WASHINGTON — Federal health officials are tracking a seasonal rise in cyclosporiasis, reporting 145 cases of the parasitic illness acquired within the United States between May 1 and June 16, 2026.
The Centers for Disease Control and Prevention (CDC) confirmed the infections span 17 states. While local and federal authorities are investigating several small clusters of cases, officials emphasize there is currently no evidence of a single, nationwide outbreak linking all the illnesses. Instead, the current figures reflect a broader surveillance count of cases across the country.
Cyclosporiasis is an intestinal illness caused by the microscopic parasite Cyclospora. It is a nationally notifiable disease, and health agencies monitor infections closely each year between May 1 and August 31, when case counts typically surge. The parasite is usually contracted by consuming food or water contaminated with fecal matter.
Of the 145 domestic cases reported so far this season, patients range in age from 5 to 86, with a median age of 42. Women account for 61% of the illnesses. While 20 people have been hospitalized due to the infection, no deaths have been reported. The median date for the onset of symptoms was May 13.
Public health officials note that the true number of infections is likely higher than the official tally, as many people recover from the illness without seeking medical care or being tested.
In addition to the domestic cases, the CDC reported 45 cases tied to international travel. These individuals became sick after consuming contaminated food or water outside the United States before returning home. Three of those travelers required hospitalization.
The CDC, the Food and Drug Administration (FDA), and state health departments are actively conducting traceback investigations on known clusters to identify potential food sources. In the meantime, healthcare providers are encouraged to test patients showing symptoms of the infection and report confirmed cases to local health departments.
