The debate on the true origin of the Covid-19 pandemic is still open. Did it originate from a leak in a Chinese lab? Is it a product of nature? A new study, carried out by French researchers, reinforces the theory that everything started with the transmission of the virus from animals to humans, as most scientists defend.
The new clue supports a link between SARS-Cov-2 and the sale of raccoon dogs. Also known as tanuki, these carnivorous mammals are close relatives of foxes and originate from eastern China.
The worst pandemic in a century would therefore be caused by an infected wild animal that was sold illegally in the Wuhan market, the epicenter of the pandemic. A possibility that China was reluctant to admit.
The new data is based on samples that Chinese researchers collected between January and March 2020 in the Wuhan market where it is suspected that it all started. Samples were taken from the soil, the sewage, from the cages where there were live animals, from the machines used to handle them… The virus that generates Covid was sought in order to sequence it. But with the usual scant transparency, China did not allow other scientific teams access to the virus sequences for repeat analysis.
China withheld information
However, some of these sequences have only recently been deposited in international data banks. And now Florence Débarre, a researcher at the French Scientific Research Center (CNRS), has found them almost by chance. From her study, Débarre concludes that these new sequences are more compatible with a zoonosis as the origin of the pandemic.
A raccoon-dog, similar to the raccoon and fox
The mix of genetic material found from the virus and from the mammal does not prove that the raccoon dog itself was infected. And even if a raccoon dog had been infected, it wouldn’t be clear that the animal was responsible for the jump to humans. Another animal could have passed the virus to people, or someone infected with the virus could have passed it to a raccoon dog.
The data is also being mined by evolutionary biologists at the University of Arizona. But they have already been submitted to the World Health Organization, to the SAGO group that studies the origins of new pathogens.
What the French scientist’s finding does show is that China hid information and wanted to divert attention from the Wuhan market as the origin of the pandemic. The then director of the Chinese CDC, George Gao, stated that “there was nothing new” in the information they had withdrawn, only the certainty that animals were being trafficked illegally -including mammals-, which is why they decided to close the market for Wuhan.
A fact that China denied at first, until a scientific publication acknowledged that they had evidence of the existence of live mammals on the market for at least two years before the outbreak of the pandemic. In 2014, University of Sydney virologist Edward Holmes photographed a raccoon dog for sale at the Huanan market in the city of Wuhan.
Despite the refusal, the French researchers insist on the need for the genetic information to be published again “as soon as possible” in the face of Gao’s refusal, whose research suggested that the origin of the pandemic came from outside the market and that Wuhan it only served as an amplifier for the spread of the virus.
