cyclosporiasis surge – Cyclospora infections have sickened 150 people across seven Michigan counties since June 22, with 14 hospitalized, as the CDC tracks hundreds of cyclosporiasis cases nationwide after May 1. Health officials say there’s no confirmed single multistate outbreak,
The first signs of trouble appeared on June 22 in Michigan. Within days. the case count began climbing fast—so fast that by July 1 the state health department said “more than 170 cases” had been reported. By the time this summer’s holiday weekend arrived. Michigan officials were contending with a cluster that has already more than tripled its total case count compared with 2025.
The illness spreading through the state is cyclosporiasis, a parasitic infection tied to contaminated produce. The federal picture shows a broader seasonal surge: since May 1, more than 17 U.S. states have reported cyclosporiasis cases. with the CDC tracking 145 illnesses linked to eating food in the United States and an additional 45 illnesses in people who became infected while traveling abroad. The CDC also says it has no evidence of a single, multistate Cyclospora outbreak connecting cases being reported right now.
At the center of the scramble is one stubborn reality: even when officials can’t yet point to one common source, people still get sick—especially after warm-weather foods make their way onto dinner tables and picnics.
On June 2. the CDC said it had “no evidence of a single. multistate Cyclospora outbreak linking cases happening right now and being reported in press.” The agency said the surveillance numbers on its website are “a surveillance count of cases across the United States of people with cyclosporiasis.” That total. the CDC explained. includes clusters currently under investigation by the Food and Drug Administration and cases that have not been linked to a common source.
Michigan is where the impact has been clearest. The state reported that 150 people have become ill across seven Michigan counties since June 22, and 14 of them were hospitalized. No deaths were reported in the CDC’s nationwide dataset.
Those nationwide figures come with details meant to help readers understand who is most at risk. As of June 16. 145 people across 17 states contracted cyclosporiasis after eating food in the United States. while 45 more were tracked separately after contracting it while traveling abroad. Among the 145 U.S. cases, 20 were hospitalized and none died. Cases involved people ages 5 to 86, with a median age of 42.
The CDC describes a predictable seasonal window. The “season,” meaning the months when the U.S. typically sees a spike in cyclosporiasis, begins May 1 and lasts through the end of August.
The human toll is not confined to one set of counties, but the timing can make it feel personal. Michigan’s first case discovery on June 22 came ahead of the July holiday. From there, the state reported a sharp acceleration, from about 50 cases statewide last year to more than 170 cases by July 1.
To understand what families are dealing with, it helps to know the illness itself. Cyclosporiasis is caused by the parasite Cyclospora cayetanensis. often shortened to Cyclospora or simply “cyclospora.” It typically spreads through contaminated food and produces gastrointestinal symptoms that many people associate with food poisoning—watery. frequent. and sometimes “explosive” diarrhea. along with nausea and vomiting.
The CDC and Cleveland Clinic list other symptoms as well: loss of appetite; bloating, including burping and gas, or stomach cramps; extreme tiredness (fatigue); fever; nausea; and vomiting.
People often ask when they’ll feel sick after exposure. The CDC says the illness can strike about a week after exposure, though symptoms can appear as soon as two days and as late as two weeks later.
Treatment is available, but timing matters. The infection is treated with antibiotics. and while most healthy people can likely recover on their own. prolonged and untreated illness can last for months and recur. according to the CDC. The agency also warns that children. older people. and those with compromised immune systems are more likely to become severely ill—and should contact a health care professional if they get sick.
Warm-weather timing also plays a role in why produce can become a pathway for transmission. Cyclosporiasis spreads via a fecal-oral route. meaning infected fecal matter can contaminate foods. drinks. and surfaces. and illness can follow when that contamination reaches the mouth—often when hands aren’t washed after using the bathroom.
Health officials point to the seasonal pattern: the CDC says infections often rise during warm summer months as infected fecal matter ends up on fresh produce like basil. raspberries. and lettuce. The CDC also notes that produce-linked spikes are common even though outbreaks are more frequent in tropical or subtropical regions of the world such as Central America. South America. and Africa.
Michigan Health and Human Services previously told the Detroit Free Press that contaminated and unwashed produce tends to drive these warm-weather spikes in the United States.
The CDC’s guidance focuses on practical steps that can be difficult to keep straight during busy holiday cooking. Among the recommendations from the CDC, the Cleveland Clinic, and Michigan Health Department:
Avoid consuming food or water that may be contaminated with feces. Avoid drinking or cooking with untreated water.
Wash your hands with soap and water after using the bathroom and before, during, and after food preparation.
Wash all food prep surfaces, including utensils, cutting boards, and countertops, before and after use.
Wash and peel vegetables before eating them; scrub produce with skins like melons and cucumbers well; and cut away damaged or bruised areas on fruits and vegetables before preparing and eating them.
Refrigerate prepared fruits and vegetables as soon as possible—within two hours.
The CDC tracks where infections were contracted. The states included in the CDC’s surveillance map as of June 16 are Alaska. Colorado. Connecticut. Florida. Georgia. Illinois. Louisiana. Massachusetts. Michigan. New Jersey. New York. North Carolina. Ohio. Pennsylvania. Tennessee. Texas. Virginia. and Wisconsin.
For readers trying to connect the dots between national surveillance and local danger. the message from officials is consistent: the cases are being monitored closely. and investigations are underway. but the CDC has not confirmed that there is one single multistate outbreak linking the current cases.
One practical takeaway is harder to ignore as the calendar turns. Even without a confirmed single source, cyclosporiasis is showing up in the exact window that families plan for outdoor meals. And in Michigan. the pace of illness since June 22 has already rewritten how big this summer’s risk looks compared with the year before.
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