Diarrhea Outbreak: Cyclospora Sickens Thousands Nationwide

As of July 2026, a significant outbreak of cyclosporiasis has affected nearly 3,000 individuals across 31 U.S. states, resulting in 86 hospitalizations. This foodborne illness, caused by the cyclospora parasite, is characterized by severe, watery diarrhea. Health officials are diligently working to pinpoint the outbreak's source, with initial investigations suggesting a link to fresh produce, which historically harbors the parasite on fruits, vegetables, and herbs.

Michigan has reported the highest number of cases, with over 1,500 infections and numerous hospitalizations, prompting state laboratories to sequence the parasite's genome for potential source identification. While the CDC confirms 843 U.S.-acquired cases, over 1,500 more are under investigation. The current numbers represent a substantial increase compared to the same period in the previous year.

Symptoms typically appear about a week after consumption and can include fatigue and body aches, but are most distinctively marked by explosive, watery diarrhea. Treatment usually involves antibiotics, with about 10% of patients requiring hospitalization due to dehydration. Health authorities advise thorough washing of produce and cooking food as the surest methods to kill the parasite, while acknowledging the difficulty in tracing contaminated food items consumed weeks prior.