A new report into the origins of Covid-19 appears to have drawn a conclusion as to where exactly the virus which has killed at least 5.1 million people worldwide started.
The report published in journal Science by Dr Micheal Worobey, an expert on the genome of viruses at the University of Arizona, states the first person to fall sick with coronavirus was a seafood vendor at Huanan Market in Wuhan, China on December 11, 2019.
“Notably, she reported knowledge of several possible Covid-19 cases in clinics and hospitals that were near Huanan Market from 11 December, and Huanan Market patients were hospitalised at Union Hospital as early as 10 December,” he wrote.
It is not clear if this is the same seafood merchant, a 57-year-old woman named Wei Guixian, who was at one stage theorised to be patient zero.
Findings contradict WHO's earlier report
His finding contradicts a World Health Organisation report from earlier in the year that the first known Covid-19 case was a 41-year-old accountant, “who lived 30 km south of Huanan Market and had no connection to it”.
The accountant fell ill on December 8. But Dr Worobey found he did not have coronavirus at the time but had actually an ailment related to a dental issue. He did, however, fall sick with coronavirus more than a week later on December 16.
Dr Worobey wrote the man "was infected through community transmission after the virus had begun spreading from Huanan Market”.
A map, used in the article, shows that while many cases were believed to have no connection to the market they all appear to be heavily concentrated around it.
Dr Worobey added the man had travelled north of the market before his symptoms began, which occurred after multiple cases came out of the market which sold “live mammals susceptible to coronaviruses, including raccoon dogs”.
Dr Worobey used media reports, including from Chinese publication The Paper, hospital records, audio recordings and other research papers to determine his findings.
Other theories on Covid-19's origins
His findings are at odds with other theories about the origins of Covid-19 including that it leaked out of a Chinese lab. This lab leakage theory was supported at stages by the belief the accountant, who was said to have no link to the market, was the first case of coronavirus.
Gao Fu, director of China’s Center for Disease Control and Prevention, told China Global Television Network in May last year that the market was “one of the victims” in disputing presumptions it was where the virus started.
Dominic Dwyer, an Australian scientist who was among a World Health Organisation team of researchers sent to China to investigate the origins of the virus, wrote in an article for The Conversation in February the market “was more of an amplifying event rather than necessarily a true ground zero”.
Experts have also suggested the market theory was biased and scientists were actively looking at it specifically as being the first exposure site. Dr Worobey acknowledged he was aware of this bias when conducting his research.
A WHO spokesperson told The New Scientist the team did meet with early cases of Covid-19 in China “but those were not epidemiological interviews collecting health data that would put them in the timeline”.
The spokesperson added that those interviews were conducted by Chinese authorities.
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