Michigan recorded 10,386 cases of cyclosporiasis, an increase of 309 from the 10,077 reported one day earlier, as state and local health officials continued investigating a large outbreak of the intestinal illness. Thirty-three additional residents required hospital care during the latest weekly reporting period, bringing hospitalizations to 193.
The Michigan Department of Health and Human Services began tracking the outbreak on June 22. It was first identified in Monroe County and subsequently reached 70 counties, with southeastern Michigan carrying the largest burden. Wayne County reported more than 1,000 cases. Eaton, Genesee, Ingham, Lenawee, Monroe, Oakland, Shiawassee, Washtenaw and Wayne each reported more than 300.
Michigan typically records about 50 cases in a year. During this outbreak, totals were increasing by hundreds per day. The July 27 number included roughly 475 cases that laboratories had reported late, showing that daily changes reflected both new detection and delays in the reporting system. The state published case figures each weekday and updated hospitalization data on Thursdays.
Cyclosporiasis is caused by Cyclospora cayetanensis, a parasite spread when faecal contamination reaches food or water. Common symptoms include frequent watery diarrhoea, reduced appetite, bloating, nausea and fatigue. Body aches, headache and vomiting can also occur. Illness often begins around one week after infection and may persist or return for weeks without treatment.
State officials had identified lettuce or salad greens as a possible source on July 13 while leaving other foods under consideration. On July 24, the Centers for Disease Control and Prevention linked a lettuce supplier serving Taco Bell to part of the outbreak. Federal officials also said several distinct clusters were active nationwide, meaning one supplier or food could not automatically explain every Michigan case.
Wayne County Public Health began contacting residents with a survey to gather food histories and other information. The agency asked selected people to respond so investigators could narrow possible exposure routes and protect the wider community.
Officials did not announce a final source for all cases or state that transmission had ended. The sharp daily additions, expanded geographic reach and rising hospital count instead described an ongoing event. Distinguishing laboratory-reporting delays from newly emerging illness, and separating any Taco Bell-associated cluster from unrelated infections, remained necessary for interpreting the statewide total. The 10,386 count therefore marked a reporting threshold, not the conclusion of the investigation.
The gap between onset, testing and notification is especially important for a parasite whose symptoms can start about a week after exposure. Hospital totals also update less frequently than case counts. As a result, figures released on the same date may describe different reporting windows and should not be used to calculate a same-day hospitalization rate.
