Almost as soon as the COVID-19 pandemic went global in early 2020, a public debate over its origins erupted. No one doubted then, or doubts now, that the SARS-CoV-2 virus originated in China before spreading all over the world. Yet since the first humans were infected, the mainstream scientific narrative has been that the SARS-CoV-2 virus was passed from an animal to humans at a wet market.
This view has not gone unchallenged: A small group of scientists and other public commentators — some, but not all, with political agendas — theorize that the virus originated in the wild before being captured and experimented upon in a biolab like the nearby Wuhan Institute of Virology, from where it then leaked. Even after an article in Science Magazine last summer seemed to reaffirm the wet market theory, the lab leak notion has held on to its adherents. Major publications — including New York Magazine, the New Yorker and the MIT Technology Review — published stories on it.
"SARS-CoV-2 is the only one of the more than 200 known SARS related coronaviruses — the only one in its category — that contains a furin cleavage site. This is a feature that is more easily explained by a lab origin."
Now the so-called lab leak hypothesis has been supercharged by a series of external events: First the Department of Energy shifted its stance on the matter, announcing a "low confidence" level that the virus originated with a lab leak. Then on Tuesday, FBI Director Christopher Wray told Fox News that the pandemic "most likely" began due to a lab leak in Wuhan. Previously this week, the Department of Energy called lab leak the "most likely" origin of the COVID-19 pandemic as well, according to a classified intelligence report.
According to experts who spoke with Salon, these developments certainly mark an important shift in the public discussion about the pandemic.
To a layperson, the lab leak hypothesis has an obvious appeal due to its simplicity: it lays clear who is to blame for the global pandemic that cost millions of lives. Yet a simple narrative is not necessarily a true one, and researchers who work in microbiology, virology or public health remain relatively skeptical of the lab leak hypothesis — with a few notable exceptions.
Initially, many experts with whom Salon spoke said they had not seen data that would hint at the lab leak hypothesis.
"According to press reports, Director Wray stated 'there's not a whole lot of details I can share that aren't classified,'" Russell Medford, PhD, Chair and CEO, Covanos, Inc. and Immediate Past Chair, Center for Global Health Innovation, told Salon by email. "I cannot comment on his overall assertion as to the likelihood of a lab leak without seeing the underlying data."
"I do not know the basis for the FDA/[Department of Energy] decision, since there continues to be no data supporting a lab leak except proximity to the [Wuhan Institute of Virology] (and it is not very close — just within the same city)," Stanley Perlman, MD, Ph.D., a professor of microbiology and immunology at the University of Iowa, observed.
Dr. Susan Weiss, a University of Pennsylvania professor who has studied coronaviruses for decades, felt similarly. "My overall thought is that there has been so much hype about lab leak but I have not see any data to support this assertion," she said. "Scientists need data to be persuaded."
By contrast, Rutgers University chemistry and chemical biology professor Dr. Richard H. Ebright told Salon that he believes the virus leaked from a lab. Ebright has been outspoken about this assertion: he testified before the Senate to this effect, and issued a long Twitter thread on the subject.
Ebright also elaborated on his reasons during a phone interview. As he pointed out, scientists know for sure that the pandemic was caused by a bat carrying a SARS-related coronavirus, and that it emerged in the Chinese city of Wuhan. Ebright expressed doubt that wild bats carrying SARS-CoV-2-related viruses lived close enough to Wuhan to cause a natural outbreak there, and noted that Wuhan is home to "the world's largest research program on bat-SARS-related coronaviruses." Researchers from the Wuhan Institute of Virology previously published numerous papers on these bat coronaviruses, including a 2017 paper published in PLoS Pathogens titled "Discovery of a rich gene pool of bat SARS-related coronaviruses provides new insights into the origin of SARS coronavirus."
On top of that, Ebright pointed out that as early as 2015, scientists and diplomats voiced concern that the Wuhan lab posed a high risk of a laboratory accident, as the Washington Post previously reported.
"My overall thought is that there has been so much hype about lab leak but I have not see any data to support this assertion. Scientists need data to be persuaded."
Ebright noted that the Wuhan Institute of Virology had previously worked on SARS-related coronaviruses that could combine the spike gene of one coronavirus with genetic information from a different coronavirus. Intriguingly, that research was actually funded partially by the U.S. National Institutes of Health, which provided a grant to EcoHealth Alliance with a "subaward to the Wuhan Institute of Virology in Wuhan, China."
"In order to study animal coronaviruses circulating in nature, the investigators replaced the spike protein from a well-characterized bat coronavirus, WIV1-CoV, with the spike protein of animal coronaviruses recently discovered in bats in China," an NIH website explains.
Ebright elaborated on this study, saying that "the resulting laboratory-generated virus was efficiently infected and replicated in human airway cells, and exhibited 10,000 times enhanced viral growth and four times enhanced lethality in mice engineered to display human receptors on their airway cells."
Additional research into SARS-related coronaviruses soon followed.
"In 2017 to 2019, the Wuhan Institute of Virology constructed and characterized novel SARS-related coronaviruses using biosafety level two," Ebright told Salon; this is corroborated by other reports, including from MIT Technology Review. "That's a biosafety level that is inadequate for, indeed is recklessly inadequate for, work with enhanced potential pandemic pathogens, and that would be unable to contain a virus that has the transmission properties of SARS-CoV-2."
Ebright is also persuaded by the fact that the SARS-CoV-2 virus has many of the "exact properties" described in grant proposals from both that institute and from US government agencies like DARPA and NIH.
Such research, in which a virus is made more infectious in the lab, is known as "gain of function" research.
"SARS-CoV-2 is the only one of the more than 200 known SARS related coronaviruses — the only one in its category — that contains a furin cleavage site," Ebright explained as one example. "This is a feature that is more easily explained by a lab origin." He concluded by accusing the Wuhan Institute of Virology "and its collaborators at EcoHealth Alliance" of having "withheld information, misrepresented facts, and obstructed investigation."
The furin cleavage site has become a fixation among both the lab leak believers and detractors. Furin, an enzyme that humans and some animals possess, is implicated in the ability of the virus to replicate efficiently and easily. In a previous interview, Perlman disagreed with Ebright on the importance of the furin cleavage site to the virus' replication abilities, saying that its presence wasn't a smoking gun that humans had tampered with the virus' genetics.
The interest in manipulating the genetics of coronaviruses is not necessarily a sinister endeavor reserved for bioweapons makers: American and European virologists frequently experiment with dangerous viruses that can infect humans, and have for decades. Often, researchers in the lab attempt to make viruses more infectious with the hopes of understanding how they mutate and thus staving off future pandemics. Such research, in which a virus is made more infectious in the lab, is known as "gain of function" research.
Even if SARS-CoV-2 was tinkered with in the lab in Wuhan, it could just as easily have leaked from a U.S. lab doing comparable work. The National Institutes of Health was engaged in funding gain-of-function research for decades, with a three-year pause in funding from 2014 to 2017. When it was lifted in December 2017, the NIH director gave a statement praising such seemingly dangerous research.
"Today, the National Institutes of Health announced that it is lifting a funding pause dating back to October 2014 on gain-of-function (GOF) experiments involving influenza, SARS, and MERS viruses," NIH director Francis S. Collins wrote at the time. "GOF research is important in helping us identify, understand, and develop strategies and effective countermeasures against rapidly evolving pathogens that pose a threat to public health."
For his part, Medford believes that the data on the SARS-CoV-2 virus points in the exact opposite direction: that it started in bats and mutated as it spread through humans, with no stop-over in a lab.
"The sequence of the originally reported SARS-CoV-2 virus that causes COVID-19 is closely related to some bat coronaviruses, and SARS-CoV-2 has since evolved the many mutations that have affected transmissibility, virulence and vaccine responsiveness," Medford wrote to Salon. "There is no evidence that the virus was genetically engineered. To my knowledge, there is also no evidence that definitively links the current pandemic to a laboratory release of the SARS-CoV-2 virus."
Perlman was more blunt.
"There is a lack of evidence that the virus was ever present in any laboratory in Wuhan," Perlman told Salon. "The best data are for an animal source, but even here there are gaps. The virus was never been isolated from an animal in China or elsewhere and it has not been isolated from bats even though bats are the most likely source of the virus," as the genome of the virus reveals that it gestated in bats for a long while before mutating.
