The mysterious origin of the COVID-19 pandemic, like so many aspects of the response to it, has created deep divides along party lines in the United States. Today, the Republican minority staff of a bipartisan Senate committee set up to probe the origin of SARS-CoV-2 issued an “interim report” arguing for the narrative that the virus entered humans because of a lab-related incident and not a natural jump from animals to humans. Many virologists and evolutionary biologists who have studied the origins of outbreaks dismiss the lab-leak hypothesis, but other scientists have complained that the possibility was too readily downplayed, and it has become increasingly popular among conservative media outlets and some Republican politicians.
“Based on the analysis of the publicly available information, it appears reasonable to conclude that the COVID-19 pandemic was, more likely than not, the result of a research-related incident,” the minority staff concludes in its 35-page report. That conclusion stands in sharp contrast to those of other panels, including from the World Health Organization and U.S. intelligence agencies, which have deemed a zoonotic jump more likely or remained neutral given the lack of direct evidence on the origin of the virus.
Senator Richard Burr (R–NC), the ranking member of the Senate’s Committee on Health, Education, Labor, and Pensions (HELP), wrote in a forward to the report that the minority oversight staff spent 15 months reviewing scientific studies and interviewing experts. The goal, Burr wrote, was “to provide a clearer picture of what we know, so far, about the origins of SARS-CoV-2 so that we can continue to work together to be better prepared to respond to future public health threats.”
Michael Worobey, an evolutionary biologist at the University of Arizona who has co-authored scientific reports examining data from the early days of the pandemic that provide some of the strongest support for a jump from animals to humans, speculates that the timing of the report’s release could be “a cynical effort to try to win Republican votes” in the upcoming midterm congressional and state elections. Or, Worobey says, “it could just be a bunch of staffers with no ability to understand the science who stumbled across a bunch of misinformation and disinformation-filled tweets.” (“Senator Burr felt enough compelling, open-source information had been gathered during staff's comprehensive review of the facts that an interim report was appropriate,” a senior aide to the minority staff told Science.)
Worobey’s origin papers, which argue for a zoonotic jump at a market in Wuhan, China, come in for significant criticism in the report, to which he responded today in a Twitter thread to two reporters who sent him questions based on a draft of the report they apparently obtained in advance of its release. “These comments are either intentionally misleading or the result of honest misunderstandings, perhaps due to a failure to read our papers, which address these issues in great detail,” Worobey wrote. (Two of his most closely scrutinized papers were recently published by Science.)
The report recounts many details discussed at length in the media and the scientific literature since SARS-CoV-2 emerged in Wuhan in late December 2019. It focuses intense attention on the Wuhan Institute of Virology (WIV), which has a long record of studying bat coronaviruses, some of which have similarities to SARS-CoV-2. Those who argue for a lab-related release often suggest that WIV scientists either conducted experiments that created the virus or obtained it in the wild. They suspect it then escaped somehow, causing the first cluster of cases at the Wuhan market.
No direct evidence has surfaced that WIV had a version of SARS-CoV-2 in its lab or did such genetic engineering, but supporters of the lab leak scenario cite circumstantial evidence and suspicious patterns, which the report recounts in detail. It emphasizes the lack of transparency from the Chinese government and putative biosecurity lapses at the WIV labs with equipment such as air ducts.
As for the natural spillover theory, the report repeatedly emphasizes that no direct evidence exists that an animal sold at the Wuhan market or farmed in China was infected with a virus similar to SARS-CoV-2 prior to the pandemic. “While the absence of evidence is not itself evidence, the lack of corroborating evidence … three years into the pandemic, is highly problematic,” it reads.
One section of the minority staff report focuses on a detail that has not received much attention to date: that Chinese scientists tested the first experimental COVID-19 vaccines in humans a month earlier than similar candidates developed through the U.S. government’s crash program Operation Warp Speed. The Chinese vaccines used a different technology from the first U.S. vaccines, but all depended on the genetic sequence of SARS-CoV-2. The speed of the Chinese vaccine effort leads the report to ask whether Chinese researchers had access to that sequence prior to the rest of the world. The report, however, doesn’t address whether other factors could explain the rapid pace, such as the urgency of the outbreak in China or different regulatory environments.
Senator Patty Murray (D–WA), who chairs the Senate HELP committee, issued a statement today that did not comment on the report’s content or the timing of the release. “The HELP Committee is continuing bipartisan work on this oversight report,” Murray’s statement said.
