitals with patients. If this virus was circulating, perhaps it was a different strain, a different variant. Perhaps it was not as pathogenic to humans. These are the sorts of things people are trying to investigate right now.

Liu Xin: Where do you think people should look next for clues if finding the origins of SARS-CoV-2 is very important?

Dr. Sten Vermund: The tie between bats, intermediate hosts and humans is the most productive line of investigation, in my view.

Bat sampling in a laboratory in Ratchaburi Province, Thailand, September 12, 2020. /CFP

Bat sampling in a laboratory in Ratchaburi Province, Thailand, September 12, 2020. /CFP

Liu Xin: So, you must have been reading the press. And obviously, there has been, I don't know whether you notice, but there has been a large volume of reports, even editorials pointing to the Wuhan lab leak hypothesis and pressing China to open it up or to accept audits, even if scientists have already visited. What do you make of such a push for so-called greater transparency on China?

Dr. Sten Vermund: I don't think it should be unique to China. I think all of the world's virology labs and biology labs that handle potentially dangerous substances should cooperate with the World Health Organization, and they should cooperate with each other to try to maintain safety standards at the highest level.

This is why licensure of such labs is done in China, as well as it is also done in Europe and North America, why there are rigorous safety protocols in place where you can have spot audits, where visitors come in representing regulatory agencies to check that everything is being done properly.

We've had quite a number of laboratory errors around the world, including in the United States, so we must maintain a strong level of security and vigor.

In the United States, you may recall, in 2001, the month after 9/11, we had the anthrax outbreak, and this was a bioterrorism event that seems to have been promulgated by a former employee of a major bio-secure laboratory. And it looks like he stole the anthrax spores from the laboratory and used them for domestic bio terrorism.

So how can someone take a product and deliberately removed it from the lab, and nobody else knows? 

That's an example of where we have to be very vigilant in laboratories. And that goes for Fort Detrick, Maryland, and that goes for the CDC and that goes for the China CDC and that goes for the Wuhan virology labs.

All of them need to be guaranteed secure and safe. I have no evidence that the Wuhan lab was not doing a good job. In fact, the WHO investigation suggests that it was doing a good job. And now the Biden administration, those data are not available fully yet, but they seem to be, from the executive summary, there is no information to suggest the Wuhan lab was unsafe in any way.

The Wuhan Institute of Virology in Wuhan, central China's Hubei Province, January 14, 2021. /CFP

The Wuhan Institute of Virology in Wuhan, central China's Hubei Province, January 14, 2021. /CFP

Liu Xin: Yeah, exactly. As you mentioned, on August the 27th, the U.S. intelligence community after a 90-day investigation, failed to come to any kind of conclusive assessment as to the origins of COVID-19. Of course, we do not know the full content of that report. What is your comment on what we know from the report and its findings?

Dr. Sten Vermund: I only know what I've read, which is limited, similar to what you've read. It looks like it will be an inconclusive report. They will not be able to assess the Wuhan lab security, and they will not be able to make any kind of conclusion. It seems not to have been a fruitful investigation. 

My own view is that the intelligence agencies of the United States may do a fine job in assessing political or military vulnerability or risk, but I'm not sure they're the most qualified to evaluate a virology lab.

Liu Xin: What do you think has led to the current impasse or pause, let's say, in the progress toward understanding the origins of the virus? What do you think are the forces, if there are any, that have been behind such a stalemate?

Dr. Sten Vermund: That's an excellent question. Scientists like to collaborate with each other. And politics rarely interferes. We would like to get to the bottom of a mystery and find out where, for example, coronavirus came from.

I would love to have a bilateral arrangement, the Chinese government, U.S. government, both fund teams, that would actually work together. Study bat virus, coronaviruses, study potential intermediate hosts, try to get to the bottom of the origin of the virus. If they want to look at laboratory safety, they can do that too.

Right now, our collegial relations are not what they used to be. I can imagine a study like that being done 10 years ago, and both governments being very supportive. But today, we are paying the price of the anti-Sino rhetoric of our previous president. And I think our Congress has, unfortunately, taken a sort of negative view of China. 

But we scientists don't share this view. We think that Chinese science is powerful, and Chinese scientists are among the leading thinkers worldwide. We welcome the opportunity to collaborate with Chinese scientists to get to the bottom of important medical mysteries.

U.S. President Donald Trump holds a protective mask during the first presidential debate in Cleveland, Ohio, U.S., September 29, 2020. /Getty Images

U.S. President Donald Trump holds a protective mask during the first presidential debate in Cleveland, Ohio, U.S., September 29, 2020. /Getty Images

Liu Xin: Who should be leading this job? I mean, right now, there has been a mechanism under the mandate of the World Health Assembly resolution. A group of international scientists have been selected to come and collaborate with Chinese scientists, and they did some job, and they came up with a report. But so far, it has been stalled.

The report has come under a lot of criticism that these group of scientists have to come out and publish an explanatory opinion piece in a scientific magazine most recently. So, who should be assigned to do this very important job under the existing environment that we have?

Dr. Sten Vermund: First of all, I don't think you can get to the bottom of a major scientific question with a two-month review. Where do these viruses come from? Are they actually of bat origin, which is what we think? Which animals might they be infecting? Which animals might be most likely to result in human infection? These are the big questions, and these cannot be answered in 30, 60, 90 days. 

So we're going to need strong multidisciplinary teams of scientists, preferably an international team, which will increase the credibility of science, I think.

Liu Xin: Yeah, indeed, you're talking about a very ideal situation, but it seems to be very difficult at this moment, right? To have this kind of pure ideal scientific collaboration. But anyway, that's the kind of wish or idea that should be expressed to, you know...

Dr. Sten Vermund: I don't think we should give up. I don't think we should give up because top Chinese scientists are best friends of top American and European scientists. These people can work together like that. So, I think it may be time for some of our political leaders to let bygones be bygones. 

U.S. President Joe Biden speaks during a ceremony celebrating the 31st anniversary of the Americans with Disabilities Act at the White House in Washington, D.C., July 26, 2021. /Xinhua

U.S. President Joe Biden speaks during a ceremony celebrating the 31st anniversary of the Americans with Disabilities Act at the White House in Washington, D.C., July 26, 2021. /Xinhua

Liu Xin: I hope that is the case, too. Let's talk a bit about the new variant, the kind of threat that COVID-19 continues to pose to us. Now, at this moment, a new variant called Mu has just been added to the WHO's list of variants of interests.

And cases of this variant have been reported in the U.S., in Colombia, and the Republic of Korea and Europe. How serious a threat is this likely to pose based on what we saw about Delta already?

Dr. Sten Vermund: We don't know yet. We simply don't have enough information. The same is true for Lambda variant, which was also described not long ago. RNA viruses mutate at very high rates.

And that's true for HIV, that's true for influenza, and it's true for coronavirus. Because we have so many people around the world who are infected with coronavirus, the replication happening in humans is happening, multiplies by millions and millions of people. So there inevitably will be variants that emerge that are not self-destructing.

Most variants cause a defect in the virus that makes it less competitive and less able to replicate. But occasionally, a mutation, such as the one in the Delta variant, can actually give the virus a competitive advantage in survival. That's why in my state of Connecticut here in the United States, it's almost all Delta, because it's crowded out the other variants.

Liu Xin: Is there anything that people can do to try to tame or at least slow down the rate of mutation? Or it's really out of our control, and we can only try to catch up with the speed of vaccination and to add booster shots, to try to tame the new variants?

Dr. Sten Vermund: There are definitely two things that people can do to try to help tame variants.

Number one is to get vaccinated because if you stimulate your immune response to see the virus through the vaccine, and then if you do get infected later on, we would expect much milder disease. And that will likely reflect much less viral activity and viral replication. 

Second way is what China has done, which is a rigorous public health application of classic tools, such as masks, physical distancing, control of transportation, indoor air quality, outdoor activities, widespread testing, hand hygiene.

So, all of these traditional public health strategies also reduce replication of virus by limiting viral spread. 

A worker prepares to receive his COVID-19 vaccine in Antipolo City, Philippines, August 17, 2021. /Getty Images

A worker prepares to receive his COVID-19 vaccine in Antipolo City, Philippines, August 17, 2021. /Getty Images

Liu Xin: So, there are two different kinds of approach. One is what China does - try to get it down to zero. And the other is like, for instance, in the UK where they vaccinate as many people as possible, but then try to live with it. And then you have something, which is happening in the United States. You have a certain population, which refuses to be vaccinated.

So, in this kind of mixture of responses, is the virus always going to find some kind of free room to develop, to flourish, and to mutate and continue to exist? How long is it going to last?

Dr. Sten Vermund: If in places like the UK and the U.S. we can achieve herd immunity, such that enough people are vaccinated, that the rest of the transmission cycle sort of dies out. You end up with very few new infections. Because if you have an infectious person, but most of the people around this person are immune, then that's severely limits the spread of the virus. China can accomplish the same thing with widespread vaccination.

So at that point, perhaps society can more or less get back to normal. However, I think the donor nations, like China, the Europeans, North Americans, will be under a strong self-interested as well as humanitarian motive to help the low-income countries also vaccinate their populations. Because if we control viral spread in middle-income and high-income countries, then it will still be seen in low-income countries. So, it's in everyone's self-interest to enable them to also vaccinate.

I was in the country of Chad last week in central Africa, and less than one-tenth of one percent of the population has been vaccinated to date.

There are many countries that have received a small fraction of the vaccine that they need and have deployed even less. In so far as we're able to help those nations cover their population, then we can have a more definitive global solution.

A COVID-19 patient speaks to medical staff, at the Farcha provincial hospital in N'Djamena, Chad, April 30, 2021. /VCG

A COVID-19 patient speaks to medical staff, at the Farcha provincial hospital in N'Djamena, Chad, April 30, 2021. /VCG

Liu Xin: How about the situation in those countries that you just mentioned? For instance, of course they don't have the protection of the vaccine, but is the virus running rampant or with some traditional measures, they are able to more or less keep things under control?

Dr. Sten Vermund: It's a mixed setting. Some countries like South Africa, India, Brazil have struggled mightily and have had tremendous pandemic spread.

Other countries, like the one I was in, in Chad, have not seen much serious COVID today, partly because of relative isolation and strong border controls, particularly airport controls. The borders themselves are quite porous.

So, people for example in N'Djamena, the capital of Chad, is right across the river from Cameroon, and the bridges are full of people coming and going all hours of the day and night. So, the borders themselves are porous, but the airports are the most notorious for people bringing virus in from far away. There, they've had very rigorous control. Testing is required before they get on the airplane, testing is required as soon as they arrive.

In fact, most of the testing in Chad has been done on travelers. So, to date, they don't have a serious epidemic. And it gives us the opportunity, it's a limited window of time, to aggressively vaccinate before they have a huge surge of virus.

A doctor's office advertises the COVID-19 vaccine in a neighborhood near Brighton Beach in the Brooklyn borough of New York City, July 26, 2021. /CFP

A doctor's office advertises the COVID-19 vaccine in a neighborhood near Brighton Beach in the Brooklyn borough of New York City, July 26, 2021. /CFP

Liu Xin: Yeah, however, there's a great inequality, as you mentioned, in the distribution of vaccines. China realizes that China has been speeding up domestic vaccination, trying to provide and export vaccine and build joint ventures in other parts of the world. The United States, on the other hand, and I'm not trying, I'd hate to compare these two in one sentence, but it's a fact that the United States has been criticized for hoarding vaccines, even as many of these vaccines are about to expire. So, what options do you see the United States have in the speeding up provision of these global public goods?

Dr. Sten Vermund: It is unacceptable that we have such bad inventory management and logistics that we would have expiring vaccine. There is abundant opportunity to use that vaccine, even in nearby countries, helping Canada, helping Mexico, helping Caribbean countries. So we should not be seeing any vaccine expire.

I was pleased that the Biden administration announced a couple of weeks ago, a half-billion-dose donation to the global vaccine effort. And I think they'll be working with COVAX, the partnership of Gavi, with WHO and a number of other partners.

So, that's good, and I hope that is the first installment of another half billion and another half billion. There are 5 billion doses of coronavirus vaccines that have been given to humans on earth.

If I'm not mistaken, at least two-fifths of that comes from China alone, maybe more than a half. So, I'd very much would like to see the Europeans and the North Americans be as aggressive in provision of vaccines as the Chinese have been, because I've been seeing the Chinese vaccine as the very first one coming into a number of countries. 

I was in Dominican Republic about a month ago. And all of their early vaccine was from China. In Chad, all of their early vaccine was from China.

So, I do see substantial efforts being made by the Chinese to get vaccines out to countries that need it. And I'm hoping that the European, North American and other donor nations will follow suit.

Liu Xin: We are running out of time, but it's been a great conversation and so informative. Thank you so much Professor Sten Vermund, Dean of the Yale School of Public Health, joining us from New Haven, Connecticut. Thank you so much.

Dr. Sten Vermund: Thank you. 

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