- The CDC is investigating 145 cases of cyclosporiasis in 17 states, but the source of the gut-wrenching outbreak is unknown.
- The outbreak is likely far larger than the federal count. Michigan has reported more than 150 cases in seven counties.
- CDC urges thorough washing of fruits and vegetables under running water and scrubbing firm produce.
The Centers for Disease Control and Prevention is investigating the source of a cyclosporiasis outbreak it said sickened at least 145 people in 17 states. The illness is an aggressive intestinal condition that is caused by a parasite.
The case count, per the CDC, is from May 1, 2026 to June 16, 2026, but is an undercount because some people likely recover without seeking medical care. When it is identified in a clinical setting, the illness is reportable to public health officials in 47 states.
And several state health departments are reporting higher numbers than the official CDC count so far. For instance, the Detroit Free Press reported this week that “more than 150 people in 7 Michigan counties” have become ill due to the parasite. And Michigan was not part of the CDC’s original 17 states.
CDC data shows that those sick from cyclosporiasis acquired in the U.S. ranged in age from 5 to 86. While no deaths were reported, 20 were hospitalized.
None of the 145 people had traveled outside the country recently, meaning their illness was acquired within the U.S. Cases have been confirmed in Alaska, Colorado, Connecticut, Florida, Georgia, Illinois, Louisiana, Massachusetts, New Jersey, New York, North Carolina, Ohio, Pennsylvania, Tennessee, Texas, Virginia and Wisconsin.
New York and Michigan seem to have been hardest hit.
There have also been 45 cases as of June 16 in “people who ate or drank food or water that made them sick while they were traveling outside the United States during the 14 days before they got sick.” Those folks ranged in age from 17 to 89. Among those, three were hospitalized.
About cyclosporiasis
The Monroe (Michigan) County Health Department issued a news release this week outlining cases within the last week, which would not have been included in the CDC surveillance yet, noting that “investigations are underway to identify a potential common exposure.”
The notice asks those who become ill to seek care for stool testing and treatment.
The illness, which causes severe diarrhea, is caused by the parasite Cyclospora cayetenensis, “commonly found in developing countries” and spread by food or water that has been contaminated with feces. It notes U.S. outbreaks have often resulted from contamination in fresh produce.
The illness does not spread person to person.
Symptoms occur within two to 14 days of consuming contaminated food or drink. They include:
- Frequent bouts of watery diarrhea
- Weight loss and diminished appetite
- Stomach cramps and bloating
- Nausea, though vomiting is less common
- Low-grade fever
The health department notes that symptoms can disappear and reappear if the parasite is not treated. And symptoms may last from a few days to more than one month.
Avoiding cyclosporiasis
The CDC reports that how the microscopic parasite gets into food and water is unknown, but urges people to avoid consuming food or drink that might be contaminated. When traveling in places where the illness is endemic “such as tropical and subtropical regions,” the CDC emphasizes that routine chemical disinfection of sanitization practices likely won’t kill Cyclospora.
So hygiene becomes very important, both in those regions and here in the U.S.
The public health giant says to wash your hands with soap and water before handling or preparing raw fruit and vegetables. Then wash those thoroughly under running water before eating, cutting or cooking them. That’s already been done for fruit and vegetables labeled “pre-washed.”
It’s also important to scrub firm fruits and vegetables including melons and cucumbers with a clean product brush. And damaged or bruised areas should be cut away before preparing and eating fresh fruit and vegetables.
Within two hours, cut, peeled or cooked fruit and vegetables should be refrigerated. Sooner is even better.