Michigan has recorded 708 cyclosporiasis cases in about 10 days, a jump that has pushed the state far beyond what health officials normally see and sent investigators racing to find the source. More than 700 cases were confirmed over the last few weeks, and patients in Ohio, North Carolina, Illinois and New Jersey have also reported illness.
The illness, cyclosporiasis, is caused by the microscopic parasite cyclospora and often brings explosive, watery diarrhea, stomach cramps, nausea and loss of appetite. It does not spread from person to person, but it can linger for weeks if untreated and some people have needed hospital care because of dehydration.
That surge is why people are searching for answers now. Michigan usually sees only 40 to 50 cyclosporiasis cases a year, and health officials say summer is the season when infections rise, especially between May 1 and Aug. 31. Natasha Bagdasarian said staff were pulling people’s grocery shopping lists and working overtime as cases climbed, a sign of how quickly the outbreak has strained the response.
The Food and Drug Administration said its investigation into the source is ongoing, and the FDA and the Centers for Disease Control and Prevention are monitoring the outbreaks. But the picture is not as tidy as the case counts suggest. The CDC said it has no evidence of a single, multistate Cyclospora outbreak tying together the illnesses now being reported, even as cases continue to surface in several states.
That gap matters because cyclosporiasis almost always traces back to fresh produce, and past outbreaks have involved raspberries, bagged lettuce or salads, cilantro and basil. Without a source, the cases can keep rising while the search narrows by the day. Dr. Brian Kaminski said cases in southeastern part of Michigan and northwest Ohio appear to be part of an epidemic cluster, and he said the trend continues, while ProMedica Health System had accounted for 411 cases as of Monday.
The CDC said 145 cases in 17 states were reported from the beginning of May through June 16, and in July 2025 it made tracking cyclospora optional as part of scaling back its Foodborne Diseases Active Surveillance Network. For now, that leaves investigators trying to piece together a fast-moving foodborne illness from grocery lists, lab results and patient interviews, while the specific food behind the surge remains unknown.
