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Since regaining power, the Trump administration has repeatedly claimed with false certainty that the COVID-19 pandemic originated in a lab.
In late January, White House Press Secretary Karoline Leavitt said that a lab leak is “the confirmable truth.”
In mid-April, covid.gov and covidtests.gov, websites the government previously used to educate the public about the disease and allow people to place orders for free tests, redirected to a new, splashy White House webpage that declared a lab leak the “true origins” of COVID-19.
This month, in explaining a nearly $18 billion proposed cut to the National Institutes of Health, President Donald Trump’s budget request for the next fiscal year stated that a lab origin “is now confirmed by several intelligence agencies.”
But there has been no such confirmation. In late January, the CIA joined the FBI and the Department of Energy in concluding a lab origin is “most likely.” But those determinations were each made with low or moderate confidence, and the agencies don’t agree on the source lab. As many as five other intelligence bodies lean toward a natural origin or are undecided.
Joel Wertheim, a professor of medicine at the University of California San Diego who has published research on how the pandemic began, told us the website is “untrue.”
As we’ve explained before, the origin of the coronavirus, SARS-CoV-2, is unknown. Multiple lines of scientific evidence, however, point to a natural origin, with the virus spilling over into humans from animals through the illegal wildlife trade in China. That is similar to what has happened in the past, including in the early 2000s with SARS, when a similar coronavirus caused a respiratory disease outbreak that began in China.
“There’s overwhelming scientific evidence that COVID emerged from an animal market in Wuhan, which was miles away from a virology lab,” Gigi Gronvall, a senior scholar at the Johns Hopkins Center for Health Security and an associate professor at the Bloomberg School of Public Health, told us.
While for many scientists the evidence for a natural origin is convincing, no intermediate animal has been found harboring a virus highly similar to SARS-CoV-2, so the theory remains unproved. Some scientists are uncertain and some favor a lab leak.
It is unclear on what specific information the intelligence agencies are basing their determinations. Scientists who have studied the origins question closely have encouraged more transparency, but note that the scientific aspect of the investigation is highly technical. Michael Worobey, an expert in virus evolution at the University of Arizona who is an author of several of the major COVID-19 origins papers, told the Associated Press in 2023 that he doubted the individuals making the assessments “have the scientific expertise … to really understand the most important evidence.”
Other Trump officials have also recently endorsed a lab leak, even if they do not always frame it as definitive. Food and Drug Administration Commissioner Dr. Marty Makary, for example, said the pandemic was “probably the result of some scientists messing with Mother Nature” and that a lab leak “is now the leading theory among scientists.” In congressional testimony on May 15, Health and Human Services Secretary Robert F. Kennedy Jr. stated that multiple agencies “have all agreed that NIH research almost certainly led to the pandemic.”
Those statements are unsupported or contradicted by available evidence. As we said, there is neither a consensus nor strong confidence among the different U.S. intelligence agencies that there was a lab leak. But one thing nearly all did agree on, according to a declassified 2023 report, is that the coronavirus “was not genetically engineered.”
Scientists have also previously told us that it’s virtually impossible that SARS-CoV-2 was engineered.
“SARS-CoV-2 shows no evidence of being manipulated or passage[d] in a laboratory prior to its emergence,” Wertheim said. “The scientific literature is emphatic on this point, with broad consensus even among scientists who disagree regarding the particulars of the location and timing of the emergence of SARS-CoV-2.”
There is also little to suggest that scientists now prefer the lab leak theory, as Makary said. In 2023, 156 scientists penned a commentary in the Journal of Virology that said that the zoonosis hypothesis, or the idea that the virus spilled over to humans from an animal, “has the strongest supporting evidence,” while lab leak scenarios have “no compelling evidence.” Subsequently, another 120 scientists with the Australasian Virology Society wrote to the journal to agree. A 2024 survey by the Global Catastrophic Risk Institute also found scientists overwhelmingly favored a natural origin.
Wertheim objected to Makary’s characterization, noting that the “peer-reviewed literature is dominated by articles supporting a zoonotic origin” while lab leak papers “are rare, fringe, and mutually incompatible with each other.”
Claims that the NIH funded work that led to the pandemic have been promoted for years. But as we’ve repeatedly explained, the small amount of NIH grant money that went to the Wuhan Institute of Virology funded experiments using viruses that are very different from SARS-CoV-2 and could not have led to the creation of the coronavirus.
When asked what the Trump administration’s certainty about a lab leak was based on, and why it discounted the published research that supports a natural origin, White House spokesman Kush Desai pointed to the Intelligence Community assessments.
“Multiple intelligence agency assessments have now substantiated that COVID-19 originated from a lab leak – an idea that the mainstream media once completely wrote off as a lunatic fringe conspiracy theory,” he told us in an email. “While the media continues to decimate what’s left of its record-low credibility, the Trump administration remains committed to transparency for the American people.”
HHS did not respond to a similar inquiry about Kennedy’s and Makary’s statements.
Factually Inaccurate Website
In addition to incorrectly presenting a lab leak as an established fact, the White House webpage lists five numbered statements purporting to bolster its case. Each is either incorrect or misleading. We’ll address them one by one (the italic emphasis in each statement is the White House’s).
“The virus possesses a biological characteristic that is not found in nature.” False. This is presumably a reference to SARS-CoV-2’s furin cleavage site, or FCS, a short sequence that helps the virus enter cells. Much of the speculation about the coronavirus being lab-generated has stemmed from this site, since no other SARS-related coronavirus is known to have a FCS. But as we’ve explained before, the sites do exist in other, more distant coronaviruses. As a result, while unusual, the FCS is not inherently suspicious.
“It is most certainly found in nature,” Wertheim said.
“Data shows that all COVID-19 cases stem from a single introduction into humans. This runs contrary to previous pandemics where there were multiple spillover events.” Data do not show this. A Science paper published in 2022, which analyzed genomic data from early COVID-19 cases, concluded that there were likely at least two spillovers from animals to humans.
Wertheim, who was a senior author of that paper, said he took “particular umbrage” with this claim because “it was an uphill battle to convince other scientists that not only did multiple introductions occur, but that multiple introductions would be expected.”
“Wuhan is home to China’s foremost SARS research lab, which has a history of conducting gain-of-function research (gene altering and organism supercharging) at inadequate biosafety levels.” Wuhan is home to the Wuhan Institute of Virology, which worked on bat coronaviruses and genetically manipulated some of them. But there’s no evidence the WIV worked on any viruses remotely similar enough to have given rise to SARS-CoV-2 (whether the experiments qualified as gain-of-function is also subject to debate).
The intense focus on such issues is in many ways irrelevant, since the scientific literature is “unified” in concluding that the coronavirus “was not subject to manipulation or ‘gain-of-function’ experiments prior to its emergence,” Wertheim said.
The presence of the institute can seem too unlikely to be a coincidence, but as we’ve explained before, Wuhan is a hub for the wildlife trade and is home to some 11 million people. The population density is key, since a spillover in rural China would likely have simply fizzled out, Wertheim said.
Much is often made about the long distance between Wuhan and where SARS-CoV-2’s closest ancestors were identified in bats. But the coronavirus behind the 2002 SARS epidemic, which everyone agrees was a natural spillover, also traveled a similar distance to Guangdong. A paper published in May in Cell, co-authored by Wertheim, documents the similarities between the two cases and implicates travel via the wildlife trade for both.
“Wuhan Institute of Virology (WIV) researchers were sick with COVID-like symptoms in the fall of 2019, months before COVID-19 was discovered at the wet market.” Rumors of sick WIV workers — with various details shifting over time — have circulated since 2020, as we’ve explained before. But the U.S. Intelligence Community has already said that the information is not relevant to the question of how the pandemic began.
Because “the researchers’ symptoms could have been caused by a number of diseases and some of the symptoms were not consistent with COVID-19,” the 2023 declassified report explains, the IC “continues to assess that this information neither supports nor refutes either hypothesis of the pandemic’s origins.”
“By nearly all measures of science, if there was evidence of a natural origin it would have already surfaced. But it hasn’t.” There is evidence of a natural origin; it’s just not conclusive. The lack of an intermediate animal — which might prove a natural origin, and is presumably what this is referencing — does not mean that the coronavirus must have originated in a lab.
As we have written, the wet market where the first COVID-19 cases were recognized was quickly shut down. While some animal testing occurred early on, it was primarily in species that would not be expected to be the animals that transferred the virus to humans. China has also demonstrated little to no interest in looking any further for an intermediate animal, insisting instead that the virus came from abroad, including from the U.S.
“Evidence of zoonosis has surfaced,” Wertheim said, noting that there is now genetic evidence that animals known to transmit SARS-like viruses were in the same part of the market where the first cases were found, with remnants of SARS-CoV-2 where the animals were kept. “This evidence is exactly what you would expect to find had a zoonotic virus emerged.”
That’s in addition to the epidemiology data, which show the earliest COVID-19 cases cluster around the market, even those without a known connection to the market.
Again, all of this doesn’t formally rule out a lab leak. But it’s incorrect to claim that the lack of an intermediate animal is strong evidence of a lab leak.
Clarification, May 23: We clarified that Wertheim was a senior author, and not just a co-author, of one of the scientific papers.
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