US Cyclospora Outbreak Sickens Thousands Across 31 States

The U.S. Centers for Disease Control and Prevention (CDC) has confirmed 843 cases of cyclosporiasis – an intestinal infection caused by the parasite Cyclospora cayetanensis – in 31 states since early May, with more than 1,500 suspected cases under investigation. Eighty‑six patients have been hospitalized, but no deaths have been reported.

Michigan bears the brunt of the outbreak, reporting over 1,000 diagnoses, while New York, Ohio and Illinois have also recorded several hundred cases. Smaller clusters have been identified in Florida (about 50 cases), New Hampshire (2 cases) and other states. The parasite spreads through ingestion of fresh produce or water contaminated with fecal matter; person‑to‑person transmission is considered unlikely. Authorities have not yet pinpointed a single food source, and some experts suggest contaminated irrigation water or recent flooding may play a role.

Health officials advise rigorous hygiene: wash all fruits and vegetables under running water, scrub firm produce, remove damaged portions, and consider cooking leafy greens and herbs, as typical kitchen disinfectants do not reliably kill the parasite. People experiencing explosive watery diarrhea, abdominal cramps, nausea, weight loss or fatigue are urged to seek medical care and request stool testing for Cyclospora. The recommended treatment is a course of trimethoprim‑sulfamethoxazole (Bactrim or Septra).