Overview
- In recent weeks health officials have recorded a rapid rise in cyclosporiasis cases concentrated in Michigan, with state reports ranging from hundreds to more than 1,500 cases and additional clusters reported in New York, Ohio and Texas.
- The illness is caused by the single-celled parasite Cyclospora cayetanensis and spreads when people ingest food or water contaminated with fecal matter, with past U.S. outbreaks linked to fresh produce such as raspberries, basil and salad mixes.
- Typical symptoms include watery, often severe diarrhea, stomach cramps, nausea and fatigue that usually appear about a week after exposure and can cause rapid weight loss in some patients.
- Diagnosis requires specific laboratory testing and the standard treatment is a prescribed antibiotic course that clears the parasite; public-health labs and clinicians are intensifying testing to confirm cases.
- State and federal investigators have not identified a single contaminated food source, officials warn that farm-level contamination and the parasite's need to mature in the environment make traceback hard, and they advise thoroughly washing produce and seeking prompt testing and treatment for symptomatic people.