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Biotechnology and health

Newly revealed coronavirus data has reignited a debate over the virus’s origins

Samples kept from view since they were collected in 2020 highlight the possible role of raccoon dogs. That kicked off plenty of drama this week.

Raccoon Dog, Nyctereutes procyonoides in tall grass
Getty Images

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This week, coronavirus has been back in the news in a big way. We’ve seen the resurgence of a debate that has been swirling since the start of the pandemic—where did the virus that causes covid-19 come from?

For the most part, scientists have maintained that the virus probably jumped from an animal to a human at the Huanan Seafood Market in Wuhan at some point in late 2019. But some claim that the virus leaped from humans to animals, rather than the other way around. And many continue to claim that the virus somehow leaked from a nearby laboratory that was studying coronaviruses in bats.

Data collected in 2020—and kept from public view since then—potentially adds weight to the animal theory. It highlights a potential suspect: the raccoon dog. But exactly how much weight it adds depends on who you ask. New analyses of the data have only reignited the debate, and stirred up some serious drama.

The current ruckus starts with a study shared by Chinese scientists back in February 2022. In a preprint (a scientific paper that has not yet been peer-reviewed or published in a journal), George Gao of the Chinese Center for Disease Control and Prevention (CCDC) and his colleagues described how they collected and analyzed 1,380 samples from the Huanan Seafood Market.

These samples were collected between January and March 2020, just after the market was closed. At the time, the team wrote that they only found coronavirus in samples alongside genetic material from people.

There were a lot of animals on sale at this market, which sold more than just seafood. The Gao paper features a long list, including chickens, ducks, geese, pheasants, doves, deer, badgers, rabbits, bamboo rats, porcupines, hedgehogs, crocodiles, snakes, and salamanders. And that list is not exhaustive—there are reports of other animals being traded there, including raccoon dogs. We’ll come back to them later.

But Gao and his colleagues reported that they didn’t find the coronavirus in any of the 18 species of animal they looked at. They suggested that it was humans who most likely brought the virus to the market, which ended up being the first known epicenter of the outbreak.

Fast-forward to March 2023. On March 4, Florence Débarre, an evolutionary biologist at Sorbonne University in Paris, spotted some data that had been uploaded to GISAID, a website that allows researchers to share genetic data to help them study and track viruses that cause infectious diseases. The data appeared to have been uploaded in June 2022. It seemed to have been collected by Gao and his colleagues for their February 2022 study, although it had not been included in the actual paper.

When Débarre and her colleagues analyzed this data, they found evidence that some of the samples Gao’s team collected that were positive for the coronavirus had been collected from areas that housed a range of animals, including raccoon dogs. Their findings were covered in a report by The Atlantic. Since then, Débarre and her colleagues have posted a report detailing their findings on the scientific repository Zenodo.

“This finding was a really big deal, not because it proves the presence of an infected animal (it doesn’t). But it does put animals—raccoon dogs and other susceptible species—into the exact location at the market with the virus. And not with humans,” Angela Rasmussen, a virologist at the University of Saskatchewan in Canada and a coauthor of the report, tweeted on March 21.

Raccoon dogs are of special interest because we now know that they are at risk of being infected with the virus and spreading it. But the data doesn’t confirm that raccoon dogs in the market had the virus. Even if they did, it doesn’t mean that they were the animals responsible for passing the virus to humans. So what does it mean?

If you ask a proponent of the lab leak theory, it means nothing. There is no new conclusive evidence that the virus jumped to humans at the Huanan Seafood Market, or that raccoon dogs were involved.

But if you ask one of the many scientists who believe that this marketplace jump from animals is the most likely origin of the coronavirus outbreak in people, they might tell you that this strengthens their case. For them, it’s another nail in the coffin for the lab leak theory, because it offers yet more compelling evidence that susceptible animals were exposed to the virus, at the very least.

There’s more drama to this story. Débarre and her colleagues say they told Gao’s team their findings on March 10. The next day, Gao’s team’s data disappeared from GISAID, and Débarre’s team took their findings to the World Health Organization. The WHO convened two meetings to discuss both teams’ results with the Scientific Advisory Group for the Origins of Novel Pathogens (SAGO).

“Although this does not provide conclusive evidence as to the intermediate host or origins of the virus, the data provide further evidence of the presence of susceptible animals at the market that may have been a source of human infections,” SAGO said in a statement on March 18.

But many are concerned that researchers in China have been hiding their data. The preprint shared in 2022 made no mention of raccoon dogs, but the data posted on GISAID, as well as photographic evidence, suggests that these animals were present at the market before it was closed. Gao’s team’s data “could have—and should have—been shared three years ago,” WHO director general Tedros Adhanom Ghebreyesus said at a media briefing on March 17. “We continue to call on China to be transparent in sharing data, and to conduct the necessary investigations and share the results.”

Débarre’s team are among many scientists publicly urging the CCDC to share all their data. Given that the samples were collected at the start of 2020, “an unreasonable amount of time” has passed already, Débarre and her colleagues write. Gao and his colleagues are apparently working on a paper that will be submitted for publication in a Nature journal. So perhaps we’ll learn more then …

In the meantime, there’s yet more drama! On March 21, Débarre tweeted that she’d had her access to GISAID revoked. This is probably because she and her colleagues shared their own analysis of the Chinese team’s results. According to a statement released by GISAID that same day, the Chinese researchers were preparing their own paper based on that data (the Nature one, presumably). Any other scientists using that data for their own publication would essentially be unfairly “scooping” the Chinese team. Débarre’s access was restored the following day, and Débarre has asked for an apology from “people who questioned our integrity.”

“This isn’t about ‘scooping.’ It’s about the world’s right to know how the pandemic that has profoundly disrupted all our lives began,” Rasmussen tweeted.

The debate over the origins of the virus behind covid-19 continues to rage. US federal agencies can’t agree on where they stand. And while the majority of scientists support the animal theory, many are open to the idea the virus escaped from a lab.

My money is on an animal jump. Not only is keeping animals caged and in close contact inhumane, but it provides the perfect environment for the spread of disease. Trapping wild animals and encroaching on their habitats is known to pose the risk that a disease will jump between species. Even if the coronavirus outbreak did have some other origin, I hope we won’t lose sight of the importance of maintaining wildlife habitats and banning the trade of wild animals.

You can readand listen to!more from Tech Review’s archive:

My colleague Antonio Regalado investigated the origins of the coronavirus behind covid-19 in his brilliant five-part podcast series “Curious Coincidence."

Last year, Jane Qiu spoke to Shi Zhengli of the Wuhan Institute of Virology. Shi, sometimes nicknamed “China’s bat woman,” has long been at the center of the controversy over the lab leak theory.

Michael Worobey of the University of Arizona, who performed the recent analysis of the CCDC data with Débarre, signed a letter asking for more investigation into the lab leak theory in May 2021. He now believes that a spillover of the virus from animals at the Huanan Seafood market was almost certainly behind the origin of the pandemic, as Qiu reported in 2021.

Antonio had the inside scoop on how Pfizer developed Paxlovid, an antiviral drug that was found to reduce the chance of a serious case of covid by 89%.

Since then, others have explored whether anti-aging drugs might also help us treat covid, as I reported last year.

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