Michigan reports over 1,500 cyclosporiasis cases as health officials issue safety guidance

The Michigan Department of Health and Human Services (MDHHS) announced Thursday that 1,562 cases of cyclosporiasis have been confirmed in the state since June 22, up from 1,251 the day before, with 44 hospitalizations reported. The outbreak is concentrated in Monroe, Lenawee, Washtenaw, Wayne, Shiawassee, Jackson, Oakland and Livingston counties, and investigators are still working to identify the source.

"Anyone experiencing gastrointestinal illness, such as sudden and ongoing diarrhea, should contact their health care provider and their local health department," MDHHS said in a statement.

Cyclosporiasis is an intestinal infection caused by the parasite Cyclospora, diagnosed through stool testing. Symptoms include watery diarrhea that can last from several days to more than a month and may recur. The incubation period typically ranges from two days to two weeks.

Health officials noted that past U.S. and Canadian outbreaks have been linked to fresh produce such as bagged salad mixes, cilantro, basil, raspberries, snow peas and green onions. MDHHS issued preparation recommendations on July 6, urging consumers to buy whole heads of lettuce instead of pre-washed mixes, discard outer lettuce leaves, and wash all produce under running water. Cooking leafy greens, herbs and other listed items to at least 158 °F (70 °C) is described as the most reliable way to eliminate the parasite.

The agency emphasized that these measures are especially important for individuals at higher risk of dehydration or severe illness, including patients undergoing chemotherapy, organ-transplant recipients, infants, young children and older adults. General food-safety reminders also include washing all fresh produce, even if it will be peeled, and cooking foods when possible.