Michigan has become the epicenter of a significant cyclosporiasis outbreak, with state health officials reporting over 10,700 cases. This surge contributes to a nationwide total of approximately 18,000 detected cases of the parasitic illness, which is typically contracted through contaminated food or water.
Nationwide, 193 individuals in Michigan have been hospitalized due to cyclosporiasis. The Centers for Disease Control and Prevention (CDC) notes that official figures often trail behind local data. Other states reporting substantial case numbers include Ohio, with 4,000 infections, followed by Illinois, Indiana, North Carolina, and New York, each with up to 500 cases. In total, 45 states have recorded at least one case this year.
The U.S. Food and Drug Administration (FDA) is tracking six distinct outbreaks of Cyclospora, though these are not necessarily interconnected. One major outbreak, linked to shredded iceberg lettuce from Taylor Farms, has been associated with cases in nine states: Illinois, Indiana, Kansas, Kentucky, Michigan, Ohio, Oklahoma, Pennsylvania, and West Virginia. Taylor Farms has since recalled the affected lettuce and temporarily shut down a processing facility in Mexico identified as a potential source.
However, the FDA later indicated that lettuce from Taylor Farms yielded a false-positive result for the parasite, complicating the investigation. This facility supplies five-pound bags of shredded iceberg lettuce to major distributors like Taco Bell and Sysco.
In Michigan, where cases have been rising since late June, health officials have not yet identified a definitive source. They are advising residents to thoroughly wash and trim certain produce, including lettuce, leafy greens, cilantro, basil, green onions, raspberries, and snow peas, before consumption. The majority of infections in Michigan are occurring in individuals in their 20s, 30s, and 40s, with Oakland County, a part of metropolitan Detroit, reporting the highest number of cases in the state, exceeding 1,000.
Cyclosporiasis symptoms typically include explosive diarrhea, abdominal cramping, nausea, vomiting, and fatigue. Unlike some other gastrointestinal illnesses, these symptoms can be persistent or recurrent rather than resolving within a few days. Without treatment, the infection can last for weeks.
Experts recommend that individuals experiencing diarrhea lasting more than a few days should seek medical attention and specifically request a test for Cyclospora, as it is not a standard diagnostic test. The infection is treatable with the antibiotic trimethoprim-sulfamethoxazole.
The parasite, Cyclospora cayetanensis, takes approximately one to two weeks to mature after being excreted. While consumption of contaminated produce is the most common route of infection, experts note that theoretical transmission through contaminated surfaces is also possible. Michigan typically records around 50 cases of this parasite annually, making the current surge exceptionally high.
