Michigan Cyclospora Outbreak Tops 3,000 Cases as Investigators Focus on Leafy Greens
Health officials say the source has not been confirmed, but lettuce and other salad greens remain leading suspects as Michigan experiences its largest cyclosporiasis outbreak on record.
LANSING, Mich. — Michigan health officials are investigating the state’s largest recorded outbreak of cyclosporiasis after suspected cases climbed above 3,000, with evidence increasingly pointing toward contaminated lettuce or other leafy greens as the likely source.
The Michigan Department of Health and Human Services (MDHHS), working alongside the U.S. Centers for Disease Control and Prevention (CDC) and the U.S. Food and Drug Administration (FDA), has interviewed more than 1,000 people as investigators work to identify the exact food item responsible. Officials have not identified a specific grower, supplier or brand, and no statewide recall has been announced.
The outbreak has spread beyond Michigan, with more than 30 states reporting cases this year. Nationally, 2026 has already surpassed the previous U.S. record for reported Cyclospora infections set in 2019, according to the Associated Press.
Some Taco Bell restaurants in Michigan have temporarily removed fresh ingredients such as lettuce from their menus as a precaution. Federal and state investigators are examining whether some illnesses may be associated with meals eaten at Taco Bell locations, but officials stress that no direct link has been confirmed and the investigation remains ongoing. The FDA has not announced a recall involving Taco Bell.
Cyclosporiasis is caused by the microscopic parasite Cyclospora cayetanensis. People typically become infected by consuming food or water contaminated with the parasite. Unlike many stomach illnesses, Cyclospora generally is not spread directly from person to person because the parasite requires time in the environment before becoming infectious.
Symptoms often begin about a week after exposure and can include:
Watery diarrhea
Loss of appetite
Stomach cramps
Nausea
Fatigue
Bloating
Weight loss
Without treatment, symptoms can last for weeks or even return after temporarily improving. The illness is usually treated with the prescription antibiotic trimethoprim-sulfamethoxazole (TMP-SMX), along with fluids and rest.
Health officials are urging anyone experiencing prolonged diarrhea to seek medical care and request testing specifically for Cyclospora, as routine stool tests may not detect the parasite. Residents are also encouraged to thoroughly wash fresh produce, although experts note washing alone may not completely remove the parasite.
As investigators continue tracing the source, MDHHS says consumers should not panic or stop eating fresh produce altogether, but should remain aware of symptoms and follow food safety recommendations until the investigation is complete.