5 ms·

Could you remind us what the "non-lab-leak scenario" is again? To be clear, is your "likeliness" determined on whether we can find a creature that is more simi

Could you remind us what the "non-lab-leak scenario" is again? To be clear, is your "likeliness" determined on whether we can find a creature that is more similar to covid than RaTG13 (we haven't) or something else?

jacquesm 3y ago
The non lab leak scenario is just what it historically has been for ~70% of all viruses that we can trace (and probably the remainder as well, but we have no evidence): zoonotic jump.
- Reason077 3y ago
  The lab-leak scenario presumes zoonotic jump, too. Just rather than from something in the wild, it's from humanized (ACE2-transgenic) mice, which WIV was known to be using to study SARS-like Coronaviruses.
  - jacquesm 3y ago
    SARS-like CoronaViruses != COVID19. All cows are animals. Not all animals are cows.
    - Reason077 3y ago
      The coronaviruses being studied at WIV included RaTG13, one of the closest relatives (96.1% genomic match) to SARS-CoV-2 ever found in the wild. But a key difference between SARS-CoV-2 and it's wild relatives is the spike protein with affinity for the ACE2 receptor, so it would have had to have evolved through an intermediate host with a human-like ACE2 receptor. For example, ACE2-transgenic lab mice. This does not itself rule out the wild-origin theory, but no wild host that could explain the missing link from RaTG13 to SARS-CoV-2 has yet been found.
      - jacquesm 3y ago
        96.1 genomic match is less than the match between a male chimpanzee and a male human.
        deleted 3y ago
        [deleted]
        MrOwnPut 3y ago
        There is no closer match to SARS-CoV-2 found in the wild. Pangolins were floated for awhile but I believe the samples were 91%~ If there was GoF being done on the sample (adding of the spike protein to infect humans), that could be the remaining percentage.
        jacquesm 3y ago
        Indeed. So the only reasonable conclusion so far is that we haven't found the reservoir host yet. This may take a while and it may even never happen. If and when we do we will finally be able to make another step in this whole saga.
        MrOwnPut 3y ago
        You ignored this part of my statement: > If there was GoF being done on the sample (adding of the spike protein to infect humans), that could be the remaining percentage. I do not believe one bit the only "reasonable conclusion" is it has to be from nature. Between the lab sample, the outbreak area, the GoF program being run, the timing, history of lab leaks, and the reaction, a lab leak is very reasonable...
        lcnPylGDnU4H9OF 3y ago
        I think there may have been a slight misunderstanding here (I'm not particularly familiar with this topic so I may have some concepts mistaken): > The lab-leak scenario presumes zoonotic jump, too. Just rather than from something in the wild, it's from humanized (ACE2-transgenic) mice > So the only reasonable conclusion so far is that we haven't found the reservoir host yet. > I do not believe one bit the only "reasonable conclusion" is it has to be from nature. If it's discovered that the reservoir host was a mouse in a lab at WIV then "we will finally be able to make another step in this whole saga" in the same way as it being discovered as a wild host. It might be worth reading their comment again. (Again, I'm not deeply familiar with this topic and may be totally off base; gluing together my personal understanding of the meanings of these words has me arriving at this conclusion. I'm also attempting to clarify someone else's statements so take another grain of salt for that.)

jacquesm 3y ago

The non lab leak scenario is just what it historically has been for ~70% of all viruses that we can trace (and probably the remainder as well, but we have no evidence): zoonotic jump.

Reason077 3y ago
The lab-leak scenario presumes zoonotic jump, too. Just rather than from something in the wild, it's from humanized (ACE2-transgenic) mice, which WIV was known to be using to study SARS-like Coronaviruses.
- jacquesm 3y ago
  SARS-like CoronaViruses != COVID19. All cows are animals. Not all animals are cows.
  - Reason077 3y ago
    The coronaviruses being studied at WIV included RaTG13, one of the closest relatives (96.1% genomic match) to SARS-CoV-2 ever found in the wild. But a key difference between SARS-CoV-2 and it's wild relatives is the spike protein with affinity for the ACE2 receptor, so it would have had to have evolved through an intermediate host with a human-like ACE2 receptor. For example, ACE2-transgenic lab mice. This does not itself rule out the wild-origin theory, but no wild host that could explain the missing link from RaTG13 to SARS-CoV-2 has yet been found.
    - jacquesm 3y ago
      96.1 genomic match is less than the match between a male chimpanzee and a male human.
      - deleted 3y ago
        [deleted]
      - MrOwnPut 3y ago
        There is no closer match to SARS-CoV-2 found in the wild. Pangolins were floated for awhile but I believe the samples were 91%~ If there was GoF being done on the sample (adding of the spike protein to infect humans), that could be the remaining percentage.
        jacquesm 3y ago
        Indeed. So the only reasonable conclusion so far is that we haven't found the reservoir host yet. This may take a while and it may even never happen. If and when we do we will finally be able to make another step in this whole saga.
        MrOwnPut 3y ago
        You ignored this part of my statement: > If there was GoF being done on the sample (adding of the spike protein to infect humans), that could be the remaining percentage. I do not believe one bit the only "reasonable conclusion" is it has to be from nature. Between the lab sample, the outbreak area, the GoF program being run, the timing, history of lab leaks, and the reaction, a lab leak is very reasonable...
        lcnPylGDnU4H9OF 3y ago
        I think there may have been a slight misunderstanding here (I'm not particularly familiar with this topic so I may have some concepts mistaken): > The lab-leak scenario presumes zoonotic jump, too. Just rather than from something in the wild, it's from humanized (ACE2-transgenic) mice > So the only reasonable conclusion so far is that we haven't found the reservoir host yet. > I do not believe one bit the only "reasonable conclusion" is it has to be from nature. If it's discovered that the reservoir host was a mouse in a lab at WIV then "we will finally be able to make another step in this whole saga" in the same way as it being discovered as a wild host. It might be worth reading their comment again. (Again, I'm not deeply familiar with this topic and may be totally off base; gluing together my personal understanding of the meanings of these words has me arriving at this conclusion. I'm also attempting to clarify someone else's statements so take another grain of salt for that.)