Two Michigan residents who had “significant underlying health conditions” have died after contracting cyclosporiasis, the Michigan Department of Health and Human Services said on Monday.
State officials have been providing nearly daily updates over the past few weeks on the cyclospora outbreak, which has sickened thousands of people.
Without going into further details, the health department said both cases involved people with significant underlying health conditions that may have been complicated by cyclosporiasis and dehydration.
“Cyclosporiasis is generally not a life-threatening illness. Death resulting from cyclosporiasis is uncommon in the United States,” Michigan health officials said.
The Michigan Department of Health and Human Services says it has counted 11,234 cases as of Aug. 3, up 461 from the 10,773 cases as of July 31. Tracking of an outbreak of the intestinal ailment began in Michigan on June 22.
Health officials say 193 of those Michigan residents have been hospitalized as of July 30.
The Michigan numbers are different from the CDC’s tally. The CDC says its surveillance updates do not include probable cases, only laboratory-confirmed cases. The CDC works with state officials to update the counts as additional information becomes available.
Michigan normally sees around 50 cases of cyclosporiasis per year, according to MDHHS.
Michigan health officials report case numbers Monday through Friday. Hospital reports are updated once a week on Thursdays.
The Windsor-Essex County Health Unit in Ontario said it is urging its residents to take precautions when traveling to Michigan, given the significant increase in cases of cyclosporiasis.
As of July 31, Windsor-Essex has identified 24 cases of cyclosporiasis in 2026. In a typical year, the region averages only around three cases. “Local public health investigations have identified travel to Michigan as a common exposure among many recent cases,” the county health department said.
Cyclospora cayetanensis is a parasite that causes the diarrheal illness cyclosporiasis. The Centers for Disease Control and Prevention says the most common symptoms associated with the illness are frequent watery diarrhea, loss of appetite, bloating, nausea and fatigue. Some people may also experience body aches, headache or vomiting.
Symptoms typically begin about a week after infection, and remain from about two days to two weeks or longer.
“Without treatment, illness can last for weeks and may come and go,” Wayne County health officials said.
Michigan’s outbreak was first detected in Monroe County in late June and has since spread to 70 counties, with Southeast Michigan bearing the heaviest burden.
Oakland and Wayne counties each have reported more than 1,000 cases. Eaton, Genesee, Ingham, Lenawee, Monroe, Muskegon, Oakland, Shiawassee, Washtenaw and Wayne counties are all reporting more than 300 cases each.
The Wayne County Public Health agency in Michigan said on July 30 that it is reaching out to community residents with a survey to gather more information about the outbreak. “If we contact you, please take a few minutes to answer our questions. Your response helps us identify possible sources of illness and protect the health of our community,” Wayne County Public Health said.
Michigan health officials shared the following tips for avoiding the illness:
Michigan officials said on July 13 that testing pointed to lettuce or salad greens as a potential source, though other foods hadn’t been ruled out.
On July 24, the Centers for Disease Control said a lettuce supplier to fast-food giant Taco Bell has been linked to the outbreak. Taylor Farms voluntarily pulled all of its iceberg lettuce grown in central Mexico from the market.
However, federal officials said there are multiple clusters of the ailment active in the United States.
A CBS News poll from July 26 that four in 10 Americans are buying or eating less produce because of the parasite.
Lettuce sales at supermarkets, along with visits to several food and restaurant chains where popular menu items include lettuce, have also declined since the outbreak began, CBS News found.
The above video originally aired on July 16, 2026.
