The Lancet on July 5 published a statement reasserting that there is no "scientifically validated evidence" to suggest COVID-19 escaped from a lab, signed mostly by the same team of scientists who dismissed the lab-leak hypothesis in a February 2020 statement. But the new statement is missing three signatories from the original one, including William Karesh, who has ties to the Wuhan Institute of Virology.
Karesh is the executive vice president for health policy at EcoHealth Alliance, the group that was funding gain-of-function research at the Wuhan lab with grants from the National Institutes for Health. EcoHealth's president, Peter Daszak, organized the original statement, whose signatories included Karesh, Peter Palese of the Icahn School of Medicine, and Bernard Roizman of the University of Chicago. Those three signatures are all absent from the new statement, though Daszak signed both.
Asked whether he'd changed his mind about the likelihood of a lab leak, Palese replied: "NO COMMENT!" Karesh and Roizman did not respond to inquiries.
The missing signatures reflect the widening cracks in the scientific consensus about COVID-19's origins. Once dismissed as a far-right conspiracy theory, the lab-leak hypothesis became mainstream in May when former New York Times science reporter Nicholas Wade defended it at length in the Bulletin of the Atomic Scientists. Following Wade's piece, Nobel Prize-winning virologist David Baltimore said a lab leak was a serious hypothesis he "wouldn't rule out," while other biologists maintained that the scientific evidence supporting it was very weak.
The debate only grew more intense in June with the publication of Anthony Fauci's emails, which seemed to indicate that he and other government scientists had taken the lab leak seriously behind closed doors. In one correspondence, a team of virologists told Fauci that the genome of the virus was "inconsistent with the expectations of evolutionary theory." In another, Fauci instructed his assistant to read a paper about the Wuhan Institute of Virology's gain-of-function research. "[We'll] try to determine if we have any distant ties to this work abroad," the assistant replied.
The recent Lancet statement responds directly to these developments. "We believe the strongest clue from new, credible, and peer-reviewed evidence in the scientific literature is that the virus evolved in nature," the authors write. "Suggestions of a laboratory-leak source of the pandemic remain without scientifically validated evidence that directly supports it in peer-reviewed scientific journals."
They also write that "it is time to turn down the heat of the rhetoric and turn up the light of scientific inquiry," saying "allegations and conjecture are of no help."
The February 2020 statement, which did not disclose its authors' ties to the Wuhan lab, contained several allegations of its own. "We stand together to strongly condemn conspiracy theories suggesting that COVID-19 does not have a natural origin," the statement read. "Conspiracy theories do nothing but create fear, rumours, and prejudice that jeopardise our global collaboration in the fight against this virus."