Centers for Disease Control

Five local cases of malaria in the U.S. have been reported --mosquitoes carrying the malaria parasite bit and infected the individuals. How worried should we be? Is climate change a factor?

U.S. health officials said equipping six cities with extra testing would pick up under-the-radar viral spread. But an NPR investigation finds conflicts and shortages caused painful delays.

COVIDView, modeled on a tool used to track seasonal flu, pulls data from an array of sources to provide a better picture of the virus' spread. But some say it still falls far short of what's needed.

It all started with a funeral in Liberia. Guests fell ill but no one knew why. Time to summon the "disease detectives."