Cyclospora outbreak tops 1,700 confirmed cases, Michigan hardest hit
More than 1,700 Cyclospora infections have been confirmed across the United States, with Michigan reporting over 1,560 cases, while health officials continue to investigate the source.
U.S. health authorities are investigating a Cyclospora outbreak that has produced over 1,700 confirmed infections nationwide, with an additional 1,500 cases pending verification. Michigan accounts for the largest share, confirming more than 1,560 cases and 36 hospitalizations, far exceeding its typical annual count of about 50.
Four other states have reported over 100 cases each: Ohio counties bordering southeast Michigan have logged more than 500 cases, New York 394, North Carolina 110, and Illinois roughly 150. The Centers for Disease Control and Prevention (CDC) has recorded 843 cases in 31 states since May 1, noting that state reports are likely higher and that numbers are being updated as confirmations come in.
Cyclospora cayetanensis, the parasite that causes cyclosporiasis, spreads through contaminated food or water, often linked to imported fresh produce such as raspberries, basil, snow peas, mesclun lettuce and cilantro. The parasite originates in fecally contaminated water and can be transferred to crops via irrigation or handling by workers who have not washed their hands. The incubation period is one to two weeks, making source tracing difficult.
"Cyclospora is not transmitted from person to person," said Dr. Jade Le, infectious-diseases service line chief at Access TeleCare.
Symptoms include watery diarrhea, fever, abdominal cramps, nausea and vomiting, and can persist for weeks. Dehydration is the primary health risk, though mortality is rare when medical care is sought.
Public health guidance advises washing fruits and vegetables under running water, cooking produce when possible, and avoiding untreated water. Hand hygiene before and after food preparation is also emphasized. The CDC and other agencies recommend discarding damaged produce and following standard food-safety practices.
"If you develop watery, explosive diarrhea with stomach cramps and low-grade fever, contact a health-care provider promptly," Dr. Le advised.
Diagnosis requires stool testing specifically for Cyclospora, which may need multiple samples. Treatment and prevention measures are being communicated as officials continue to search for a definitive source.