The situation surrounding the explosive diarrhea parasite is looking to get even messier. Health officials are investigating multiple clusters of cyclosporiasis that appear to have no tie to the current largest outbreak traced back to iceberg lettuce from Taylor Farms. On Wednesday, the Food and Drug Administration officially added a new outbreak of cyclosporiasis to its list of active investigations—the third ongoing batch of cases outside the multi-state outbreak that’s sickened thousands so far. Meanwhile, some states like Ohio are still experiencing a rapid surge in new cases, prompting more aid from federal health officials. More than 4,000 confirmed cases of cyclosporiasis across 41 states have been documented this year so far. An explosive problem Cyclosporiasis is caused by the microscopic parasite Cyclospora, primarily Cyclospora cayatenensis. The disease often causes watery and explosively loud bouts of diarrhea, along with other common symptoms of gastrointestinal illness. Though cyclosporiasis cases in the U.S. tend to normally show up in the summer, 2026 has been one for the record books.
The largest outbreak is now thought to be affecting nine states (up from five states previously documented): Kansas, Oklahoma, Illinois, Indiana, Kentucky, Pennsylvania, West Virginia, Michigan, and Ohio. This outbreak has been linked to certain lots of iceberg lettuce distributed by Taylor Farms, which led to a widespread recall.
