This is my take on the current situation.
Mass hysteria - happens all the time. A person is smart, people are dumb. Doesn't take much to create a panic. Just look at the bread shelves before a snow storm or the water aisle before a hurricane.
Media hysteria - Again happens all the time. Nothing better sells better than gloom, doom, and despair...except for maybe blood and guts.
The government response - This one is baffling me honestly. Aside from a little political posturing in an election year, a full blown government reaction is coming with pretty well bi-partisan support. The government is taking action that they know good and well will cause deep socio-economic harm, but what they know of the threat of this virus is taking precedent. I can only assume they are hearing or seeing things from China, Italy, the CDC, and god knows who else, that we the general public and universal skeptics aren't seeing.
I consider myself a universal skeptic. The media hype and public panic I could easily dismiss. The governmental reaction, at least has me puzzled, if not concerned. If you would have told me two weeks ago that this is where we would be today, I wouldn't have believed it. Makes me wonder what is coming in the next days/weeks/months.