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The nearest relatives to SARS-CoV-2 are found in Yunnan and Laos. The only known link to Wuhan is the Wuhan Institute of Virology sampled both areas. They refu
by Biorealism 3y ago
The nearest relatives to SARS-CoV-2 are found in Yunnan and Laos. The only known link to Wuhan is the Wuhan Institute of Virology sampled both areas.
They refuse to share their records with WHO or the NIH. That's a crucial caveat when saying there is no evidence they held a precursor. We don't know as they have refused to share their database.
The Times article is interesting as it suggests the work in DEFUSE to add furin cleavage sites went ahead and they passaged the virus in humanized mice. This would explain the furin site not seen in other sarbecoviruses and why humans topped the list for binding affinity from the outset.
Note the cases near the market are based on what David Relman described as "hopelessly impoverished" early case data. There was also sampling bias in retrospectively counting cases as market link was often required. WHO hasn't accepted market origin in part as there were likely much earlier cases than those in December linked to the market where no animals tested positive.
- inciampati 3y ago> why humans topped the list for binding affinity from the outset This is an unbelievable coincidence that makes the zoonotic spillover hypothesis laughable. To a biologist, the likelihood of this happening by chance is clear: virtually 0. But explaining the size of the space of optimal solutions to a given binding problem versus the space of good solutions to the general public, well, that's really hard too. So an obvious and completely non-circumstantial piece of evidence is the last one in the public's mind. And we are still acting like there is a question of where the virus came from, and we will be for decades, or at least until the average level of biology education is raised by a few sharp degrees.
- randomperson01 3y ago[dead]
- sudosysgen 3y agoThat's untrue. Viruses which spillover may spread across humans at a low level of efficiency for months, mutating for higher affinity towards humans, and only becoming pandemic once a high level of affinity has been achieved. All viruses which have higher affinity for humans spilled over, didn't they?
- raccoondogs 3y agoThat's what happened with H1N1 but we know that hasn't happened with Sars2 because Sars2 only spreads efficiently with a furin cleavage site but the furin cleavage site also makes it more pathogenic so it would definitely not spread undetected.
- sudosysgen 3y agoStudies have found that people living near bats in Yunnan have immunity against this class of coronaviruses due to exposure, which would strongly blunt pathogenicity. There is also more to pathogenicity than you let on.