In a follow-up on the cyclosporiasis outbreak in Michigan, the Michigan Department of Health and Human Services (MDHHS) reports the number of reported cases has risen to 572 as of Saturday, July 4, up from 170 on Tuesday, June 30, with the largest increase occurring in Southeast Michigan- Monroe, Lenawee, Washtenaw, Wayne, Shiawassee, Jackson, Oakland and Livingston counties.
Health officials say as of July 4, 2026, no specific produce grower/supplier, or specific produce type has been identified as the source of the outbreak.
Given the large and increasing number of cases in Michigan, MDHHS recommends that entities in Southeast Michigan who are preparing, processing, or serving raw produce, including restaurants and other commercial kitchens, take the following steps to reduce risks of exposure:
Lettuce/leafy greens: buy whole heads of lettuce (rather than prewashed, bagged lettuce or salad mixes), throw away the outer 2–3 layers of leaves and wash the inner leaves under running water. For leafy greens that can be cooked, cooking is the safest option.
Cilantro, basil: Wash thoroughly under running water, separating the leaves. Safest when cooked.
Green onions: Trim the root end and remove the outer layer, wash thoroughly under running water. Safest when cooked.
Raspberries: Their bumpy surface makes them especially hard to clean; the parasite can hide in the tiny crevices. Safest when cooked (pies, jams etc.). Consider frozen raspberries as an alternative (freezing may reduce but does not guarantee elimination of the parasite).
Snow peas: Wash under running water and rub the surface. Safest when cooked.
General Rules to Reduce Your Risk
Cook when you can. Heating food to 158°F (70°C) or higher kills Cyclospora.
Wash all fresh produce under clean running water, even if you plan to peel it.
Cyclosporiasis is an intestinal illness caused by the Cyclospora parasite. People can become infected by consuming food or water that contains the parasite. Cyclospora infects the small intestine (bowel) and usually causes frequent, watery and explosive diarrhea. The time between being exposed and becoming sick is usually about one week but can range from two days to two weeks or more. Untreated, the illness may last from a few days to more than a month. Symptoms may go away and then return.
Screwworm 101
Cyclosporiasis is not usually life-threatening, but dehydration from frequent bouts of diarrhea can cause severe illness, particularly among younger or older people and those who have weakened immune systems.