Michigan cyclosporiasis outbreak nears 1,000 cases as Ohio infections rise

Michigan health officials say the state’s cyclosporiasis outbreak has climbed to 992 cases, putting it within reach of 1,000 infections as investigators continue to search for the source. At the same time, health officials in Ohio are reporting a sharp rise in cases, adding to concern that the outbreak may be part of a linked multistate spread.

About 40 people in Michigan have been hospitalized, according to reporting based on state officials. No deaths have been reported. The Michigan Department of Health and Human Services says the outbreak source has not been identified.

Michigan’s outbreak climbs

MDHHS says the case count is updated daily and reflects reports through 9:30 a.m. Eastern time. As of July 8, the state’s total stood at 992 cases.

Michigan officials first announced the outbreak on July 1, when they knew of more than 170 cases in the southeastern corner of the state dating back to June 22. The state then continued issuing daily updates as investigators worked to trace the illness.

By July 4, MDHHS had also posted additional foodborne-illness prevention guidance for restaurants and kitchens handling raw produce.

AP has reported that Michigan typically identifies about 50 cyclosporiasis cases a year, underscoring how unusual the current outbreak is.

Ohio cases raise the stakes

The Associated Press reported that Lucas County, Ohio, had 306 cases as of Wednesday, with more than 500 cases reported in northwest Ohio. Michigan chief medical executive Natasha Bagdasarian told AP there is “clearly a linked outbreak happening right now.”

That spillover matters because it suggests investigators may be dealing with a shared contamination source rather than a single local problem. Officials have not said whether the Michigan and Ohio cases are all part of one outbreak or whether multiple clusters are involved.

Ohio health officials are still trying to determine whether the rise is tied to the Michigan outbreak or reflects separate cases. The distinction will shape any traceback effort aimed at finding the contaminated food, grower, distributor or other source.

Why cyclospora is difficult to solve

Cyclosporiasis is caused by the Cyclospora parasite and typically spreads through contaminated food or water. Public-health investigators often have a hard time identifying the source because the parasite can be difficult to detect and does not grow in labs.

That makes outbreaks slower to unravel than many other foodborne illnesses. Officials have to piece together illness histories, food purchases and distribution patterns before they can narrow the likely source.

MDHHS has told people with ongoing gastrointestinal illness to contact a health care provider and their local health department. The agency has also issued precautions for restaurants and kitchens handling raw produce, including leafy greens, cilantro, basil, green onions, raspberries and snow peas.

What investigators are watching

The key unanswered question remains the same: what food or supplier is driving the outbreak. Investigators are watching for a specific produce item or distribution chain that could explain why cases continue to rise in Michigan and appear in Ohio.

Officials are also waiting to see whether the Centers for Disease Control and Prevention or the Food and Drug Administration issues a formal multistate update. For now, the outbreak remains active, the source remains unidentified and daily counts in Michigan continue to move upward.