As the world knows, we face an emerging virus threat in the Wuhan coronavirus (2019-nCoV) outbreak. The problem is, right now there are several important things that we don't know about the situation. The mortality rate, the ease of human-human transmission, the rate of mutation of the virus (and how many strains we might be dealing with all of these need more clarity. Unfortunately, we've already gone past the MERS outbreak in severity (which until now was the most recent new coronavirus to make the jump into humans). If were fortunate, though, well still have something that will be worrisome, but not as bad as (say) the usual flu numbers (many people don't realize that influenza kills tens of thousands of people in the US each year). The worst case, though, is something like 1918, and we really, really don't need that.