For a contrarian take on the worldwide response to COVID19 by a very smart scientist, John Ioannidis @Stanford, who argues we may be (and perhaps are) over-reacting, see: statnews.com/2020/03/17/a-f… via @jflier 1/
He rightly points out that we are making huge decisions with crappy data, and he is right that we should (immediately) put into place surveillance for COVID19. Many smart scientists are working full time to assemble such data and fill in holes in data we have. 2/
Given all the data uncertainties, reasonable estimates for the case fatality ratio (CFR) of COVID19 in the general U.S. population could be between 0.05% (half as deadly as the flu) to 1% (ten times as deadly as the flu), according to Ioannidis! That's a huge range. 3/
Ioannidis fears that, when it comes to the severe measures countries around the world are taking, "It’s like an elephant being attacked by a house cat. Frustrated and trying to avoid the cat, the elephant accidentally jumps off a cliff and dies." 4/
I do not think his sense that many other scientists are being too pessimistic about the COVID19 pandemic is right, though he is quite right that, at this early stage, much is unknown about SARS-CoV-2 epidemiology. 5/
I do not think the CFR will be lower than 0.3% at the very lowest end, and I think many millions will be infected. Hence, there will be many deaths over the next year or two. Many of these deaths, alas, will occur in coming two months. 6/
For example, for a very sophisticated estimate of the CFR, based on all data and using a good method, see this discussion (and link to paper) by @StatModeling (CFR is ~1.5% in this estimate!): statmodeling.stat.columbia.edu/2020/03/07/cor… 7/ 
But most important, what I think Ioannidis ignores is the fact that we are facing an *epidemic* with a *pulse* of cases approaching us, all at once, in a wave. It's a novel pathogen (almost surely), and many get sick & die at once. Just look at what happened in Wuhan & Italy. 8/
More analysis of the Ioannidis piece, by @mlipsitch, realistically emphasizing the stark choice we are facing (the economy or many lives); I wholly agree with Lipsitch. statnews.com/2020/03/18/we-… 9/
