An outbreak of cyclosporiasis, an intestinal illness caused by a microscopic parasite, has led to thousands of reported cases across multiple U.S. states in recent weeks. The primary symptom is frequent, watery, and sometimes explosive diarrhea.
Current Outbreak Details
As of mid-June, the U.S. Centers for Disease Control and Prevention (CDC) reported 145 cases of cyclosporiasis across 17 states. While no deaths have been reported, 20 individuals were hospitalized. The outbreak is particularly concentrated in Michigan, where nearly 1,000 cases were diagnosed within a two-week period ending July 8. Illinois reported 141 cases as of July 7, described as higher-than-average, and Ohio has recorded 177 cases.
Health officials note that the actual number of infections is likely higher, as not everyone with symptoms seeks medical care or gets tested. The illness typically appears about one week after infection and, if untreated, can last from a few days to over a month, with symptoms potentially recurring.
Understanding Cyclosporiasis
Cyclosporiasis is caused by the parasite Cyclospora cayetanensis. Infection occurs through the consumption of food or water contaminated with the parasite. According to the CDC, the illness is generally not life-threatening and is less common than other foodborne illnesses like salmonella or E. coli. Some infected individuals may not show any symptoms.
Transmission is exclusively fecal-oral, occurring via ingestion of contaminated food or water. Person-to-person transmission does not happen, according to Dr. Caitlin Rivers of the Johns Hopkins Center for Health Security.
Investigating the Source
The specific source of the current outbreak has not yet been identified. Investigations into contamination typically focus on the farm or irrigation level, which can complicate traceback efforts. Past outbreaks in the U.S. and Canada have been linked to various raw produce items, including bagged salad mixes, fresh cilantro, basil, raspberries, snow peas, and green onions.
Preventative Measures
In response to the rising case numbers, Michigan’s health department has advised restaurants and food preparers to mitigate risks associated with raw produce. Recommendations include thoroughly washing greens, cooking raspberries and leafy greens when possible, and removing the outer layers of lettuce and green onions. While the U.S. Food and Drug Administration suggests rinsing produce may not be effective, the CDC continues to recommend it.
Individuals experiencing diarrhea are encouraged to consult a healthcare provider and inquire about potential cyclosporiasis infection.
Steve Lopez is the Editorial Page Editor for News Raise. He covers Health. He has won more than a dozen national journalism awards for his reporting and column writing at seven newspapers and four news magazines.
