An expert in tracing the origins of viral epidemics claims to have identified the very first-known case of COVID-19: in a vendor at the Huanan Seafood Market in Wuhan, China. In a March report, a WHO team that had visited China in January concluded the first-known case appeared in a 41-year-old Wuhan accountant unconnected to the market, who the team was told developed symptoms on Dec. 8, reports the New York Times. It identified a second case in a market vendor, who developed symptoms on Dec. 11. But according to evolutionary virologist Michael Worobey of the University of Arizona, who pens a peer-reviewed article published Thursday in Science, the vendor's case actually emerged first.
Worobey reviewed interviews and medical records showing the accountant with the last name Chen said he first developed symptoms around Dec. 16. But the date that was communicated to WHO researchers came not from Chen but from doctors at a hospital not involved in Chen's care (he was hospitalized on Dec. 22). The potential source of the Dec. 8 date: Chen had dental surgery that day, per the Washington Post, and his medical records described a fever and a prescription for antibiotics on Dec. 9. It's enough to convince at least one member of the WHO team, disease ecologist Peter Daszak, that there was a mix-up, with the earlier date wrongly noted. "The mistake lies there," he says.
The WHO said it would look into the discrepancy in the date of symptom onset when it was highlighted by the Post in July. A spokesperson now tells the Times that it's "difficult to comment" on the first-known case because the WHO team had limited access to data. But Worobey says seafood vendor Wei Guixian—who described feeling sick on Dec. 10 or Dec. 11—was likely first. The scientist says his conclusion fits with data showing more than half of early cases were in people with direct links to the market. "It becomes almost impossible to explain that pattern if that epidemic didn't start there," he tells the Post.
Notably, Worobey was among a group of scientists to call for an investigation into all possible sources of the virus, including a lab leak, back in May. But "it becomes almost absurd, in my mind, to imagine that this virus started at the Wuhan Institute of Virology, and almost immediately that person went to one of the few places that sold raccoon dogs and other animals that were implicated" in the first SARS epidemic of 2002-03, he tells the Post. The debate still rages, though. Virologist Jesse Bloom tells the Times that there is not enough data at this time to show that the market was anything beyond "a super-spreading event." (Read more coronavirus stories.)