Shigellosis is an illness, caused by infection by bacteria of the genus Shigella. It accounts for less than 10% of the reported outbreaks of foodborne illness in the USA. Shigella rarely occurs in animals; principally a disease of humans except other primates such as monkeys and chimpanzees. The organism is frequently found in water polluted with human feces, and is transmitted via the fecal-oral route.