Michigan Cyclospora Cases Surge to 572 While CDC Reports Zero

Suspected cases of a parasitic infection triggering severe digestive distress have skyrocketed to nearly 600, prompting urgent new warnings from health officials. The Centers for Disease Control and Prevention (CDC) reported that 145 Americans across 17 states have contracted the cyclospora parasite from an unidentified source within the U.S., with 20 patients requiring hospitalization. Yet, the situation in Michigan presents a stark and growing anomaly: state officials confirmed that by July 4, the state alone had recorded 572 cases. This figure stands in sharp contrast to the CDC's July 1 update, which listed zero cases for Michigan.

The outbreak appears to be accelerating rapidly. Michigan's Department of Health and Human Services (MDHHS) first disclosed the state's numbers last week, noting a surge from 170 reported cases on June 30 to over 300 by July 3. While the agency is racing to pinpoint the cause and suspects a link to food, no specific grower, supplier, or produce type has been identified yet. Despite this uncertainty, the department has issued immediate directives to restaurants, particularly in Southeast Michigan where the bulk of infections are concentrated, to take aggressive steps to mitigate exposure risks.

Authorities have provided granular instructions for handling produce. For lettuce and greens, the MDHHS urged establishments to purchase whole heads rather than prewashed, bagged mixes, instructing staff to discard the outer two to three layers of leaves and wash the inner ones under running water. Similarly, cilantro and basil must be washed thoroughly and separated, while green onions should be trimmed at the root and have their outer layer removed before washing. Raspberries, with their bumpy surfaces that harbor the parasite in crevices, and snow peas must also be washed under running water. The agency emphasized that heating foods to 158°F (70°C) can kill the cyclospora parasite, and all fresh produce should be washed, even if peeling is intended.

The stakes are high because cyclospora causes cyclosporiasis, an infection characterized by sudden, severe gastrointestinal symptoms including diarrhea, cramping, nausea, vomiting, and fatigue. The Cleveland Clinic warned that this illness, transmitted by the parasite *Cyclospora cayetanensis*, often results in watery, sometimes explosive, diarrhea and other stomach problems. Symptoms typically manifest about a week after exposure to the parasite, which is usually acquired by consuming food or beverages contaminated with feces. Human-to-human transmission remains rare.

Investigations are ongoing at local, state, and federal levels to identify potential sources of these clusters affecting multiple states. However, experts caution that the true scope of the problem may be larger than current reports suggest, as not every infected individual seeks testing or treatment. In the current outbreak, New York is currently experiencing the highest number of cases, with figures ranging between 31 and 80 according to the CDC's latest update this week.

Michigan state officials have confirmed nearly 600 cases of cyclosporiasis, prompting urgent health directives from the Michigan Department of Health and Human Services (MDHHS). The agency stresses that these food safety recommendations are critical for vulnerable populations, including young children, older adults, chemotherapy patients, organ transplant recipients, and anyone at higher risk of dehydration or with weakened immune systems.

The outbreak remains concentrated in Monroe, Lenawee, Washtenaw, Wayne, Shiawassee, Jackson, Oakland, and Livingston counties, where case numbers are highest. MDHHS is coordinating closely with local health departments and the Michigan Department of Agriculture and Rural Development (MDARD), promising to release updated information as new data becomes available. As of July 1, patients within the state range from eight to 84 years old, with an average age of 44.

Without treatment, cyclosporiasis can persist for over a month, causing symptoms to subside and reappear in cycles. The Centers for Disease Control and Prevention (CDC) advises the public to avoid consuming food or water potentially contaminated with feces and to strictly follow general food safety preparation guidelines. Restaurant workers are now under specific orders to thoroughly wash produce, such as lettuce, to mitigate infection risks.

Most individuals with healthy immune systems will recover without medical intervention. However, those suffering from gastrointestinal illness, characterized by sudden and ongoing diarrhea, must immediately contact their healthcare provider and notify their local health department. Treatment for symptomatic patients involves a course of the antibiotic trimethoprim-sulfamethoxazole, available under brand names like Bactrim, Septra, or Cotrim.

The disease typically sees a surge in cases between May and August and often affects people returning to the U.S. after foreign travel. While the CDC reports that New York currently faces the most cases, ranging from 31 to 80, Texas and Illinois follow with between 11 and 30 cases. The remaining 14 states reporting infections each recorded between one and ten cases.

Historically, previous outbreaks have traced back to bagged salad kits, cilantro, basil, and other leafy greens, though officials have not yet identified a specific source for this current outbreak. Additionally, 45 cases of cyclosporiasis have emerged among people who became ill after eating or drinking contaminated food or water while traveling outside the United States. These travelers range in age from 17 to 89 years old. Of this group, three patients required hospitalization, but no deaths have been reported. The CDC has not disclosed the specific destinations of these travelers.