New studies published in the peer-reviewed journal Science are offering new evidence that the Huanan food market in Wuhan, China, served as the “early epicenter” of the COVID-19 pandemic.
The scientists who wrote the study concluded that SARS-CoV-2, the coronavirus that causes COVID-19, said a statement from the American Association for the Advancement of Science (AAAS), which published the journal Science is, possibly present in living mammals. It was sold at Huanan Seafood Wholesale Market in late 2019 before infecting people.
They say future studies should focus on where the wild mammals sold in Huanan came from, which could help prevent the risk of future pandemics.
“Despite the observation that the majority of the earliest known COVID-19 cases – marked by hospitals in Wuhan in December 2019 – were linked to the Huanan market, this did not establish activities in the Huanan market as the trigger of the pandemic,” AAAS statement it is said.
The study by an expert group prepared by the World Health Organization said in June that more research is needed to determine how COVID-19 first began, including the possibility of a laboratory accident.
Preprint, or non-peer-reviewed, versions of the studies were released in February.
In one of them, researchers used mapping tools to estimate the longitudes and latitudes of more than 150 of the first reported cases since December 2019, including those with no notable direct link to the market .
They say the highest density of cases centered around the market in Wuhan.
The researchers also mapped cases for January and February 2020 using a channel on the Chinese social media app Weibo, which was designed for people who had COVID-19 and sought medical help.
Using this data, they found market-borne cases in other parts of central Wuhan.
They say live mammals susceptible to SARS-CoV-2, including red foxes, hog badgers and common raccoon dogs, were also sold live on the market in late 2019.
The researchers note that while they were able to retrieve location data for most of the December 2019 COVID-19 cases, accurate longitude and latitude were not available for all of them.
There is no direct evidence of an intermediate animal being infected with SARS-CoV-2 early, either at the Huanan market or at any other location in its supply chain, such as a farm, they say.
In the second study, researchers looked at the genetic diversity of early SARS-CoV-2, identifying two lineages, A and B.
The scientists say that only lineage B was found in the 11 sequenced genomes of people directly linked to the Huanan market.
People with the lineage A genome, meanwhile, had no known contact with the market, but they lived or lived near.
Scientists believe both lineages were circulating in non-human mammals, with lineage B first appearing in humans in mid-November 2019, followed by lineage A within days or weeks.
As in the previous study, the researchers say they lack direct evidence of a virus, which is closely related to SARS-CoV-2, present in non-human mammals in the market or its supply chain.