The cyclosporiasis outbreak, the nation's largest, is currently affecting nine states.

It's probably not news to you that a parasite that causes explosive diarrhea has been surging in the US.

Some US states are facing a large and growing outbreak of diarrhea caused by cyclospora, a microscopic parasite that can contaminate fresh food or water.

More than 12,000 cases of cyclosporiasis have been reported across 40 states

Investigators believe additional states will help them better construct how cyclosporiasis moved through the nation's food supply.