Scientists have found new genetic evidence from a market in Wuhan, China, where COVID cases first peaked in late 2019. This finding supports the animal origin of SARS-CoV-2, the virus that causes COVID. They were presented to an advisory group convened by the World Health Organization earlier this week.
Florence Debarre, an evolutionary biologist at the French National Center for Scientific Research, said the Chinese researchers, led by George Gao, former director of the Chinese Center for Disease Control and Prevention, are working with GISAID. The sequences were then removed, but not before other researchers in various countries downloaded and analyzed them. also contained genetic material from raccoon dogs (a type of canid similar to foxes that are believed to be on the market) and other animals. The genetic material came from the same market area where SARS-CoV-2 was discovered, suggesting that raccoon dogs may have been infected with the virus (presumably by other animals) and were the first to spread the virus to humans. It suggests that there is a possibility that
The virus caused a global pandemic that killed nearly 7 million people. Debate rages on whether it was due to a natural spillover from wildlife to humans, or a laboratory leak from Wuhan’s coronavirus research facility. While the new evidence does not directly prove that SARS-CoV-2 jumped from infected raccoon dogs to humans, it does support growing evidence in favor of spillovers from animals.
“These data do not provide a definitive answer to the question of how the pandemic started, but they are all important in getting us closer to that answer,” said the World Health Organization. Director-General Tedros Adhanom Ghebreyesus said at a news briefing on Friday. The scientists analyzing the data are currently preparing a report on their findings, which they hope to publish in the near future.
Scientific American We spoke with one of the researchers who analyzed the samples, Joel Wertheim, an evolutionary biologist at the University of California, San Diego. He described the new findings and what they add to our understanding of his COVID origins.
[An edited transcript of the interview follows.]
What do the new findings tell us and how do they fit into the broader context of investigating the origins of COVID?
First of all, I’ve been waiting over a year, maybe over two years, to see these sequences. And we have long assumed that the presence of susceptible hosts and viruses would be confirmed in the same marketplace at the same time.
Did you know these samples existed but weren’t published?
yeah, that’s right [the Chinese researchers have] Run multiple sequence runs on the sample.So I don’t know when these were produced….we think the Chinese [scientists] I had an old sample, based on [a] Preprint from 2022. And we knew these samples existed because of the documents leaked in early 2020. [Editor’s note: This preprint is currently under review for possible publication.]
But that early preprint didn’t mention animal sequences, right?
Yeah, you didn’t specifically mention where the non-viral genetic material came from, except for the human-derived samples. I doubted. And, lo and behold, it is.
How strong is the current evidence for natural spillover as the origin of SARS-CoV-2?
First, I would like to say that even before these data were published, the preponderance of scientific evidence indicated a natural zoonotic spread. [an animal disease jumping into humans] for quite some time. These new data are perfectly consistent with that scenario. The point here is that I think it would be a mischaracterization to say that these sequences indicate that raccoon dogs or other mammalian host species were infected with these viruses. It’s different from a raccoon swab. And it’s not the same as watching a raccoon dog transmit a virus to a human. I don’t get that level of evidence. But first and foremost, this is forensic evidence that these putative host animals existed on the market. And they were in the same place as the virus.
Now, apparently, some of these environmental samples contain the virus because of infected humans. , it is inconceivable to say that this was just humans infecting animals. Come to think of it, this is true. No, I won’t do anything. But I think this should help convince more rational scientists.
Can you explain Laboleek’s hypothesis, at least whether there is evidence for an “honest” version of such leaks as some sort of accident?
The problem with the honest version of the Labourique hypothesis is that there is no single hypothesis. A scientist infected in the field, a scientist infected with an unexplained virus in the laboratory, serial passage or gain-of-function weaponization – that is, all of these laboratory – leak hypotheses are incompatible with each other.
Looking at the viral genome, I see nothing suspicious. [some] A type of laboratory operation. we really don’t. The most philanthropic explanation still left here is that there was a lab worker infected with a virus that the lab had yet to characterize and brought it to the Huanan market, potentially depositing it there multiple times. . They are sold there and infected.And none of these lab workers get infected [the virus] Anyone who would help an epidemiologist track it down to them [having antibodies to the virus indicative of previous infection] when testing later.
You say that a chain of events is unlikely. What are your thoughts on the Department of Energy’s recent report concluding that it was “unreliable” but that a lab leak was the most likely?
I don’t know what the Department of Energy report said. I can’t comment in detail on reports that aren’t explained or that I haven’t seen. But I can’t imagine the real evidence they have. Especially now [the new animal evidence].
These early cases [were] Link to the market. Yeah there was a lot of confusion. But after removing all the assumptions and data that didn’t stand up to scrutiny, all that was left was the market. And everything we’ve done, from geographic analysis to genomic analysis to now forensic genetic analysis, shows a natural zoonosis in the marketplace.
Regardless of the true origin of SARS-CoV-2, should you still worry about keeping your lab safe from potential leaks of the deadly pathogen?
of course. I don’t know a virologist who doesn’t take biosecurity seriously. But that discussion should be separated from his discussion of COVID when talking about gain-of-function research and laboratory safety. Because they are two different issues. The circumstances of origin are irrelevant and it would be a mistake to confuse the two.
Coming back to the new genetic evidence, what information do you hope to gather in the coming weeks?
there is genetic material from [market] A stall that didn’t have SARS-CoV-2. I am very interested in seeing them. There is more genetic data from the market that is not yet available….I suspect the previous sequencing run may still be there. , [study them].
Will you and your colleagues make these findings public?
We plan to publish a report summarizing the results of the survey.i would say [the time frame will be] A few days, sometimes hours.
