Thread by @kakape

My colleague @jcohen and I spent the last days talking to a lot of researchers to understand where the #2019nCoV epidemic is heading: What are realistic scenarios and what data do we need to understand what scenario we are heading for? sciencemag.org/news/2020/02/b…

@jcohen Best-case scenario at this point is containing the #2019nCoV outbreak in China. That is what @WHO is going for. Tedros has said several times that his strategy is to fight the disease there at the center, while trying to keep it from gaining a foothold elsewhere.

@jcohen @WHO Is that still realistic? Some people, like @MarionKoopmans think it’s still possible. She points out that as far as we know no exported cases have led to sustained transmission. If that pattern holds, she says, “there still is the possibility it will bend off.”

@jcohen @WHO @MarionKoopmans It depends to a large part on how much transmission there is from people with little or no symptoms. If it’s a lot, it will be very hard to stop the virus spreading. If there is little, “isolation and social distancing can have a big impact”, says @alexvespi.

@jcohen @WHO @MarionKoopmans @alexvespi This is why it is so crucial have good data from #2019nCoV clusters like the German one (and why the flaws in the NEJM publication were so important). There is increasing evidence, however, for spread from people with very mild disease (see my thread from yesterday).

@jcohen @WHO @MarionKoopmans @alexvespi Most researchers we talked to then, are pessimistic about the containment scenario then. As @mlipsitch says: "I would be really shocked if in 2 or 3 weeks there wasn’t ongoing transmission with hundreds of cases in several countries on several continents.” So that’s scenario 2:

@jcohen @WHO @MarionKoopmans @alexvespi @mlipsitch A pandemic. In this case questions about how high the case fatality rate is will loom large. A deadlier pathogen does not just mean more deaths, it means more strain on the health care system, more fear and panic, possibly more severe countermeasures.

@jcohen @WHO @MarionKoopmans @alexvespi @mlipsitch To get a better handle on this, scientists again need better estimates of how many mild cases there are that may have been missed. So it all goes back to finding the denominator. Scientists are working on that, but as @alexvespi says: “this beast is moving very fast"

@jcohen @WHO @MarionKoopmans @alexvespi @mlipsitch Let me end on a hopeful note: One big question is what influence the climate may play. Influenza virus is seasonal and some have argued that warm weather helped quash SARS. If sth like that is true for #2019nCoV, it could still help us make scenario 1 - containment - a reality.