“From their perspective it would be akin to closing the barn door after the horses are out, because we already have cases here in the United States.”

I’m no epidemiologist, Mark, but isn’t that statement preposterous — unless, I suppose, we know for a fact that every conceivable infected Mexican is already in the United States?

I mean, if the possibility (probability, certainty . . .) of additional infected people coming into the country is of no concern, why on earth are we trying to identify, locate, and quarantine the infected people (Americans and others) who are here? Why did President Obama yesterday suggest that schools should close if they have infected students, teachers, or staff? I guess I was under the crazy misconception that it was because exposure to infected people risked additional infections, which would themselves then spread the flu, causing a geometric increase in the infected population — you know, like an epidemic. What am I missing?