Cases of food poisoning caused by a parasite that causes explosive diarrhea continue to spread across the United States, reaching above 700 in Michigan in the week after July 4.
Cyclosporiasis, a stomach-churning disease caused by a parasite often found on produce, has sickened hundreds of people in more than 18 U.S. states since May 1, according to the Centers for Disease Control and Prevention and state health data. Michigan is battling a cluster of infections that has already more than tripled the total case count by 2025, while several others have reported numbers above 100.
Additional state-level reporting shows a large increase of cases not yet reflected on the CDC surveillance dashboard, which is updated monthly. The latest data, published on June 16, has yet to capture the rapidly growing spread.
Currently, there is no evidence of a single, multistate outbreak linking all cases. Local and federal officials are still working to identify the possible source of the disease for disease clusters like the one in Michigan; However, many cases so far appear to be part of a seasonal surge. The CDC considers the annual cyclosporiasis surge to last from May 1 to August 31.
Here’s what to know as the top 1,000 cases rise.
Michigan tops with more than 700 cases
Between June 22 and Monday, July 6, more than 700 cases of cyclosporiasis were reported in Michigan, 36 of which required hospitalization.
“At this time, no specific product producer, supplier or type of product has been identified as the source,” Lynn Sutfin, spokeswoman for the Michigan Department of Health and Human Services, told USA TODAY on July 7.
New York is in second place
A total of 301 cases have been reported in New York City this year as of July 7, the health department told USA TODAY on July 7, with 273 of those cases occurring since May 1. New York City’s count includes people who have recently traveled internationally as well as those who acquired it domestically.
New York state, which reports and tracks infectious diseases separately from NYC, has 120 confirmed cases as of May 1, 2026. The state has reported a relatively high number of cases over the years, rising to above 500-700 across the state in 2024 and 2025.
“Although cyclosporiasis is unlikely to spread directly from person to person, and is not generally life-threatening, as many people with healthy immune systems recover without treatment, the department encourages all New Yorkers to be aware of best practices to prevent cyclospora and other infections occurring during the summer months,” spokeswoman Marissa Crary told USA TODAY in an email July 7.
Ohio sees a surge
The Ohio Department of Health has reported 177 cases in 43 counties so far in 2026. Of those, 171 cases occurred in June, mostly since June 20, ODH spokesman Ken Gordon told the Columbus Dispatch, part of the USA TODAY Network, on July 2.
Gordon told USA TODAY in an email Tuesday, July 7, that updated data is not yet available and will be published each Thursday.
Nearly 150 cases reported in North Carolina
At least 145 cases of cyclosporiasis have been reported in North Carolina between May 1 and July 7, the NCHD told USA TODAY in an email. It was not made clear whether they were all domestically acquired.
Illinois falls out of top five
The Department of Public Health said there were 141 cases of cyclosporiasis reported in Illinois as of July 7, 59 of which were locally acquired and 20 of which are awaiting investigation.
“IDPH is seeing a higher-than-average number of reported cases of cyclosporiasis, similar to what is seen in many other states,” spokesman Matthew Mata told USA TODAY. “At this point, no single source or cause of this increase has been identified, and there is no evidence of widespread spread accounting for all or most of these cases. IDPH continues to work with CDC and other public health partners to look for trends.”
List of states with confirmed cases
As of Tuesday, July 7, the following states have confirmed cases of cyclosporiasis, according to the CDC and local reporting.
- alaska
- colorado
- connecticut
- Florida
- Georgia
- Illinois
- louisiana
- Massachusetts
- michigan
- new Jersey
- new york
- North Carolina
- ohio
- pennsylvania
- Tennessee
- texas
- Virginia
- wisconsin
Caution for foods that caused previous outbreaks
State health departments have issued guidelines to avoid the spread of cyclosporiasis, which is often caused by contaminated, unwashed produce in the summer.
- Avoid consuming food or water that may be contaminated with feces. Avoid drinking or cooking with untreated water.
- Wash your hands with soap and water after using the bathroom and before, during, and after preparing food.
- Wash all food preparation surfaces, including utensils, cutting boards and countertops, before and after use.
- Wash and peel vegetables before eating; Rinse produce with peels, such as melons and cucumbers, thoroughly; And cut off damaged or bruised areas of fruits and vegetables before preparing and eating them.
- Place prepared fruits and vegetables in the refrigerator as soon as possible (within two hours).
- Cook your own meals when possible; Heating food to 158 °F (70 °C) or higher kills Cyclospora.
Although the current cluster of cases has not yet been linked to any single outbreak or common food item, health officials have advised taking extra precautions with foods that have been behind previous outbreaks. The following foods should be washed and scrubbed thoroughly with a brush or sponge.
- Bagged salad mixes and kits (pre-cut salad mix with romaine, iceberg, red cabbage, carrots)
- Fresh Coriander Leaves (Dhaniya Patti)
- fresh basil
- raspberry
- snow peas
- Green Onions (Scallions)
Reporting by Mary Walrath-Holdridge, USA TODAY/USA TODAY. USA TODAY Network via Reuters Connect.