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G.O.P. Senator’s Report on Covid Origins Suggests Lab Leak, but Offers Little New Evidence

The report, signed by Senator Richard Burr, foreshadows a new wave of political wrangling over Covid’s origins if Republicans gain control of the House or Senate.

Security personnel outside the Wuhan Institute of Virology during a visit by the W.H.O. to investigate the origins of the coronavirus, in Wuhan, China, in February 2021.
Credit...Thomas Peter/Reuters

The top Republican on the Senate health committee said in a report on Thursday that the coronavirus pandemic was most likely caused by a laboratory incident in China. The report offered little new evidence, however, and was disputed by many scientists, including those whose research suggests that the outbreak originated instead at a live animal market.

The report, released by Senator Richard M. Burr, Republican of North Carolina, grew out of a joint inquiry with the committee’s Democratic chairwoman that proponents of the effort hoped would add a measure of bipartisan credibility to a highly charged debate.

But the findings published on Thursday, while interim, bore only Mr. Burr’s signature. And in relying largely on existing public evidence, rather than new or classified information, the report came as something of a letdown even to those who supported its conclusions.

“One can only conclude from the circumstances that they met an impasse,” said Richard Ebright, a molecular biologist at Rutgers University, referring to his disappointment that Republican and Democratic staff members working on the inquiry have not yet released a more complete, bipartisan report.

Dr. Ebright, who was interviewed by the report’s authors, said he supported the argument that evidence pointed to a laboratory origin. But the only new element, he said, appeared to be questions raised about how China could have developed a vaccine so quickly, which he did not find persuasive. Otherwise, he said, “there was no information in the report that has not been publicly presented in the media and discussed in the media previously.”

It is not clear why the interim report was only signed by Mr. Burr or when a final report might be published. Mr. Burr and the chairwoman, Senator Patty Murray, Democrat of Washington, said in statements that the health committee’s bipartisan review of how Covid first emerged would continue.

The Huanan Seafood Wholesale Market in Wuhan, China, attracted interest as the potential source of the pandemic early on. By the spring of 2020, senior Trump administration officials were promoting the idea that the virus had instead escaped from the Wuhan Institute of Virology, a large laboratory that studied bats and was situated about eight miles away, across the Yangtze River. China now largely insists that the virus originated abroad.

Scientists are bracing for a new wave of political wrangling over the origins of the virus in the coming year, especially if Republican backers of the lab leak theory take control of committees in the House or Senate.

Several researchers who have studied the beginnings of the pandemic, though, described the Burr report as a step backward in the effort to understand that period.

The report highlights what it describes as holes in the theory of a natural spillover of the virus from animals to humans, including the continuing failure to identify any animal at the Wuhan market that spread the virus to humans. It argues that those gaps, combined with what it describes as problems with safety protocols at the Wuhan Institute of Virology, indicate that the pandemic “was, more likely than not, the result of a research-related incident.”


But scientists said that Chinese officials had made it virtually impossible to identify an infected animal by closing and disinfecting the Wuhan market before relevant live animals could be sampled. And for all the concern about research at the Wuhan lab, no evidence has been produced to show that the institute stored any virus in its collections that could have become the virus causing Covid-19, with or without engineering.

“This was an embarrassingly bad use of taxpayer money and resources,” said Angela Rasmussen, a virologist at the Vaccine and Infectious Disease Organization at the University of Saskatchewan in Canada, who co-authored one of a pair of papers published in Science in July pointing to the Wuhan market as the origin of the pandemic. “It’s very clear they had preordained conclusions they wanted to come to.”

Dr. Rasmussen said that aides to Mr. Burr and to Ms. Murray asked her how to conduct such an investigation in mid-2021 as they were beginning their research. But she said they never followed up.

The Burr report said that it drew on interviews with several dozen experts. But 12 scientists who contributed to the Science articles published in July said in interviews or emails that they had not been questioned by the health committee’s staff members.

One of the studies found that the home addresses of early Covid patients centered on the Huanan market in a pattern that could not be explained by chance. The second suggested that the virus spilled over into people working or shopping there on two separate occasions.

House Republicans had earlier released a report that said the pandemic likely began with an accidental release from the Wuhan lab.

Some scientists said on Thursday that the latest report reflected a deep uncertainty about where the pandemic originated.

“There is no ‘smoking gun’ one way or the other, and we may never get it,” said Sergei Pond, a virologist at Temple University. He added that the “nontrivial possibility” that it might have emerged from a lab should inform decisions about lab safety and oversight of dangerous research.

Others who have lately remained open to different theories about the virus’s origin nevertheless said on Thursday that they were puzzled about some of the claims in Mr. Burr’s report.

Dr. W. Ian Lipkin, a virologist at the Mailman School of Public Health at Columbia University, said that it was not clear that the virus came from the live animal market in Wuhan. But he said the inability to find an infected animal did not prove anything.

“There’s no way to access them,” Dr. Lipkin said. “They killed all the animals in these markets.”

The report also claimed that the virus’s ability to spread quickly from person to person at the start of the pandemic was evidence counting against an origin in wildlife. But an author of the study cited to back up that claim said it was wrong.

“Many viruses jump directly from animals to humans without the need for adaptation,” said that study’s author, Raina Plowright, a virologist at Cornell University.

A correction was made on 
Oct. 28, 2022

An earlier version of this article misidentified the affiliation of a virologist, Raina Plowright. It is Cornell University, not the University of Montana.

How we handle corrections

Benjamin Mueller is a health and science reporter. Previously, he covered the coronavirus pandemic as a correspondent in London and the police in New York. More about Benjamin Mueller

Carl Zimmer writes the “Matter” column. He is the author of fourteen books, including “Life's Edge: The Search For What It Means To Be Alive.” More about Carl Zimmer

A version of this article appears in print on  , Section A, Page 22 of the New York edition with the headline: Republican’s Report on Virus Suggests It Was Lab Leak, but Without Much Proof. Order Reprints | Today’s Paper | Subscribe