Michigan health officials are tracking a fast-moving outbreak of a diarrhea-causing intestinal parasite that has produced more than 700 confirmed cases since late June. The Michigan Department of Health and Human Services reported that as of July 6, the state had received reports of over 700 cases since June 22, along with 36 hospitalizations, according to Ars Technica.
The numbers have climbed sharply. On June 30, the health department reported 170 cases. By July 4, that number had jumped to 572. The cases are concentrated in the southeastern region of the state.
The microscopic unicellular parasite responsible is Cyclospora cayetanensis, which causes a disease called cyclosporiasis. The infection is generally not life-threatening, but the Centers for Disease Control and Prevention says it usually causes watery diarrhea with frequent and sometimes explosive bowel movements. The CDC says these intestinal symptoms usually last about a week but can go on for two or more weeks, with dehydration being one of the most significant concerns.
The parasite spreads through contaminated produce and water. It is shed in feces and can end up on fruits and vegetables. Thoroughly washing and cleaning produce before eating, along with diligent hand hygiene, are the key prevention methods health officials point to.
Investigators have not yet identified a source. Previous outbreaks nationally have been linked to bagged salad mixes and kits, cilantro, basil, raspberries, snow peas, and green onions, the Michigan health department has noted.
"At this time, no specific produce grower, supplier or type of produce has been identified as the source," an MDHHS spokesperson told Ars Technica. State officials are coordinating with local health departments in the southeastern region and interviewing cases in an effort to identify common exposures. The state has also shared its case data with the CDC.
The investigation remains active, with officials working to determine whether a single source or multiple sources are responsible for the outbreak.
