The deadly Covid-19 pandemic may have originated in raccoon dogs from the Wuhan market in China, according to an international team of virus experts.

More than two years after the pandemic, the origins of Covid-19 remain unclear. It has been a political and scientific debate with scientists and politicians globally contending that the Coronavirus jumped into people from bats, or have been leaked from a laboratory.

The new study, yet to be published, and led by experts including from Universities of Arizona, Utah and Sydney and from the Scripps Research Institute is based on genetic data drawn from swabs taken from in and around the Huanan Seafood Wholesale Market starting in January 2020, the New York Times reported.

Although the Chinese authorities had shut down the market after being linked to the outbreak of Covid pandemic, and the animals cleared out, the researchers got the samples from swabbing walls, floors, metal cages and carts that are used for transporting animal cages.

The results showed that large amounts of genetic material were a match for the raccoon dog, the NYT report said.

Raccoon dogs are related to foxes and are known to be able to transmit the Coronavirus.

“We were able to figure out relatively quickly that at least in one of these samples, there was a lot of raccoon dog nucleic acid, along with virus nucleic acid,” Stephen Goldstein, a virologist at the University of Utah who worked on the new analysis, was quoted as saying.

(Nucleic acids are the chemical building blocks that carry genetic information.)

However, the team noted that “jumbling together of genetic material from the virus and the animal does not prove that a raccoon dog itself was infected. And even if a raccoon dog had been infected, it would not be clear that the animal had spread the virus to people.”

“Another animal could have passed the virus to people, or someone infected with the virus could have spread the virus to a raccoon dog,” they said.

But the scientists stated that their “analysis did establish that raccoon dogs deposited genetic signatures in the same place where genetic material from the virus was left,” the NYT report said.

That evidence was consistent with a scenario in which the virus had spilled into humans from a wild animal.

“We don’t have an infected animal, and we can’t prove definitively there was an infected animal at that stall,” Goldstein said.

But genetic material from the virus is stable enough, he said, adding that it is not clear when exactly it was deposited at the market.

“But,” he said, “given that the animals that were present in the market were not sampled at the time, this is as good as we can hope to get.”

The experts also pointed out the presence of genetic material from other animals and from humans in the samples.