Amy Maxmen in Nature:
Scientists have released three studies that reveal intriguing new clues about how the COVID-19 pandemic started. Two of the reports trace the outbreak back to a massive market that sold live animals, among other goods, in Wuhan, China1,2, and a third suggests that the coronavirus SARS-CoV-2 spilled over from animals — possibly those sold at the market — to humans at least twice in November or December 20193. Posted on 25 and 26 February, all three are preprints, and so have not been published in a peer-reviewed journal.
These analyses add weight to original suspicions that the pandemic began at the Huanan Seafood Wholesale Market, which many of the people who were infected earliest with SARS-CoV-2 had visited. The preprints contain genetic analyses of coronavirus samples collected from the market and from people infected in December 2019 and January 2020, as well as geolocation analyses connecting many of the samples to a section of the market where live animals were sold. Taken together, these lines of evidence point towards the market as the source of the outbreak — a situation akin to that seen in the epidemic of severe acute respiratory syndrome (SARS) in 2002–04, for which animal markets were found to be ground zero — says Kristian Andersen, a virologist at the Scripps Research Institute in La Jolla, California, and an author on two of the reports. “This is extremely strong evidence,” he says.
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