A stomach-churning parasite is spreading in the country, causing weeks of diarrhea, cramps, and bloating.
Cyclosporiasis has been found in Michigan at a rate 13.5 times higher than normal, or about 700 cases confirmed in the state. Most have been found in the southeast area, ABC News reported.
But Michigan is not alone.
As of the Centers for Disease Control and Prevention’s most recent data of June 16, there were cases in 17 states.
The CDC said that cases typically increase in the spring and summer, but that the agency tracks cases year-round.
Ohio had 117 cases of the infection this year, with most — 171 — coming in June, CNN reported.
According to the CDC's 2026 case map, an estimated 1-10 cases of cyclosporiasis have been reported in both Massachusetts and Connecticut. No other New England states have had reported cases.
Cyclosporiasis cause
The CDC said cyclosporiasis is caused by the microscopic parasite Cyclospora cayetanensis, which can be contracted by consuming contaminated food or water.
It can take from two days to two weeks or more for the symptoms to develop.
Symptoms
Some people may not have any symptoms if they’re infected with the parasite, but others aren’t as lucky.
It infects the small intestine and can cause watery diarrhea with frequent or explosive attacks.
If not treated, it can last a few days to over a month, the CDC said. The symptoms can also come and go.
Symptoms include:
- Watery diarrhea (most common)
- Loss of appetite
- Weight loss
- Cramping
- Bloating
- Increased gas
- Nausea
- Fatigue
Other symptoms include:
- Vomiting
- Body aches
- Headache
- Low-grade fever
- Other flu-like symptoms
Treatment
Typically, cyclosporiasis is treated with trimethoprim-sulfamethoxazole, sold under the names Bactrim, Septra, or Cotrim.
Patients should also drink plenty of fluids and rest.
Most people will recover without treatment, but people who are immunocompromised may be at higher risk of severe or prolonged illness, the CDC said.