Scientists now believe that the cause of the global spread of COVID-19 may have been raccoon dogs that carried the virus and were sold at a Chinese market.

A new study from Oxford University published in Science suggests that raccoon dogs, which were sold for their fur and meat at the Huanan Seafood Market in Wuhan, China, could have passed on the virus from bats to humans, scientists of the study said.

While the theory is not fully confirmed as the animals were not tested at the very start of the pandemic, scientists have found detection of COVID-19 in samples tested from cages and carts used to transport the raccoon dogs in late 2019.

Chris Newman, a biologist, ecologist, and research associate with Oxford University, and co-author of the study, told USA Today, “As far as the virologists are concerned, looking at the evolutionary strain of the virus itself, it's perfectly reasonable that (SARS-CoV-2) evolved in a bat and then spread through the raccoon dog as the primary intermediary.”

Sold at wet markets, raccoon dogs are kept in conditions that can promote the spread of disease, as bacteria and viruses pass through feces and urine. The animals are then slaughtered at purchase to provide the freshest meat possible, Newman told the news outlet. Wet markets in China have since been closed, but many are still in existence in other countries.

According to Newman, the spread of COVID from raccoon dogs is completely plausible as the animals don’t show signs of illness from the virus they are carrying.

Many people have speculated that COVID-19 originated from a lab in Wuhan, which the study’s co-author Dr. Angela Rasmussen, a virologist, disputed on Twitter, saying the all data suggested that the seafood market in Wuhan is the origination point.

While the study is unable to conclusively prove that raccoon dogs are the originating source of COVID-19, Rasmussen said that “environmental samples point to the animals,” adding in a tweet, “Zoonotic spillover at Huanan is the only emergence scenario that accounts for all these threads of evidence.”

Raccoon dogs are nocturnal like raccoons, and Thomas Müller, a veterinarian, who has also studied the possibility of these animals as a COVID-19 originating source, told USA Today, “They are not aggressive at all. You would hardly see them in nature.”

To date, about 40 million raccoon dogs are bred in China for their fur, about 99% of the animal’s global population, Müller said.

Raccoon dogs have also been illegal to sell in China, but it was a regulation that was not widely enforced prior to the start of the pandemic.

Wuhan's markets are bustling once again
Wuhan's markets are bustling once again AFP / Hector RETAMAL