Ebowla patient Dr. Craig Spencer recently returned to the U.S. from the front lines of the Ebola crisis in West Africa. Upon his return, Dr. Spencer was subjected to “enhanced screening” at the airport, according to the CDC.

Tweeters drew the obvious conclusion:

Well, the conclusion is obvious to everyone except the CDC, apparently.

That was such a profound point that the CDC decided to tweet it again:

No kidding? Funny how that happens when a virus has an incubation period that lasts several weeks (at least).

So what exactly is the point of enhanced screening, again?