A parasitic intestinal illness has exploded across southeast Michigan at a pace that state health officials have never seen before — and it is still growing.
As of July 6, 681 cases of cyclosporiasis have been reported in Michigan since June 22 — more than 13 times the state's typical full-year count. "Michigan typically identifies 50 cases a year," MDHHS spokesperson Laina Stebbins confirmed. By July 7, Today.com reported the count had climbed to more than 708 and is expected to continue rising.
In Michigan, cases rose from 170 on June 30, to 572 by July 4, with the highest cluster of cases coming from southeast Michigan. The outbreak now spans eight southeast Michigan counties — Monroe, Lenawee, Washtenaw, Wayne, Shiawassee, Jackson, Oakland, and Livingston — and has spread into northwest Ohio, with cases confirmed across 43 counties statewide there, according to ABC News. At least 110 Cyclospora infections have also been reported in North Carolina.
Why This Matters
The human cost of this outbreak is immediate and personal. Monroe County resident Haley Hompstead described being woken by "the most excruciating abdominal pain" in the early hours of July 3. Her account reflects what hundreds of Michigan families have now experienced: a sudden, severe gastrointestinal illness with no obvious explanation and no recalled product to avoid.
As of July 4, 2026, no specific produce grower, supplier, or specific produce type has been identified as the source of the outbreak, the Michigan Department of Health and Human Services said. Dr. Natasha Bagdasarian, MDHHS chief medical executive, described the case count as a "moving target" and confirmed investigators' working hypothesis is that the outbreak is linked to contaminated produce.
Without a specific recall, the burden falls on individual households to follow produce safety practices — and on clinicians to suspect and test for this parasite when patients present with the right symptoms.
What We Know So Far
On July 6, MDHHS received 681 reports of cyclosporiasis since June 22. The cases remain highest in Monroe, Lenawee, Washtenaw, Wayne, Shiawassee, Jackson, Oakland, and Livingston counties. MDHHS is working on finding a direct cause.
The CDC is working with the FDA and local health officials to investigate clusters across multiple states. The CDC says those infected became sick after eating food in the U.S., and none reported traveling internationally in the weeks prior. Currently, there is "no evidence of a single, multi-state Cyclospora outbreak linking all cases," the CDC said in an update on July 1.
Nationally, the CDC has confirmed 145 cyclosporiasis cases in 17 additional states as of June 16 — a count that does not include Michigan's cases.
The age range of patients in Michigan spans 8 to 84, with a median age of 41. "Though in most cases this illness causes discomfort from cramping, bloating and watery diarrhea, we are concerned about individuals who may be immunocompromised due to cancer treatment or an organ transplant as the effects may be more severe," said Lynn Sutfin, public information officer for MDHHS.
Where the Risk Is Highest
The eight-county cluster in southeast Michigan remains the primary outbreak zone in the United States right now. Monroe County has the highest case count. Within Michigan, the illness has been reported in people ages 8 to 84 across both urban and suburban settings.
The geographic spread into Ohio confirms that the outbreak is not limited by county or state lines. The Michigan Department of Health and Human Services said cases in southeast Michigan jumped 29 percent in just four days — a growth rate that suggests the exposure is ongoing.
In the U.S., cyclosporiasis outbreaks have been linked to fresh fruits and vegetables, including basil, cilantro, raspberries and snow peas, per the CDC. In 2022, a large cluster of cases in Florida was attributed to a Caesar salad kit containing bagged romaine lettuce.
What Doctors and Experts Say
Dr. Irfan Hafiz, an infectious disease physician at Northwestern Medicine, told NBC Chicago that some people may also contract such infections from swimming in lakes, ponds, or waterparks.
Dr. Hafiz described what makes Cyclospora different from other stomach bugs: "The symptoms are a bit less, but they go on longer. Noroviruses kind of hit you hard and then it's done. This kind of just drags on for a longer period of time."
The key clinical warning for healthcare providers: standard stool cultures do not detect Cyclospora. A modified acid-fast stain or Cyclospora-specific PCR must be specifically ordered. Physicians and healthcare providers are urged to consider cyclosporiasis among patients presenting with acute gastrointestinal illness in southeast Michigan.
What the Evidence Shows — and What It Does Not
MedicalDaily Evidence Check
- Data source: Michigan MDHHS; CDC
- Michigan confirmed cases: 681 as of July 6, 2026; 708+ as of July 7
- Michigan typical annual total: 50 cases
- Age range: 8 to 84; median age 41
- Food source: Not yet identified; investigation ongoing
- What it shows: A major, rapidly growing parasitic outbreak significantly exceeding baseline
- What it does not show: A specific recalled product or confirmed source
- What readers should know: No single food product has been identified; current protection depends on produce hygiene and seeking medical care if symptoms develop
Who Faces the Greatest Risk?
MDHHS said the recommendations are especially essential for people who have a higher risk of dehydration or weakened immune systems, such as patients on chemotherapy, organ transplant recipients, infants and young children, and elderly people.
Adults and children who consumed bagged salad mixes, pre-cut leafy greens, cilantro, basil, or other fresh produce in the affected counties since mid-June face the broadest potential exposure. Anyone with a recent negative standard stool test who has had prolonged diarrhea should request a Cyclospora-specific test.
Symptoms and Warning Signs to Watch For
Symptoms occur two to 14 days after exposure and may include: frequent watery diarrhea; loss of appetite and weight; abdominal cramps and bloating; nausea (vomiting is less common); and low-grade fever.
"Without treatment, symptoms can last anywhere from a few days to a month or longer," the CDC states. "Some symptoms, such as diarrhea, may go away and then return."
What You Can Do Now
MDHHS issued new produce preparation guidance on July 6. Health officials said to take the following steps to reduce the risk of exposure:
- Lettuce/leafy greens : Buy whole heads of lettuce rather than pre-washed, bagged lettuce or salad mixes. Throw away the outer 2–3 leaves and wash the inner leaves under running water.
- All produce : Wash all fresh produce under clean running water, even if you plan to peel it.
- Cilantro and basil : Wash thoroughly under running water, separating the leaves.
- Cook when possible. Heating food to 158°F (70°C) or higher kills Cyclospora.
- If you develop prolonged or recurring watery diarrhea, see your healthcare provider and specifically ask for a Cyclospora test — not just a routine stool culture.
Cost and Access: What Patients Should Know
The treatment for cyclosporiasis — trimethoprim-sulfamethoxazole, sold as Bactrim, Septra, or Cotrim — is a generic antibiotic taken orally for 10 days. It is available at most pharmacies at low cost with or without insurance. A GoodRx discount typically brings the price under $10.
What Happens Next
MDHHS and the Michigan Department of Agriculture and Rural Development (MDARD) are investigating food suppliers linked to the outbreak. The CDC continues to coordinate with state agencies nationally. Case counts are expected to continue rising. MedicalDaily will report immediately when a food source is confirmed or a recall is issued.
The Bottom Line
681 Michiganders have been diagnosed with a parasitic infection in two weeks — 13 times the state's annual baseline — with no food source identified. MDHHS issued new produce guidance on July 6. If you live in southeast Michigan and have experienced prolonged, recurring diarrhea since late June, see a doctor and ask specifically for a Cyclospora test.
