Thank you for the detailed response. As a layperson, these specifics are over my head.
Assuming everything you say is true, that still would not rule out a lab leak of a virus collected from nature, would it?
>You can't do it in the time we've been able to handle viruses like this or modify them in the ways we can. You'd have needed to start a few decades ago, have tools that we've only just invented, and a huge number of willing test subjects.
Does this imply that covid19 has been circulating among humans for a very long time?
Yes, a lab leak of a virus collected from nature is the most plausible of these lab theories.
But the epidemiological evidence points to covid-19 originating outside wuhan entirely, that's why I find that theory less likely, among other reasons. See here:
Also if they had collected it in nature, it would have been in their freezers, or likely that people involved in that research would have been patient zero etc. See here:
Wuhan institute of virology also aren't the labs I'm worried about. They were built and designed by very reputable people in the virology community. Not saying you should trust them, but at least recognize that the people who are most qualified to distrust them think it's unlikely.
>Does this imply covid-19 has been circulating in humans a long time?
No, it implies it was relatively stable passing amongst several species of bats (and other related mammals) before a single or a few crossover events into humans recently.
It's behaving exactly like we would expect a zoonotic transmission to behave. It's not very well adapted to bats, it's not very well adapted to humans. It's sort of "promiscuous" likely because it has infected several different species over several decades before arriving in humans.
> They were built and designed by very reputable people in the virology community.
Anyone under the thumb of communist party minders is by definition not in a position to freely act as a very reputable person. They may very well have a reputation, but they are not free to fulfill it well.
Scientists in China play balancing acts all the time. They have to assess the risks and decide on a case by case basis what to say. I’m not inside her head but perhaps she also wants to try to maintain some scientific credibility for herself. It’s fine to wonder why, as you are, as long as you don’t assume that the question existing acts as a validation of your position.
I live in a rural place in the middle of the USA, but we have a large number of international travelers pass through. I am aware of several local cases that seem very COVID-like that predate January 2020. Two of these I knew about before anyone heard of the outbreak in Hubei. I remember discussing at the time how it was weird to hear of someone in their early 50s to be hospitalized with pneumonia from 'flu'. Anyway I wonder if you have heard any similar reports and your thoughts on the potential for much earlier transmission in the US.
It's not super likely, because we don't have the epidemiological data (increased deaths from non-influenza pneumonia at a large scale) to support that, to my knowledge.
It's certainly possible. And it is true that our methods of detection of viruses are ill-equipped so you can assume we're almost always behind the curve a bit.
But there also isn't much more than anecdote to support this. Lots of people get influenza-based pneumonia in the winter. Could you consider the possibility that your recollection is now tainted? And that you are primed to notice those events more? It was also already a very bad flu season. See here:
Another kind of issue is that early reports of "SARS-2 positive serum!" were overblown, which colored a lot of news reports on this. They basically made the tests too "promiscuous" so they also detected antibodies against common cold coronaviruses. That was a big problem. If you're curious about how tests like this work, you can check out this other post I wrote on that! Antibody tests are actually my specialty!
Assuming everything you say is true, that still would not rule out a lab leak of a virus collected from nature, would it?
>You can't do it in the time we've been able to handle viruses like this or modify them in the ways we can. You'd have needed to start a few decades ago, have tools that we've only just invented, and a huge number of willing test subjects.
Does this imply that covid19 has been circulating among humans for a very long time?