Newly released private communications indicate that leading scientists, who publicly dismissed the theory that COVID-19 originated from a lab leak, privately acknowledged the possibility that the virus could have escaped from a laboratory. These messages, revealed by U.S. Senator Rand Paul and published by Homeland Security, suggest that doubts emerged as early as July 2020, just months after a highly influential paper co-authored by these scientists was published in Nature Medicine.
The March 2020 paper asserted that "we do not believe that any type of laboratory-based scenario is plausible," instead suggesting the pandemic likely resulted from an animal spillover event. However, private messages show Kristian Andersen, a lead author from the Scripps Institute, expressing uncertainty.
"At the end of the day, we really don't have any hard evidence one way or the other – and especially given some of the recent evidence, we also can't rule out that somebody actually put it in there," Andersen wrote on the messaging platform Slack. "Our paper was pretty strong in saying there's no way, but I have less confidence in that statement at this stage."
The theory that COVID-19 originated from the Wuhan Institute of Virology (WIV), located approximately eight miles from the initial outbreak site, has been a point of contention since early in the pandemic. U.S. President Donald Trump claimed in May 2020 that he had seen evidence of a lab origin, and in February 2023, former FBI Director Christopher Wray stated it had "most likely" originated in a "Chinese government-controlled lab." China has consistently rejected these allegations, labeling them as political manipulation.
Further communications revealed concerns among the authors regarding the extent of coronavirus research at the WIV. While the Nature Medicine paper broadly stated that such research occurred "across the world," Andersen later noted that this was inaccurate, and the work had "exclusively been going on at WIV."
Andersen also indicated a shift in his personal assessment. "Given the data we had seen at the time of our writing, I was highly skewed towards 'natural'," he wrote. "But with some of this new data (plus stuff I didn't know previously), I'm moving much more towards the middle (again)."
Additional messages indicated awareness that Dr. Shi Zhengli, a leading bat coronavirus researcher at WIV, had expressed fears that the pandemic could have resulted from a lab accident. Professor Edward Holmes, another co-author, wrote in March 2021 that Shi had told them she was "very worried about a lab escape" and that internal audits found nothing, which Holmes found troubling as it suggested a "likely explanation."
Senator Paul commented on the released messages via X, stating, "Behind closed doors, the scientists who authored the Proximal Origin paper privately questioned their own conclusions. Publicly, however, they shamed, attacked, and censored those who raised legitimate questions – all in the name of damage control. We deserve accountability for every effort to keep the public in the dark."