Newly released genetic data gathered from a live food market in Wuhan has linked Covid-19 with raccoon dogs, adding weight to the theory that infected animals sold at the site started the coronavirus pandemic, researchers involved in the work say.
Swabs collected from stalls at the Huanan seafood market in the two months after it was shut down on 1 January 2020 were previously found to contain both Covid and human DNA. When the findings were published last year, Chinese researchers stated that the samples contained no animal DNA.
That conclusion has now been overturned by an international team of scientists. Their analysis of gene sequences posted by the Chinese team to the scientific database Gisaid found that some of the Covid-positive samples were rich in DNA from raccoon dogs. Traces of DNA belonging to other mammals, including civets, were also present in Covid-positive samples.
The discovery does not prove that raccoon dogs or other animals infected with Covid triggered the pandemic, but scientists presenting the work to an expert group at the
World Health Organization on Tuesday believe it makes that more likely.
“The data does point even further to a market origin,” Prof Kristian Andersen, an evolutionary biologist at Scripps Research in La Jolla, California, told
Science magazine. Andersen attended a meeting of the WHO’s scientific advisory group for the origins of novel pathogens and is working on the data.
