New lines of inquiry into how the Covid-19 outbreak began have been opened with the publication of Chinese research, including analysis of samples taken more than three years ago from the Huanan seafood and wildlife market in the city of Wuhan.
The research links the virus with animals sold in the market. It reveals that swabs that tested positive for the virus also contained genetic material from wild animals.
The BBC points out that the market has long been a focal point in the search for the origin of the coronavirus, but that this is the first peer-reviewed study of biological evidence gathered from the market back in 2020.
The Chinese research team’s paper showed that some samples – collected from areas where wildlife was being sold – had tested positive for the virus.
Their analysis also showed that animals now known to be susceptible to the virus, particularly raccoon dogs, were being sold alive in those locations.
However, BBC science correspondent Victoria Gill says the Chinese researchers have pointed out that their discoveries fall short of definitive proof of how the outbreak started, as the ‘environmental samples cannot prove that the animals were infected’.
The possibility remains, the researchers add, that the virus was brought into the market by an infected person, rather than an animal.
University of Glasgow virologist Prof David Robertson – who has been involved in the genetic investigation into the origin of SARS-CoV-2 since it emerged in 2020 – is quoted by the BBC as saying: ‘The most important thing is that this very important dataset is now published and available for others to work on’.
He added: ‘When you bring [this body of evidence] together with the fact that the early Covid-19 cases in Wuhan are linked to the market, it’s strong evidence that this is where a spillover from an animal in the market occurred.’
[ Photo: SCMP / Roy Issa]