Scientists have revealed that there is “compelling evidence” that Wuhan’s Huanan seafood and wildlife market is at the centre of the Covid-19 outbreak.

Two peer-reviewed studies published on Tuesday, July 26, 2022, re-examined information from the initial outbreak in the Chinese city. One of the studies showed that the earliest known cases were clustered around that market. The other uses genetic information to track the timing of the outbreak.

It suggested that there were two variants introduced into humans in November or early December 2019. Together, the researchers said that this evidence paints a picture that Sars-Cov-2 was present in live mammals that were sold at Huanan market in late 2019. They said it was transmitted into people who were working or shopping there in two separate “spillover events”, where a human contracted the virus from an animal.

One of the researchers involved, Virologist, Professor David Robertson, from the University of Glasgow, revealed to the media that he hoped the studies would “correct the false record that the virus came from a lab”.

Pandemic Epicentre

Two years of scientific effort to understand the virus that causes Covid-19 have provided these researchers with a more informed perspective.

This enabled them to address a key conundrum in the earliest patient data, which disclosed that out of hundreds of people who were hospitalised with Covid-19 in Wuhan, only about 50 had a direct, traceable link to the market. “That was really puzzling that most cases could not be linked to the market,” said Professor Robertson said.

“But knowing what we know about the virus now, it’s exactly what we would expect – because many people only get very mildly ill, so they would be out in the community transmitting the virus to others and the severe cases would be hard to link to each other.”
Virologist, Professor David Robertson

This Covid-19 case-mapping research found that a large percentage of early patients with no known connection to the market, which means they neither worked nor shopped there, did turn out to live near it.

As a result, this supported the idea that the market was the epicentre of the epidemic, says Professor Michael Worobey, who is the lead author and Biologist from the University of Arizona, with sellers getting infected first and setting off a “chain of infections among community members in the surrounding area”.

“In a city covering more than 3,000 sq miles (7,770 sq km), the area with the highest probability of containing the home of someone who had one of the earliest Covid-19 cases in the world was an area of a few city blocks, with the Huanan market smack dab inside it.”
Professor Michael Worobey, Lead author and Biologist

That study also zoomed in on the market itself. The scientists created a map of the samples, which were swabs of fluid from drains and on market stalls, which tested positive for the virus. “Most of the positive samples clustered around the south-western side of the market,” Professor Robertson explained.

“And that’s the location where we report species like raccoon dogs being sold. So we have confirmation of animals we now know are susceptible [to Sars-Cov-2, the virus that causes Covid-19] were sold there in late 2019.”
Virologist, Professor David Robertson