The Brief The NYC Health Department says it is investigating 447 cyclosporiasis cases since May 1. Cases have been reported in at least 31 states, according to the U.S. Centers for Disease Control and Prevention. New York City's health department said Thursday it's investigating 447 new cases of cyclosporiasis, the foodborne parasitic infection known to cause "explosive diarrhea," since May 1. Cyclosporiasis can also be prevented by avoiding water or food that may be contaminated with stool, according to the health department. Federal health officials said they were also tracking outbreaks of cyclosporiasis nationally that are unrelated.