On Sept. 16, President Obama visited the headquarters of the Centers for Disease Control and Prevention in Atlanta. The agency is the lead organization in the federal government’s efforts to prevent the introduction and spread of the Ebola virus into the United States, and Obama used his remarks there to update Americans on those efforts.

The chances of an Ebola outbreak in the United States are “extremely low,” Obama said. U.S. are working with officials in Africa “to increase screening at airports so that someone with the virus doesn’t get on a plane for the United States.” And then this: