3 ms·

I guess different people have different definition for "significant circumstantial evidence". We have two hypotheses: 1. virus come from seafood market, 2. viru

by nacc 6y ago

I guess different people have different definition for "significant circumstantial evidence". We have two hypotheses: 1. virus come from seafood market, 2. virus come from lab. Let's see the likelihood for each with each piece of data. Data 1: Index case. There is no evidence that the "index case" is ever found. The earliest patient backtracked to Nov 2019 [1], but there is no report that patient is related to the lab / market. Data 2: close lab location to seafood market. This alone does not favor one hypothesis to other, since distance is communicative. The virus can start from either location to the other. Data 3: Bat species. Not sure what aspect of the bat species is related, but one thing to note is the virus sample found in bat is only 96% similar to the virus sample. At 30k genome and an mutation rate of 1bp per two weeks, these samples have at least 20 years worth of evolution time. Unlikely to relate to either lab / seafood market. Some researchers believe there might be intermediate hosts, but there doesn't seem to be evidence what that intermediate host might be. Data 4. Earlier lab accident. I think the lab accident data is actually not favoring the lab hypothesis. If you think in a Bayesian way, earlier lab leaks are quickly identified and controlled. Given that this time it is not, your belief for lab leak should decrease a bit. Anyway, for the lab data what's important is the likelihood of (the lab, without genetic engineering, get a hold of this virus, and leaked) vs. (an intermediate host). Having worked in Biohazard level 2/3 labs, I think a leak from level 4 lab will be more unlikely compared to intermediate host, but we don't have any good estimate of the two likelihood yet. So I think people can have strong beliefs about where the virus come from (since everyone's prior is different), but from the data the likelihood really doesn't strongly favor any of the two hypotheses. [1] https://www.scmp.com/news/china/society/article/3074991/coronavirus-chinas-first-confirmed-covid-19-case-traced-back https://www.scmp.com/news/china/society/article/3074991/coro...

jnbiche 6y ago
> but from the data the likelihood really doesn't strongly favor any of the two hypotheses. I mostly agree with this. I personally think the totality of the evidence favors the lab hypothesis, for a variety of reasons (note the the other lab conducting and publishing about live bat research in Wuhan - the Wuhan Centers for Disease Control - was BL2, I agree it's unlikely to be the BL4 Institute of Virology). But I also agree there's also a decent probability it was the market. I'd say 3:1, if I had to put a number to it. However, folks on the other side seem to want to categorically rule out an accidental lab release, seemingly for some social or political reason. That seems very wrong-headed. Edit: btw, regarding your point 4, a Bayesian approach would seem to provide more support for the accidental lab release, given the posterior. That's actually the approach I'm using here, I even meant to mention it in one of my comments. That said, I hadn't thought of your interpretation. I'll think about that, but I think that what may be different here is that one of the labs in question here isn't under national control, unlike the previous ones that have had accidental releases. And we all know the problems provincial governments have had with corruption and coverup. But I'll think about what you said.
paganel 6y ago
The main data that for a person like me "strongly favors" the lab hypothesis is the fact that the Chinese authorities are not letting in any international and independent commission to investigate what happened in said lab (which they should have allowed happening since at least January). I've commented before on this website and got downvoted (that was 3-4 weeks, though, when the public/political discourse wasn't yet focused on this) if it looks like bio-terror attack and it quacks like a bio-terror attack it might as well be a bio-terror attack, after all, the US has gone to war for some photos of metal tubes in the Iraqi desert that hadn't caused a global pandemic and the world economy to nose-dive (with the happy exception of the country from which it all started).
gbax 6y ago
> Given that this time it is not, your belief for lab leak should decrease a bit. China's ambitions and role in the World are very different in 2020 than they were in 2004. If China manages to contain this pandemic better than the US and Europe, it'll come out relatively stronger. We do not have hard evidence about the lab leak hypothesis and we must have it before drawing any conclusions. The timing of the economic repercussions on the US/EU seems to come at a strategically perfect time for China to gain politically. This would be a much better alternative to a way and much easier to cover up. All relevant evidence may have been wiped away, for all we know. All I am saying is that there are definitely reasons to have different Bayesian priors in 2020 compared to 2004. Evidence is still weak, I agree.

by nacc 6y ago

jnbiche 6y ago

> but from the data the likelihood really doesn't strongly favor any of the two hypotheses. I mostly agree with this. I personally think the totality of the evidence favors the lab hypothesis, for a variety of reasons (note the the other lab conducting and publishing about live bat research in Wuhan - the Wuhan Centers for Disease Control - was BL2, I agree it's unlikely to be the BL4 Institute of Virology). But I also agree there's also a decent probability it was the market. I'd say 3:1, if I had to put a number to it. However, folks on the other side seem to want to categorically rule out an accidental lab release, seemingly for some social or political reason. That seems very wrong-headed. Edit: btw, regarding your point 4, a Bayesian approach would seem to provide more support for the accidental lab release, given the posterior. That's actually the approach I'm using here, I even meant to mention it in one of my comments. That said, I hadn't thought of your interpretation. I'll think about that, but I think that what may be different here is that one of the labs in question here isn't under national control, unlike the previous ones that have had accidental releases. And we all know the problems provincial governments have had with corruption and coverup. But I'll think about what you said.

paganel 6y ago

The main data that for a person like me "strongly favors" the lab hypothesis is the fact that the Chinese authorities are not letting in any international and independent commission to investigate what happened in said lab (which they should have allowed happening since at least January). I've commented before on this website and got downvoted (that was 3-4 weeks, though, when the public/political discourse wasn't yet focused on this) if it looks like bio-terror attack and it quacks like a bio-terror attack it might as well be a bio-terror attack, after all, the US has gone to war for some photos of metal tubes in the Iraqi desert that hadn't caused a global pandemic and the world economy to nose-dive (with the happy exception of the country from which it all started).

gbax 6y ago

> Given that this time it is not, your belief for lab leak should decrease a bit. China's ambitions and role in the World are very different in 2020 than they were in 2004. If China manages to contain this pandemic better than the US and Europe, it'll come out relatively stronger. We do not have hard evidence about the lab leak hypothesis and we must have it before drawing any conclusions. The timing of the economic repercussions on the US/EU seems to come at a strategically perfect time for China to gain politically. This would be a much better alternative to a way and much easier to cover up. All relevant evidence may have been wiped away, for all we know. All I am saying is that there are definitely reasons to have different Bayesian priors in 2020 compared to 2004. Evidence is still weak, I agree.