A new analysis of samples taken from a market in Wuhan, China, at the start of the pandemic is the strongest evidence yet that the Covid-19 virus jumped from animals to humans, some researchers say.
The samples found evidence of the new coronavirus as well as genetic material from various animals – including raccoons susceptible to the disease, according to a report published Monday on the Zenodo.org Open Science website. Take the example of the South China wholesale seafood market.
reported that in some samples there was more animal genetic material than human genetic material, suggesting that the animals may have been infected with SARS-CoV-2. Like much of the research that has been published rapidly during the pandemic, it has not yet been approved by the scientific community.
The effort to finalize the report comes after last week’s early discovery sparked strong interest and a flurry of media coverage. The World Health Organization has called on China to fully share the genetic data analyzed by the researchers, which briefly appeared in the database before being deleted. Because for some outside experts, the whole situation is just worrying.
David Relman, professor of microbiology and immunology at Stanford University, said: “I am very concerned that we are jumping to something that is incomplete and cannot be verified.” “I think we need to take a deep breath and stick to any important issue. This particular issue has due process and science.
Relman said that was true on both sides of the Covid origins debate. He has long argued that both theories – a laboratory accident or a natural spill – should be investigated with equal rigor.
The report is a review of The final chapter in a major response to how the pandemic began. President Joe Biden on Monday signed a bill to declassify information about the origins of Covid-19. The US intelligence community remains divided over its findings, with the FBI and Department of Energy concluding that Covid-19 may have originated from a lab accident.
The latest report further complicates the situation.
WHO Director-General Tedros Adhanom Ghebreyesus told a press conference on Friday: “These data do not provide a clear answer to the question of how the pandemic started, but every piece of data is important. and allows us to get closer to it. provides answers.”
Scientists generated their report after samples uploaded by Chinese scientists briefly appeared in the open-access genomics database GISAID. An international team of scientists writing papers supporting the hypothesis that Covid-19 originated in the southern Chinese market has been researching what they call “priceless” sequence data for more than a year.
“This is the first time we’ve been able to identify the genetic fingerprint of the virus and a potential intermediate host in exactly the same location,” said University of Utah virologist Stephen Goldstein, who participated in the study. analysis, in an interview. “That’s a perfect match for what you see in zoonotic spread events.”
No conclusive evidence
Samples show DNA from raccoons – distant relatives of foxes, sometimes sold in wet markets in China (like the one in Wuhan) – linked to first cases of Covid 2019 SARS coronavirus After the outbreak of SARS in 2002, a natural infection was found in raccoon dogs in another market in China. Studies have shown that these animals are also capable of shedding the virus.
Seeing the samples showing raccoon DNA was “one of the most incredible moments of my career,” Goldstein said.
DNA from several other animal species known to be susceptible to SARS-CoV-2, including Malaysian porcupines and bamboo rats, was also found in the samples, the World Organization said on Saturday. health in a press release.
According to the scientists who conducted the analysis, this strongly supports the idea that animal-to-human transmission caused the pandemic.
“The presence of viruses and potentially host genetic material in the marketplace is exactly what the zoonotic origin hypothesis would expect,” said Joel Wertheim, associate professor at the University of California, San Diego, who participated in the virus analysis. . to taste.
Others are less convinced.
Jumping to conclusions with very little information initially available “is not the way to do careful, thoughtful scientific research,” Relman said.
Access to the data analyzed by the researchers is essential, as it “will enable a more informed discussion of the strength of the new evidence”, wrote François Balloux, director of the Institute of Genetics at University College London, on Twitter.
The existence of data is no secret. Disease detectives who arrived from Beijing at the start of the pandemic ordered the collection of environmental samples from sewers and other market surfaces. “All current evidence points to the illegal sale of wild animals,” George Gao, director of the Chinese Center for Disease Control and Prevention, and colleagues wrote in
the agency’s January 2020 weekly report.
All but two of the positive samples came from part of the west wing of the market, where a number of shops sell animals. “We found out which stalls in the Wuhan seafood market had the virus,” Tan Wenjie, a researcher with the Institute for Viral Disease Prevention and Control at the Chinese Center for Disease Control and Prevention, told media. of state China Daily at the time. . “This is an important finding and we will investigate which animal was the source.”
But the samples had never been shared before appearing in GISAID earlier this month. After Goldstein and his team contacted Gao, the series again disappeared from the GISAID website.
“We were surprised to see it removed,” Goldstein said. “Questions about timing are questions the CDC can answer.”
GISAID said in a statement that the records are currently being updated with newer additional data as part of revisions to the manuscript submitted for publication. Although existing records may be temporarily invisible while they’re being updated, the organization won’t delete the records, he said.
The statement said the WHO encourages researchers to use the data to collaborate with their Chinese counterparts.
“The story isn’t over yet,” said Gerald Parker, director of the pandemic and biosecurity policy program at Texas A&M University’s Bush School of Government and Human Service. “We still need an objective and transparent investigation, with a forensic force, that brings together the intelligence and scientific communities.”