KLAIN: “But the fact is we knew a lot more about Ebola in the fall of 2014 than we know about this virus right now. Leading medical experts didn't know it existed six weeks ago. So, there's just a lot of uncertainty about the basics, uncertainty about how infectious it truly is, how much it's going to spread, how much it's spread already in China, how much should we expect it to spread outside of China, doubts about how lethal it is, what will the fatality rate, the rate of serious illnesses wind up being. So what I'd say is I think we have a reason to be concerned, there's a reason for the U.S. to be more aggressive in response than what's been mounted so far in many respects, a reason to be prepared for something. But I think no reason yet to be fearful, no reason yet to really panic or anything like that. I just think there's a lot of unknowns about this virus and what its path is going to be."