Evidence points to Raccoon Dogs as a potential COVID-19 source

In:In yet another twist in the ongoing search for the origins of COVID-19, an international team of researchers stumbled upon new genetic material that had been entered into a public scientific database and then abruptly deleted.

As first reported AtlanticIn early March, evolutionary biologist Florence Debard of France’s National Center for Scientific Research searched the GISAID public database, where scientists upload the genetic sequences of the pathogens they study. On the site, he found sequences from samples collected in January 2020 from the Huanan Seafood Wholesale Market in Wuhan, China, shortly after the market was closed due to fears that the COVID-19 virus may have originated from animals sold there.

Debar, along with researchers from the US and Australia, later looked at the genetic sequences and found that it could be traced back to a stall cart that one of the team’s scientists remembered from a visit to the market back in 2014. that New York Times. At the time, the raccoon dogs were kept on a cart with their cages stacked on top of the cages that housed the birds, a device that infectious disease experts know can promote the spread of viruses from species to species. In 2020, the sample taken from the cart also contained SARS-CoV-2.

In February 2022, Chinese officials released the results of swabs taken from air, surfaces and animals on the market in 2020, although not all genetic sequences from those samples had been uploaded to GISAID. That report found no virus in 18 animal species sampled, although the virus was common in environmental samples such as air and surfaces, suggesting that humans carry the virus and potentially spread it in the marketplace.

The scientific and political communities have long been divided over whether SARS-CoV-2 originated in animals and spread to humans, or whether the virus was created, intentionally or accidentally, by researchers at the nearby Wuhan Institute of Virology and then spread. is on animals. and people around the world. In the most recent intelligence report on the subject, the US Department of Energy leaned toward the lab leak hypothesis, but classified its conclusion as “low confidence.” Four other U.S. government groups and the U.S. National Intelligence Council determined that the virus likely originated in animals and reached humans, but their estimates were also low to moderate confidence, leaving open the question of how COVID started. – the 19th.

New specimens discovered by Debar may help provide some answers. But shortly after he and other scientists contacted the Chinese team that wrote the original report, the genetic sequences disappeared from GISAID.

During a press conference on March 17, Maria Van Kerkhove, the World Health Organization’s technical chief for COVID-19, called on China to make the deleted data available to scientists. “The big problem at the moment is that this data exists and that it is not readily available to the international community,” he said. The World Health Organization suggested in its first investigation that the virus likely spread from bats to humans, although earlier this year the organization delayed the next phase of its planned analysis, citing difficulties in accessing data from Chinese health authorities. “We have to look at all the data we need to evaluate each of them [hypotheses] to say: this happened, this did not happen.”

Although recent genetic evidence has identified animal and virus genes in the same location, it still does not identify the genetic sequence of an infected animal or an animal that shows evidence of virus infection. But the fact that DNA from raccoon dogs and genetic material from the virus existed in such close proximity means that it’s possible that SARS-CoV-2 infected raccoon dogs and then jumped to market-going humans.

The sequence Debar discovered suggests there is more data from those initial tests on the market that Chinese authorities have not fully disclosed or analyzed. That incompleteness leaves the mystery of where COVID-19 originated.

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