The current epidemic of Zika virus infection in the Western Hemisphere is actually just the latest in a decade-long wave of worldwide disease outbreaks.
Today, Ron Klain officially starts his job as the country's first Ebola Czar. He may not be a scientist himself, but science should guide his policies.
Ebola has reached the US, but it's not going to spread. Several other dangerous tropical diseases, however, are already affecting millions of Americans.