Origin of SARS-Cov-2 virus

Worobey dismissed.The letter was irresponsible because it dismissed evidence that was already available, and undermined the credibility of the WHO report.f
  • #1


Staff Emeritus
Science Advisor

Striking new evidence points to seafood market in Wuhan as pandemic origin point​

Neither of the papers provides the smoking gun — that is, an animal infected with the SARS-CoV-2 Coronavirus at a market.

But they come close. They provide photographic evidence of wild animals, which can be infected with and shed SARS-CoV-2, sitting in the market in late 2019 — such as raccoon dogs and a red fox. What's more, the caged animals are shown in or near a stall where scientists found SARS-CoV-2 virus on a number of surfaces, including on cages, carts and machines that process animals after they are slaughtered at the market.
Two claims in the article:
Live animals that are susceptible to COVID-19 were in the market in December 2019
Live susceptible animals were held in a stall where SARS-CoV-2 was later detected on a machine that processed animals in the market
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  • #2
I'm not fond of the idea that the competing hypothesis is that it started in a lab. We already had evidence that was extremely unlikely. To me the new studies are better read trying to figure out whether the Huanan market was the origin or not.

Unfortunately, one of the lead authors (Worobey) was a co-author of an illogical and irresponsible letter published in Science dismissing previous evidence against a lab leak. He still seems to support that letter, and here claims to have found evidence supporting a changed point of view. I'm not convinced he is being logical (just dislike Worobey's logic, I think the other authors are fine), as the previous evidence against a lab leak was stronger and more direct, while the new evidence is more circumstantial.
  • #3
Unfortunately, one of the lead authors (Worobey) was a co-author of an illogical and irresponsible letter published in Science dismissing previous evidence against a lab leak.

This statement seems to contradict what is stated in the NPR article:
Evolutionary biologist Michael Worobey helped lead two of the studies and has been at the forefront of the search for the origins of the pandemic. He has spent his career tracking down the origins of pandemics, including the origin of HIV and the 1918 flu.

Back in May, Worobey signed a letter calling for an investigation into the lab-leak theory. But then, through his own investigation, he quickly found data supporting an animal origin.
(source: NPR article cited above)

Here's a link to the May 2021 letter published in Science (of which Worobey is an author), which states that "Theories of accidental release from a lab and zoonotic spillover both remain viable" and "We must take hypotheses about both natural and laboratory spillovers seriously until we have sufficient data."
  • #4
Also, for reference, here is a link to the Worobey et al. pre-print manuscript discussed by the NPR article cited in the OP:

The Huanan market was the epicenter of SARS-CoV-2 emergence

Despite strong epidemiological links and the documented presence of SARS-CoV-2 susceptible animals, the role of the Huanan Seafood Wholesale Market in the COVID-19 pandemic remains controversial. Using spatial analyses we show that the earliest known COVID-19 cases diagnosed in December 2019 were geographically distributed near to, and centered on, this market. This distribution cannot be explained by high densities of elderly people at greater risk of symptomatic COVID-19. This pattern was stronger in cases without, rather than with, identified epidemiological links to the Huanan market, consistent with SARS-CoV-2 community transmission starting in the surrounding area. By combining spatial and genomic data, we show that both the two early lineages of SARS-CoV-2 have a clear association with the Huanan market. We also report that live mammals, including raccoon dogs, were sold at the market in late 2019 and geospatial analyses within the market show that SARS-CoV-2-positive environmental samples were strongly associated with vendors selling live animals. Together, these analyses provide dispositive evidence for the emergence of SARS-CoV-2 via the live wildlife trade and identify the Huanan market as the unambiguous epicenter of the COVID-19 pandemic.

Here's another helpful summary of the pre-print: https://www.science.org/content/blog-post/origins-pandemic
  • #5
This statement seems to contradict what is stated in the NPR article:
The Science letter that Worobey signed was illogical and irresponsible.

It was illogical, because it criticized the WHO report as concluding a lab leak was unlikely based on insufficient evidence. However, the WHO report based its conclusion on evidence: Andersen et al had shown the virus was not purposefully manipulated, Shi Zhengli who heads the relevant Wuhan laboratory had done tests to exclude the possibility they had the virus (screens of all bat samples, full catalogue of their live viruses) or that staff had been infected (antibody tests); the WHO report annex contained some additional details such as the blood samples having been drawn in March 2020, and their reply on some details as to whether all staff were tested. We also know that the laboratory was the focus of conspiracy theories, all of which are absurd and cross-checks confirm what we have thought all along: their research is to collect samples and publish descriptions of those samples. Many things that might be imagined to be secrets if some of the conspiracy theories were true were in fact openly published or mentioned by the Wuhan Institute themselves. For example, a recent paper, submitted before the pandemic, gives information about 630 novel Coronavirus sequences; it is not reasonable to imagine that including SARS2 they would have had more sequences, but chose to omit those from the paper because they knew that SARS2 would cause the pandemic. Another example is RaTG13, their closest virus to SARS2, that although was published in full only after the pandemic started, had been published in part several years before as sample ID 4991; if they were keeping SARS2 a secret, it doesn't make sense that they knew to keep SARS2 a secret, but not sample ID 4991.

The WHO report concluded a lab leak was unlikely enough not to warrant further investigation at that time, but also said that investigation might be warranted if new evidence turned up. The WHO report correctly prioritized subsequent studies such as sampling of bats and other animals to try to uncover hosts of the virus, and investigation of patient samples to try to uncover cases earlier than the current official earliest cases - note that such cases (similar to the new preprints from Worobey and colleagues) could help indicate whether eg. Huanan market was the origin, or even point back towards the WIV if such cases were found to cluster around it.

The letter was irresponsible because it was written with Alina Chan, a conspiracy theorist, and given the above evidence would only make sense if Shi Zhengli was essentially being accused - with no supporting evidence - of fabricating data. This hindered the international cooperation that would have aided the subsequent studies recommended by the WHO.

On Worobey's latest preprint, his co-authors include Marion Koopmans (an author of the WHO report whose comments suggest she continues to stand by it) and Kristian Andersen, who criticized Worobey's Science letter as "grandstanding". So I'm pretty sure that at least some of Worobey's co-authors would agree with me that his Science letter was illogical and irresponsible.
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  • #6
"Under the natural origin theory, the novel coronavirus, or SARS-CoV-2, would have originated in an animal and traveled to humans either directly or through an intermediate host animal.

This natural spillover has precedent. For example, researchers traced the first Severe Acute Respiratory Syndrome (SARS) outbreak in 2003 back to bat caves in China’s Yunnan province, and the likely intermediary host animals were masked palm civets that tested positive for the virus.

The trouble with drawing the same conclusion for COVID-19 is that no one has identified an animal that has tested positive for the novel Coronavirus that caused the global pandemic.

It's not for a lack of trying. Investigators tested more than 80,000 animals in China, including hundreds linked to the Huanan seafood market associated with the early cases of COVID-19, but "no positive result was identified for SARS-CoV-2," the World Health Organization (WHO) study on the origins of COVID-19 says."

If you insist on zoonotic transfer The Questing Beast becomes what might the characteristics of the host be and then find it. Eliminating 80,000 species would seem to certainly reduce the search parameters.

I have stated the characteristics before.

The host would be a

1. mammal
2. reside in China
3. on occasion come in contact with humans
4. be infected with a virus very similar to the SARS-CoV-2 virus

5. really knows how to hide well

Also great credence is given to reports made by Shi Zhengli.

Things to consider

1. She is omitting information
2. Additional research was conducted in other parts of the Wuhan lab that Shi Zhengli did not know about.
3. Additional research was conducted at a lab other than Wuhan.
  • #7
Thread closed temporarily for Moderation...
  • #8
As evidenced by some of the replies, we do not have enough solid evidence to say for sure where and how SARS-CoV-2 originated. We need to close this thread for now. Thanks for your participation.

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