A severe stomach bug continues to spread around Michigan with the state now reporting more than 700 cases, although it hasn’t been reported in Berrien County lately.

Cyclosporiasis is caused by a parasite that typically spreads via fresh produce. It started appearing in southeast Michigan, but has now spread to counties as far away as Shiawassee and Jackson.

Berrien County Health Officer Guy Miller tells us the illness has been recorded in Berrien County in the past, but not this year.

“We’ve not had any cyclosporiasis cases in Berrien County, any individuals that have reported cyclosporiasis, and that’s through laboratory confirmation,” Miller said. “We haven’t had any of those this year in 2026. In 2025, we did have two cases. In 24, we had a case. And in 2023, we had two cases.”

Miller says health officials will usually see the illness in those who have traveled overseas and been exposed to food or water not up to U.S. safety standards. As far as the current outbreak, he says it can be difficult to pinpoint the cause of an illness like this because a person can be exposed to cyclosporiasis and not experience symptoms for up to two weeks. Tracking the exact cause means investigating everything patients may have eaten around the time of exposure.

“Our food systems are very complicated, and then we’re relying on people to be the best food historians of where they went and what they ate. So if you went and you got a salad at your favorite restaurant, we would track down that restaurant, figure out where their supplies came from, and sometimes they’re supplying from multiple different locations. So if you had a salad with cucumbers and raspberries and obviously lettuce and cheese on it, we’re trying to track down where all of those different products have come from and trying to see if there is a common source between you and maybe your friend down the street who got the same infection.”

Miller told us more about how cyclosporiasis works.

“The parasite itself, cyclospora, infects the small intestine and causes frequent, watery, and explosive diarrhea. The time between being exposed and becoming sick is usually about one week. It can range from two days to two weeks, but we usually see it one week after you were exposed. So untreated illnesses can last for a few days to actually a few months, and symptoms may go away and then come back later. So it is treatable. It’s usually not life-threatening, but obviously with diarrhea illness, dehydration is a major concern. So making sure that if you are having that illness, that you’re staying hydrated, seeking a healthcare provider. It can last up to two months if you don’t clear the parasite.”

Although there have been no cases reported in Berrien County this year, Miller says the health department does routinely watch out for cyclosporiasis.

“We’re watching for it for a reported diarrhea illness. So, if people call into the health department, they say, ‘I went somewhere and I don’t feel well. This is where I went, what I ate, and these are my symptoms.’ We’ll help coordinate that. Obviously, testing is the biggest thing we really need to figure out, what’s going on and how it should be treated.”

Miller adds a way to protect yourself from cyclosporiasis is to heat foods past 158 degrees Fahrenheit. Also be sure to wash all fresh produce.

You can learn more about cyclosporiasis right here.