New data seems to reconfirm Wuhan market as source of Covid-19, discounts lab leak theory
By Syraat Al Mustaqeem
A seafood market in Wuhan, China, has been identified as the likely epicentre of the Covid-19 pandemic, new studies show. The Huanan Seafood Market in Wuhan was highlighted as an early hotbed of the virus, according to two peer-reviewed studies published Tuesday.
This follows recommendations from the World Health Organisation (WHO) in June to continue research into possible sources of the virus – including a lab leak.
Although this geographical conclusion, which was released in pre-prints in February, was labelled “controversial”, one study showed that Covid-19 cases from as early as December 2019 were linked to the market.
Scientists used mapping tools and reports on social media to provide an environmental analysis. The results pointed towards the virus being present in livestock sold at the market – but the study noted that the “exact circumstances remain obscure”.
Co-author Kristian Andersen said that “the clustering is very, very specific”. Andersen, a Scripps Research professor in the Department of Immunology and Microbiology, added: “I was quite convinced of the lab leak myself, until we dove into this very carefully. Based on data and analysis I’ve done over the last decade on many other viruses, I’ve convinced myself that actually the data points to this particular market.”
Michael Worobey, department head of Ecology and Evolutionary Biology at the University of Arizona, endorsed the account and said the link was “not a mirage”. He added: “It’s just not plausible that this virus was introduced any other way than through the wildlife trade.”
Close quarter contact increased the likelihood of germs spreading, the study said. It went on: “Of the initial 41 people hospitalised with unknown pneumonia by January 2 2020, 27 (66 per cent) had direct exposure to the Huanan Wholesale Seafood Market. “However, the observation that the preponderance of early cases were linked to the Huanan market does not establish that the pandemic originated there.”
Two separate viruses were detected in the mammals being sold on the western side of the market. The second study focused on cross-contamination between animals to humans.
Researchers took a molecular approach, which emphasised the distinction between virus ‘A’ and ‘B’.
Results suggested that version ‘B’ was the first to be transmitted to humans who had direct contact to the market around mid-November 2019, while lineage ‘A’ spread in those who lived close to it.
Credit: The Evening Standard