Cyclosporiasis Cases Rise in U.S. as Officials Investigate Possible Food Source
Public health officials are monitoring a rise in cyclosporiasis cases in the United States, with hundreds of infections reported since May across multiple states. The illness is caused by Cyclospora cayetanensis, a parasite that can contaminate fresh produce and vegetables. While the infection is rarely fatal, it can cause prolonged gastrointestinal symptoms, including watery diarrhea, abdominal discomfort, and recurring bouts of illness that may last for days or weeks.
Michigan has reported a particularly large increase, with more than 700 cases under investigation, according to state health officials. The state typically records about 40 to 50 cases in an average year. Officials began investigating after doctors reported infections in people who had not recently traveled abroad, where the parasite is more commonly found.
Investigators are interviewing patients about restaurants, grocery purchases, and foods they consumed in an effort to identify a common source. So far, no specific grower, supplier, or food product has been publicly linked to the outbreak.
Cyclospora spreads through food or water contaminated with human feces. Experts note that poor sanitation in agricultural fields or contaminated rinse water can contribute to outbreaks. Warm and humid conditions may also support the parasite’s survival.
Diagnosis can be delayed because symptoms may take up to two weeks to appear, and routine stool tests do not always include Cyclospora. Doctors may need to order a specific test. Treatment is often not required for healthy individuals, though antibiotics may be used for people at higher risk or those with persistent symptoms.
Health experts recommend reducing risk by thoroughly washing produce, choosing items that are easier to clean, and cooking vegetables when possible. Leafy greens, herbs, berries, and other produce with uneven surfaces may be harder to clean completely. Federal agencies inspect domestic and imported produce, but officials say stronger sanitation practices throughout the food supply remain important for prevention.