But the exact same thing that makes it substantial evidence (there aren’t many such labs, whereas there are many opportunities for natural zoonosis which could happen in a wider variety of places) also means that the prior is low.
Why does that mean the prior is low?
I see no reason why I would assume that the prior for a lab to leak a virus with airborne transmission when they handle it under biosafety level II which is not designed to prevent airborne transmission is low.
Why does that mean the prior is low?
I see no reason why I would assume that the prior for a lab to leak a virus with airborne transmission when they handle it under biosafety level II which is not designed to prevent airborne transmission is low.
The prior for any given newly-emerged virus being a natural zoonosis rather than a lab leak is higher when there are fewer labs to leak.
I agree that the prior for a leak happening from any given lab at any given time doesn’t depend on how many labs there are, of course.