Cholera is a disease caused by infection of the intestine by bacteria. The infection is usually mild, but at times can be severe. Though cholera is extremely rare in the United States, anyone can get cholera if they drink water or eat food contaminated with the bacteria. In an outbreak situation, the source of contamination is usually the feces (stool) of an infected person. The disease can spread rapidly in areas with inadequate treatment of sewage and drinking water.