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.
Despite the fatalities, medical experts say the deaths should not cause widespread alarm.
“There is really no reason for alarm,” said Dr. Joel Kammeyer of Wayne State University. “Whereas we don’t know the details, I have to say that I wasn’t incredibly shocked to hear this news.”
Kammeyer added that dehydration caused by the parasite can be especially dangerous for people with multiple health conditions.
“For patients that have multiple medical issues at one time, it may be the case that there might be the occasional patient that’s poorly equipped to withstand the dehydration that cyclosporiasis can lead to,” Kammeyer 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.
Cases across the country
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.
Canadian officials notice increased cases
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.
Symptoms of cyclosporiasis
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.
Tracking the disease
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.
Tips to prevent cyclosporiasis
Michigan health officials shared the following tips for avoiding the illness:
- Wash all fruits and vegetables thoroughly, under running water, before cutting, cooking or eating.
- Scrub firm fruits and vegetables, such as melons and cucumbers, with a produce brush when cleaning.
- Cut away any damaged or bruised areas of produce before preparing and eating.
- Refrigerate any cut, peeled or cooked produce within two hours of preparing it.
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.
Health officials are encouraging residents to continue eating fresh produce while taking steps to reduce their risk of illness.
“We’re continuing to recommend that patients not necessarily avoid lettuce, but wash it at home, peel off the outer layer,” Kammeyer said. “For other fruits and vegetables, make sure that they’re refrigerated, cut out any bruising and cook your vegetables when you can. That’s still thought to be the best advice for everyone.”
Public reaction to the cyclosporiasis outbreak
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.
