Disruptive Technologies

WHO: COVID-19 didn’t leak from a lab. Also WHO: Maybe it did

By Filippa Lentzos, February 11, 2021

The joint World Health Organization-China mission to investigate the origins of COVID-19 reported its highly-anticipated findings at a press conference in Wuhan, China, earlier this week. Far from clarifying where the deadly coronavirus could have sprung from, members of the mission echoed Beijing’s narrative and left more questions than answers. Perhaps most troubling, they outlined a precedent for outbreak investigations that could stifle societal debates about the risks we’re willing to take for high-risk lab research on pathogens.

At the Feb. 9 briefing, the co-heads of the mission, Peter Ben Embarek and Liang Wannian, laid out the four origin hypotheses that formed the basis of the mission’s investigation:

    • The novel coronavirus, SARS-CoV-2, jumped directly from an animal species to humans.
    • The virus leapt from one animal species to an intermediary animal host in which the virus adapted more before jumping to people.
    • The virus was introduced to Wuhan via the food chain, for example from frozen products.
    • The virus was accidentally released through a lab-related incident.

The mission concluded that the second hypothesis, that the virus jumped from one species to another before infecting people, is “the most likely pathway.” While the mission reported that the direct spillover and food-chain ideas needed more investigation, Ben Embarek said the team had dismissed the idea that a lab-leak hypothesis as “extremely unlikely” and said it wouldn’t be pursued any further.

But days after the presser, the remarks by Ben Embarek and the team were undercut when World Health Organization Director-General Tedros Adhanom Ghebreyesus said no hypotheses had been ruled out: “I want to clarify that all hypotheses remain open and require further study.” Where the WHO investigators go from here remains to be seen.

In Wuhan, Ben Embarek laid out several reasons why the team was ruling out the lab leak hypothesis. “Nowhere previously was this particular virus researched or identified or known,” he said. “There had been no publications and no reports of this virus, or another virus extremely closely linked to this, being worked with in any laboratory in the world.”

Yet, what makes the investigative team so certain of this? Not everything that is researched in labs is published. And from the published record, we know that scientists at the Wuhan Institute of Virology, one of the labs in Wuhan that researched bat coronaviruses, had renamed viruses with sequences closely resembling SARS-CoV-2 in an apparent attempt to obfuscate their previous work with these viruses before the pandemic. Then there’s the fact that the Wuhan Institute of Virology’s virus database was taken offline at the beginning of 2020 for “security reasons.” Did the investigative team have access to the database? Did they scrutinize other lab records?

Lab accidents happen, Ben Embarek acknowledged. But he said they are “extremely rare events” and that “it was very unlikely that anything could escape from” the Wuhan Institute of Virology’s secure (biosafety level-4) high-containment lab. Yet, as Alison Young, an investigative journalist with years of experience researching lab biosafety breaches for publications like USA Today, tweeted, “accidents aren’t rare. What’s rare are accidents causing documented outbreaks. But those have happened, including with the first SARS virus.”

While the Wuhan Institute of Virology’s biosafety level-4 lab has gotten the most media attention, coronavirus research was also undertaken at the institute’s lower containment (biosafety level-2 and -3) labs, as well as at other institutes in the area like the Wuhan Center for Disease Control and Prevention. What evidence does the World Health Organization team have that no safety lapses could have occurred in these other labs? Or during the high-risk fieldwork Wuhan-based researchers undertook to collect coronaviruses from live bats?

Ben Embarek also said the team’s judgement was based on “long, frank, open discussions” with management and staff at the Wuhan Institute of Virology, in which they provided “detailed descriptions of their research both present and past on all projects involving bats and coronaviruses and more advanced projects.” The institute staff, he said, “are the best ones to dismiss the [lab-leak] claims and provide answers to all the questions.”

Yet, how does the investigative team know protocols were followed? How do they know a researcher did not become accidentally infected without showing symptoms? As Stanford University microbiologist David Relman told The Washington Post: “If the only information you’re allowing to be weighed is provided by the very people who have everything to lose by revealing such evidence, that just doesn’t come close to passing the sniff test.” He suggested the team should have sought complete, detailed records from the laboratories about their experiments and the raw genomic sequence data of their research going back a decade.

The publicly-available genetic and epidemiological evidence collected so far about SARS-CoV-2 and the outbreak does not exclude the possibility of a lab leak.

Taken as a whole, the lab-leak theory remains a serious possibility; the World Health Organization’s investigative team will need to present any new evidence it used to rule out the theory when it releases its mission report. Additionally, the mission’s own terms of reference notes that there is currently no evidence of SARS-CoV-2 transmission on food products. At the press conference Ben Embarek said, “we don’t really understand if the virus can transmit to humans and under which conditions this could happen.” On what basis, then, is the team assessing the likelihood of a food-chain origin for COVID-19 as being higher than a lab-leak origin?

But it is not just the marginal theories that the World Health Organization needs to weigh in on with evidence. The investigative team’s principle theory—and that of much of the scientific community at large—is that the virus originated from bat populations. This is supported by genetic studies of SARS-CoV-2 isolated from humans. However, because there is usually very limited close contact between humans and bats, the team’s theory is that rather than bats infecting humans directly, they first transmitted the coronavirus to some intermediary species, an animal that people handle more frequently.

The intermediate animal host could be a domestic animal, a wild animal, or a domesticated wild animal. As of yet, the creature has not been identified. There is precedent for spillover through intermediate hosts. The first known coronavirus to have caused serious illness in humans, SARS-CoV, also likely originated in bats, which then infected civet cats (a farmed wild animal), which then infected humans. Once the virus made the leap to humans, it spread throughout the world, causing the severe acute respiratory syndrome (SARS) outbreak of 2003. In 2012, another coronavirus, MERS-CoV, spread from bats into camels and caused cases of Middle Eastern respiratory syndrome (MERS). Yet, in the case of COVID-19, after more than a year of searching, no intermediate host has been found. While clearly still a possibility, what supporting evidence is there suggesting the intermediate host theory should be ranked so much higher than other possibilities? Just because there is precedent for spillover through intermediate hosts is not a good enough argument—biosafety lapses have happened before, too.

The team’s messaging in Wuhan aligned closely with Beijing’s narrative of a possible origin source of COVID-19 outside China’s borders. Throughout the briefing, speakers repeatedly stressed that the 12-day Wuhan investigation was only “the first part” or the “China part” of a larger investigation not limited by geographical location. That the World Health Organization and China had reached a political settlement was also clear in the mission team’s terms of reference—which had to be agreed on by both the organization and the Chinese government. The terms of reference document emphasizes that “the virus may have circulated elsewhere” before it was “identified through surveillance in Wuhan” and that “the global origin tracing work is therefore not bound to any location and may evolve geographically as evidence is being generated, and hypotheses evolve.”

The document is firmly in line with Beijing’s preferred COVID-19 origins story, the idea that SARS-CoV-2 may have initially spilled over in Italy, France, the United States, or elsewhere and circulated undetected before it was first identified in Wuhan. As journalist John Sudworth, reporting from the Wuhan press conference for the BBC, said, “the WHO arrived here, insisting this was going to be all about the science, and yet signs of the politics have been there every step of the way, from the wrangling about access and timing, from the team’s reliance not on its own investigation but on data provided by China. Questions about how independent these findings are from China’s own narrative are unlikely to go away.”

Alina Chan, a researcher at the Broad Institute of MIT and Harvard, commented on Twitter that the investigative team’s findings have now set such a high bar for launching an investigation into potential lab origins that in future, one couldn’t be launched unless there was already incontrovertible proof for it. “Problematically, the countries that have the most leverage over international organizations also tend to be the countries investing the most in these types of high risk pathogens research,” she wrote.

Indeed, scientists, funders, and publishers with heavily vested interests in potentially pandemic virus research—like work on coronaviruses—could well use the World Health Organization’s investigation to stifle any further discussion of risky virus studies. That would be a real lost opportunity, because beyond whether the pandemic resulted from natural spillover or laboratory research, the origins question feeds into bigger societal debates that we still need to have about the sorts of risks we’re willing to take in the name of research.

As the coronavirus crisis shows, we need science now more than ever.

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  • Is it a cliche to note that this reminds me of The Stand, which begins with a virus escaping a laboratory and proceeding to infect the world population?

    (Full disclosure: I've never read the book, only seen the 1994 miniseries)

  • The WHO’s Ben Embarek says a lab-leak is “extremely unlikely”. Agreed. But it’s also incredibly unlikely for a coronavirus pandemic to emerge out of Wuhan through natural zoonosis. Just 18 months ago, both scenarios would have been described as extremely unlikely. They are both very low probability events. But one of them happened. With little explanation, Ben Embarek dismisses one scenario but not the other.

    The current coronavirus pandemic started in a city where there are labs conducting research into coronaviruses. For years – long before this pandemic – biosafety experts and concerned scientists highlighted the risks posed by certain types of virus research. The Bulletin website has repeatedly highlighted concerns. Just a few months before the pandemic, Lynn Klotz authored an article on this website with a title that speaks for itself: “Human error in high-biocontainment labs: a likely pandemic threat.” The mainstream media highlighted concerns, too -- repeatedly (even if some of those same media outlets won’t now touch the lab-leak hypothesis with a bargepole).

    The WHO’s Ben Embarek says “nowhere previously was this particular virus researched or identified or known”. This is an odd thing to say by someone with a rational scientific mind. No one can definitively say whether the virus was being researched or identified or known anywhere. It is naive to believe that the Chinese state would have admitted it if the virus was being researched in one of its labs. They would not have admitted it. They won’t ever admit it.

    Regarding the deleted WIV databases, I’d speculate that the data in those databases is incriminating – but that it is not conclusive. I expect some western scientists know full well what’s in those databases. If the data fully exonerates the WIV, you can bet it would have been shared already. But if the data conclusively proves the WIV’s responsibility for the pandemic, those western scientists wouldn’t risk their reputation by staying quiet. In my view, it’s most likely that the data further incriminates the WIV without being a smoking gun.

    I expect this isn’t going to be solved any time soon – unless an animal source for the virus is found (proving natural zoonosis), or a whistleblower inside China steps forward (proving lab leak).

    • There's a lot of focus upon Wuhan and its lab. However, I'd like to see the evidence that pinpoints Wuhan as the origin of the zoonotic transfer. It's true it may have hopped outside of China and was brought to Wuhan. It's also true it could have hopped between (say) bat reservoirs and people in a couple of places.

      The failure is that we collectively lacked the cooperative international system of public health and zoonotic monitoring we should have had. And, judging by how things are going, as soon as this is swept into some poor corner of the world and most can get on with their lives, the public will to spend billions to set up such a system is going to evaporate. And, then, when the next one comes, the public will grumble one more time.

  • What is undebatable is that if an air-borne virus such as Covid-19 gets out in a large urban city, it will spread rapidly thanks to mass transit and go global thanks to air travel long before local officials know they have a problem. In the U.S., Washington State and Seattle stopped the virus but New York City failed. That difference is because Seattle has little mass transit and lower density housing with exterior doors while NYC has mass transit and building ventilation that spreads the virus indoors. That is why NYC has a death rate 50% higher than any state and why the pandemic exploded from NYC outward in the U.S.--not Seattle. Wuhan is a very large city like NYC. Lost the game because the outbreak was in Wuhan.

    The conclusions are simple. First, must reduce rick of such an outbreak starting in a large city.. Level 4 and maybe level 3 bio-facilities should be limited to locations outside smaller cities--certainly under a million in population. Accidents do happen and the owners of such facilities may or may not know if they had a release. Second, filtered air to limit airborne virus spread is a requirement for mass transit--not an option. The much lower rate of transmission in commercial aircraft relative city mass transit is because commercial aircraft use HEPA filters that filter out viruses. The virus went global because there were no barriers to slow spread,

  • This ignores the screaming obvious fact that viral pandemics around the world have been caused by the "bush meat trade", including HIV and Ebola. In China the leading candidate is the poor beleaguered Pangolin. They are harvested in large numbers for meat, and for their scales, used in the "alternative medicine" trade. The obvious first step in China is to stop harvesting Pangolins, and the US should stop the import of their scales. Fanning the flames of conspiracy theories is nonsense, when the obvious likely cause is clear, and simple steps can be taken to reduce the risk. Not only is almost all alternative medicine a hoax, but the risk associated with Pangolin harvesting vastly outweighs the marginal benefit it might provide.

  • Far as I'm concerned, by far the most probable place for a lab leak is the Wuhan Chinese CDC lab - for two teasons: 1) that lab is only Biosafety 2, but it was known to handle live bats, and 2) unlike the WUV, the CDC lab just so happens to be located...right across the street from the infamous Huanan Seafood Market (!!!)
    If you add in that of the first two officially admitted Wuhan Covid cases, one person worked at the market, but the other person only lived in the neighborhood and never visited the market - the CDC lab is definitely the place I'd focus on.

  • There might be one additional possibility for how this pandemic got started : the virus was present in the human population for a significant period of time, circulating at a low level. It might have gone undetected as a typical viral pneumonia. It was not transmissible enough to create case clusters for an extended period. Then, something happened. Maybe multiple mutations involving the spike protein function accumulated. Suddenly, the virus became not only deadlier, but much more transmissible..
    If this was the case, going back through patient samples should turn up some evidence. I have heard of some alleged patient and wastewater material from Italy and Spain that predate the pandemic that may point to this, but the credibility seems lacking.
    The lab leak appears to be one of the most probable explanations at this point, given how this virus was so highly adapted to human transmission as soon as it was identified.

    • If I understand correctly, the assays used to find those results from Italy and Spain were questionable.

      A more obvious place to look for evidence of earlier spread would be Wuhan, but unfortunately the Chinese government has been reluctant to provide full access to this data… as the WHO team discovered.

      I'm trying to be neutral, here, but it's difficult to understand what the Chinese motivation is, if not to hide something embarrassing. You'd expect them to want to find the intermediate host, and so prevent another disastrous spillover event from happening. Instead they seem almost disinterested.

      • Yeah, while China is in a state of flux both trying to communicate all around the world waving their flag of cooperation and also muting the not so flattering sides, it's hard to be conclusive whether this behavior regarding Covid points to one side or another. But it's definitely easier to think that we would have seen the open and cooperative China if this was just "it happened on our soil but it could have happened or originally come from anywhere". Though maybe their culture just sees this as a failure anyway and they're ashamed of even being connected to all this whether it's some stray bats.

        Also we can't fully trust Chinese numbers or intel, or estimate how their totalitaristic management methods helped in controlling the outbreak, but considering that at this point China's numbers are about <5% of the global total while US, Canada, South America, Europe and Russia in particular are still in major situation it's easy to think this disease is somehow more efficient on foreign people. Maybe a coincidence but still.

  • There is some sequence evidence suggestive of a lab leak if you dig deep enough (one good example is work by the very brave Alina Chan at the Broad Institute). The sequence is the same as a 2013 coronavirus isolated from miners in China, except for a EcoRI restriction enzyme site at the region that encodes the spike protein, followed by swapping in pangolin sequence that will enable the virus to bind to human ACE2 receptor, and by the addition of the furin cleavage site that is critical for the pathogenesis but not found in any other coronavirus (only in other lethal types of viruses). Seems engineered to me. Also would not be hard for an accidental lab leak to happen - it is not too uncommon. Finally, the bats in the wild are 100s of miles away from the institue, but WIV was doing this type of research and is at ground zero. You can see by checking on pubmed for WIV papers.

  • The WHO investigation is, I feel, very informative precisely because of what they have failed to uncover. Specifically, they asked for interview records setting out the questions asked of the early cases - who they were, what they were doing, where they had been - which would surely have been the foundation of any epidemiological investigation. The WHO team were denied these records. Why?

    Two choices spring to mind.

    Firstly, that the Chinese researchers never even considered the possibility of an accidental release of the virus from one of their labs. Seems unlikely, since one of the professionals working there said it was the first thought that crossed her mind, in one of the reports I've seen. We're told that staff gave regular blood samples which were stored on a precautionary basis and have subsequently been tested, which suggests this was always a concern. But if the early cases were never asked questions along these lines, that would point to incompetence or evasion of obvious responsibilities. It would also mean that those records could not be cited one way or the other as evidence on the point.

    Secondly, that they in fact asked a great many questions about possible links to the laboratories, and places where people might have encountered staff working there, but had no conclusive answers. This would have undermined the idea that this hypothesis is 'extremely unlikely' and not worthy of serious consideration and might therefore politically inconvenient to reveal now.

    Or am I missing a third possibility?

    In the absence of a compelling non-lab-based explanation of how and why a zoonotic transfer would have emerged in Wuhan, the lab-based explanations logically need to be ranked first on the list and international discussions of how and where research into potentially devastating pathogens should be conducted need to follow.

    After the final tragic deaths in Birmingham, England, from the accidental release of smallpox in 1976, live smallpox samples were destroyed in most laboratories worldwide, including all in the UK. I agree with other comments that the location of high security labs must be reviewed.

  • Not a fan of conspiracy theories but the WHO has got be less servile to the Chinese and the Chinese Govt has to be more forthright. Just from this reporting, there are multiple Bat Coronavirus labs in Wuhan with varying levels of safety, and the city was the center of where this virus exploded but the Chinese say it came from "elsewhere?" Really? this is why I have wild theories. People need to fess up. The truth will out someday and maybe the WHO needs to be reformed to be less political and more scientific.

  • It seems like the author is pressing for the scenario of the virus breaking out of the lab. Why the press for this possibility being prominent? Is the likelihood that it could have been transmitted through those means that great to encourage the focus? I agree that you have to consider all options but the emphasis on dissembling seems overt and biased. Maybe I've been reading too many opinion pieces...