On Jan. 30, 2020, Republican Sen. Tom Cotton addressed military leaders at a Senate Armed Services Committee hearing and presented a startling idea. At that time, the novel coronavirus was spreading around China and had killed hundreds of people, though it had not yet been identified in the U.S. Chinese officials said the virus had originated at a seafood market in Wuhan.
Cotton charged that China was “lying” about the origins of COVID-19. He raised another possibility: “I would note that Wuhan also has China’s only biosafety level-four ‘super laboratory’ that works with the world’s most deadly pathogens to include, yes, coronavirus.” What if the virus had instead originated there?
With that, the “lab-leak” debate came crashing into the public discourse. Cotton wasn’t the only one to ask about the virus’ origins; days before his remarks, a Daily Mail article raised the possibility of a lab leak too, and a scientific study in the Lancet noted that many of the earliest cases of COVID had no connection to the wet market. The debate gained substantial traction in 2021, when a group of researchers published a commentary in Science calling for further investigation into the origins of SARS-CoV-2.
The lab-leak debate has raged for three years now, without reaching a universally accepted resolution. There may not be a conclusive answer for a while: It took 29 years to definitively identify the source of Ebola, 26 years for HIV/AIDS, and 15 years for SARS.
I am not expert enough to fully evaluate each piece of evidence presented by the two sides. But right from the start, the “debate” itself was peculiar: It was justified by the hope that identifying the origins of COVID-19 would help us better prepare for future public health threats. As recently as November 2022, both the editorial board of the Washington Post and the editor in chief of ProPublica insisted that resolving the debate remains essential “to prevent future pandemics.” But in fact we already knew where the threat of future pandemics lies and how to fight them.
Over the past 50 years, the rate of outbreaks of infectious disease has more than quadrupled. At least 55 of those outbreaks have killed hundreds or thousands of people and have had the potential to become pandemic. But with only one possible exception—the “Russian flu” pandemic of 1977–78—every single one of these was either a previously unknown disease originating in animals (e.g., HIV/AIDS, Ebola, SARS, MERS, novel strains of flu) or an exacerbation of a previously endemic disease (e.g., dengue, malaria, cholera). Regardless of where the COVID-19 pandemic came from, it’s clear that the threat of pandemics in general comes from spillover of novel viruses from wild animals or factory-farmed animals to humans.
A pandemic could come from an accidental or malicious lab leak, of course. But researchers have reported that most infections resulting from lab research accidents are relatively mild. And a 2016 survey of biosafety level-three and level-four laboratories (the labs working with the most dangerous pathogens), carried out by a large, international team of scientists, concluded that “laboratory-acquired infections have been infrequent and even rare in recent years.”
The lab-leak debate, regardless of which side is right, has little to contribute to the question of where the threat of future pandemics lies or how to respond to that threat. The public health implications of the debate are already settled: Few scientists on either side would argue against the conventional wisdom that the major source of the threat of future pandemics is spillover of pathogens from animals to people. And few would argue against the need for tight safety precautions at laboratories doing research on potentially deadly microbes.
So, why has a debate about issues that are largely of academic interest become so vitriolic? So politicized? What is the debate really about? Several observations suggest that it is not a scientific debate at all and is not really driven by concern over the origins of the pandemic.
Most mass media have reported the lab-leak debate as a bitter debate between two groups of scientists. In fact, the debate is asymmetrical. On the one side, the overwhelming weight of opinion among virologists, epidemiologists, evolutionary biologists, and other scientists with experience and expertise in studying epidemic viral diseases is that COVID reached humans directly from an animal host or hosts. Although a few such experts have supported the lab-leak side, the most prominent proponents of a lab-leak origin are journalists, economists and public policy experts, politicians, postdoctoral fellows, and more-senior scientists who lack relevant expertise or experience.
While direct evidence for either a lab leak or an animal origin remains lacking, the lab-leak side has relied much more heavily on purely circumstantial evidence (e.g., pointing out that the Wuhan lab and the initial outbreak of COVID-19 occurred in the same city) and speculation (e.g., arguing that certain aspects of the molecular structure of the virus “could only” have arisen through experimental manipulation, not through evolution). Their claim that the failure to identify the animal that was the source of the virus discredits the animal-origin hypothesis is spurious—again, it can take decades to identify the exact source of a disease.
Even the concept of a lab leak has been a shifting target: Initially, the concern was often that the source of SARS-CoV-2 was bioweapon research. Later, accusations flew that SARS-CoV-2 had been created by laboratory manipulation of less dangerous viruses. Other voices raised suspicions about sloppy handling of virus-bearing bats or carelessness with lab samples or problems arising in the course of testing a vaccine.
The animal-origin side, by contrast, has predominately relied on the standard tools of epidemiology and virology. These include genomic evidence, spatial and temporal and epidemiological analysis of cases of COVID-19, the existence of closely related wildlife coronaviruses, the presence of species of animals in the Wuhan wet market known to carry related coronaviruses, and studies of potential evolutionary sequences that could have led to the emergence of SARS-CoV-2 in the wild.
At times, the debate has gotten nasty, with each side accusing the other of bad faith. Early on, it was common for the liberal media to call the belief that SARS-CoV-2 was a human-made virus created in the lab a conspiracy theory. Today, with most scientists dismissing that position, it is lab-leak proponents who proclaim that scientists who support the animal-origin position are guilty of a cover-up. These researchers have been “weaponizing their expertise to avoid potential accountability for their colleagues killing millions of people,” lab-leak advocate Alex Washburne has said. (Washburne is a mathematical biologist working at a private consulting firm.) They “colluded in telling the media that [the lab-leak hypothesis] was a debunked conspiracy theory,” journalist and businessman Matt Ridley wrote in the Telegraph. The National Institutes of Health’s Dr. Anthony Fauci “colluded” with Facebook CEO Mark Zuckerberg to shut down talk about the origins of COVID, the state attorneys general of Missouri and Louisiana charged in a federal court.
The debate has also been politicized right from the start. Blaming China for the pandemic has become a project of the Republican Party. As COVID-19 was shutting down businesses and schools in the U.S., then-President Trump and Secretary of State Mike Pompeo were already insisting on China’s responsibility, despite the absence of evidence. Whether intentionally or not, the attacks on scientists and on China served the purpose of diverting attention from the Trump administration’s failure to effectively address the pandemic and, later, bashing the Biden administration for not being tough enough on China.
As more and more has become known about the virus, most scientists have concluded that the evidence points more and more strongly toward the animal-spillover theory. Republican politicians have continued to tout the lab-leak hypothesis, however. In mid-2021, for instance, top Republican lawmakers held a forum to demand hearings on “the public health question of our time”: how the virus arose. “China lied and Americans died,” said Elise Stefanik, then the No. 3 Republican in the House of Representatives. More than a year later, in October 2022, Sen. Richard Burr, the top Republican on the Senate Health Committee, released a staff report arguing that the pandemic was “more likely than not” caused by a laboratory incident in China. And, keeping a campaign promise, no sooner had the Republicans taken control of the House in January 2023 than they commissioned a new probe into the origins of COVID-19.
The lab-leak theory has an appeal that transcends scientific evidence. People like stories that explain things that happen to us. With bad events especially, we look for a simple story with a clear villain to blame. Both the lab-leak theory and the continuing debate itself provide such stories. In fact, humans have long blamed pandemics on others.
Pandemics create uncertainty and fear, which easily turn to speculation and suspicion. Jews were blamed for the Black Death, which wiped out 40 percent of the population of Europe in the 14th century. The 1918 influenza pandemic, AIDS, SARS-1, the 2009 H1N1 influenza pandemic, and the Zika virus all caused substantial parts of the population to believe that the diseases were somehow human-made. Why should COVID-19 be any different?
In the case of COVID-19, the primary potential villain identified by lab-leak proponents, of course, is China. The lab-leak hypothesis fits into the needs of the growing number of Americans who are hostile to China and receptive to opportunities for China-bashing. Conservative New York Times columnist Ross Douthat gleefully noted in 2021 that if it could be proved that the virus had originated in a lab leak, it would show that the whole pandemic “was basically [the Chinese] Chernobyl except their incompetence and cover-up sickened not just one of their own cities but also the entire globe.”
The lab-leak debate also plays into another narrative commonly pushed by the right: hostility to science and “experts” and to the elites that support them. The NIH’s Fauci has been an especially frequent target of right-wing enmity. Other scientists who have discussed COVID-19 in the media have become targets of harassment, intimidation, and threats from people who believe that the pandemic is a hoax, that the virus was created intentionally to cause harm, or that vaccines are dangerous. Of 510 scientists who published articles dealing with COVID-19 and who responded to a 2022 Science Magazine survey, 38 percent reported being the target of attacks ranging from insults to death threats.
Despite most qualified scientists finding the evidence for an animal origin compelling, the American public has increasingly bought into the lab-leak hypothesis. In March 2020, at the very beginning of the pandemic, only 28 percent of Americans believed that the virus had been made in a Chinese lab. By the end of 2021, the number had risen to 72 percent. As with early warnings of climate change and as with efforts to get widespread compliance with public health measures to mitigate the pandemic, “listen to the science” seems not to have worked.
If the debate is not really about how to lessen the likelihood of a future pandemic, what gives the lab-leak theory oxygen? What feeds the continued insistence on maintaining the debate? It goes deeper than a simple desire to cast blame on China. Another part of the explanation may lie in where people get information. The reports of proponents of an animal origin are, by and large, published in peer-reviewed journals such as Science, Cell, the Lancet, and Nature, which are read mainly by other scientists. While a few peer-reviewed articles by lab-leak proponents have appeared, the most widely discussed presentations of their views are in more-accessible mass-market books, lay periodicals such as Vanity Fair, the Wall Street Journal, and the Bulletin of the Atomic Scientists, widely reported statements by politicians and their staff, and non-peer-reviewed “preprint” journals whose conclusions have been reported uncritically by the press.
People also generally prefer simple, straightforward stories that give them a sense of control over complex ones filled with ambiguity and complexity that foster a sense of helplessness. The lab-leak story is simple. Short version: Someone in a lab in China doing research on deadly viruses screwed up. The actions to take are clear: Blame China. Demand reparations. Tighten up regulation of laboratories doing research on disease-causing microbes. Bar gain-of-function research that alters viruses to make them more deadly.
The animal-origin story is much more complex: What animals are natural reservoirs for the virus? Why didn’t those animals die before passing the disease on to us? What other kinds of animals did they transmit it to? How did the animal disease evolve to become deadly to humans? How did people come into contact with sick animals? Why are diseases that start in animals occurring more often and spreading more rapidly than in the past? If the disease were already in animals, why didn’t people catch it sooner? Why are there reports of people who may have been ill with what was later called COVID-19, several months before the pandemic emerged? Why haven’t we found animals in the Wuhan wet market with the virus? And so forth.
The answers to these questions are not simple. They lie in the complex interactions among climate change, deforestation, the growing trade in wildlife and wildlife products, factory farming, urbanization and the expansion of slums worldwide, and globalization. At best, the actions needed to address these are complex, prolonged, expensive, and disruptive to existing social and economic institutions and processes. At worst, we are left feeling helpless.
Finally, we seek explanations of events that are consistent with what we already believe about other things and with what our family, friends, and neighbors believe. Political convictions and allegiances can also bias information processing and what we believe. Conservatives are likely to agree with Republican politicians who have strongly argued for the lab-leak hypothesis and for hostility to “experts,” while liberals are likely to agree with Democratic politicians, who are more likely to be concerned with issues such as global warming, loss of biodiversity, and the ethics of factory farming.
The lab-leak debate was never a scientific debate about the sources of future pandemics. What it tells us is not where COVID-19 came from, but the limits of science in informing public debate. Whether facts and theories are believed, by scientists and laypeople alike, depends not only on the “facts” (people even disagree on what constitutes a fact) but also on who is making the argument, to whom it is addressed, and how it is made visible.
Scientific debates are not simply arguments among objective scientists as they sift facts and seek the best explanations. They are messy, often quarrelsome, and political all the way down. As the late philosopher and historian of science Bruno Latour has reminded us, “Facts remain robust only when they are supported by a common culture, by institutions that can be trusted, by a more or less decent public life, by more or less reliable media.”
We’ve been here before. Recall the climate change debate: Was the earth actually getting warmer? If so, were humans really the cause? Although almost all scientists knew the answers to these questions years ago, fossil-fuel interests portrayed it as a real scientific “debate.” The result was a 30-year delay in acting on the causes of global warming, a delay that is already having disastrous consequences.
Whatever the conscious intentions of the proponents of a lab leak as the source of COVID-19, their arguments and their insistence on playing and replaying the debate have become dangerous. They shift responsibility for the U.S.’ disastrous handling of the pandemic away from the failures of our political system, our politicians, and our health and public health systems and to a geopolitical rival. They are a partisan political cudgel, diverting attention from the real sources of danger of future pandemics and delaying action on what could be an existential threat to humans.