Michigan is grappling with one of the largest cyclospora outbreaks in state and national history, with nearly 1,000 confirmed cases of the parasitic infection. The Michigan Department of Health and Human Services (MDHHS) reported Wednesday that 992 residents have been diagnosed, and 40 have been hospitalized. No fatalities have been linked to the outbreak.
The surge began in late June, when the state first flagged 170 cases. Health officials are working to trace the source, which remains unidentified. The MDHHS is collaborating with local health departments and federal partners to investigate and update the public.
Cyclospora: A Parasite That Causes Severe Symptoms
The infection stems from a microscopic parasite that invades the intestines, triggering watery diarrhea that can be frequent and explosive, according to the Centers for Disease Control and Prevention (CDC). Without antibiotic treatment, symptoms can persist for weeks or months, though the illness is rarely life-threatening. Transmission occurs through consumption of food or water contaminated with feces, with an incubation period of two days to two weeks. Person-to-person spread is uncommon, and the parasite is typically linked to fresh produce.
University of Minnesota researcher Melanie Firestone told the Associated Press that cyclospora is often underreported, as standard food poisoning tests may not detect it. Before Michigan's outbreak, only 145 cases were reported nationwide between May 1 and June 16. The CDC noted that no single source connects all cases across the country, but typical season began May 1.
The CDC has tracked cyclospora since a 1997 outbreak tied to Guatemalan raspberries that sickened over 1,000 people in the U.S. and Canada. A 2019 outbreak linked to Mexican basil caused more than 2,400 cases, according to the National Institutes of Health.
Prevention Advice and Political Context
MDHHS advises residents to discard outer layers of lettuce heads, wash inner leaves, and thoroughly clean cilantro, basil, green onions, and snow peas under running water. Raspberries are particularly tricky due to their bumpy surface; cooking them in pies or jams is safest, as freezing does not eliminate the parasite.
The outbreak adds a public health dimension to Michigan's political landscape, where the Senate primary is tightening following a key candidate's exit. Meanwhile, the CDC is also probing a similar cyclospora outbreak across 18 states, raising concerns about produce safety. Health officials emphasize that cooking all suspect foods is the most reliable preventive measure.
