Nicholas Wade:

The argument is ingenious. Its fatal flaw lies in assuming that the non-market cases chosen for study were selected at random by the Chinese authorities. In fact, as Chan has noted, one of the authorities’ criteria was closeness to the market. The spatial pattern of non-market cases reflects this selection bias, not a hidden chain of infection to the market. “Since their assumption of no ascertainment bias is most likely incorrect, their analysis is therefore also meaningless,” Chan says.

Unlike most journalists, science writers seldom consider the motives of their sources. Few or none remarked on Andersen’s deep personal interest in the result he was trying to prove. He and his colleagues concluded on January 31, 2020, that the Covid virus did not have a natural origin. But Francis Collins, then director of the National Institutes of Health, immediately decreed this view to be a conspiracy theory that will do “great potential harm to science and international harmony.” Not to mention to his own reputation and that of his lieutenant Anthony Fauci. Both have long advocated for gain-of-function research—enhancing the infectivity of natural viruses—and they funded such research involving bat viruses at the Wuhan Institute of Technology.

No scientist wishes to get on the wrong side of NIH administrators, the major funders of biomedical research. If Collins said the lab leak was a conspiracy theory, why then, so it must be. A mere four days later, Andersen changed his mind and derided lab leak as a conspiracy theory. No one in his group has provided a convincing explanation for this 180-degree reversal. Andersen’s new paper, if true, would go a long way to justifying his otherwise unsupported second take on the issue.