US Faces Largest Cyclospora Season Ever

The United States is currently experiencing its largest cyclospora season on record, with over 4,173 laboratory-confirmed cases reported since May 1st, 2026. Thousands more illnesses are under review by health officials.

Federal investigators are examining multiple outbreaks and have identified one multistate outbreak linked to iceberg lettuce sourced from central Mexico. A recall of certain iceberg lettuce products was issued on July 17th as part of this ongoing investigation.

Cyclosporiasis, an intestinal illness caused by the microscopic parasite Cyclospora cayetanensis, is characterized by prolonged watery diarrhea, stomach cramps, fatigue, and loss of appetite. While usually rising in spring and summer, this year's surge is significantly larger than normal.

Doctors stress that while most individuals recover with proper treatment, dehydration is the most significant immediate threat. A specific antibiotic, trimethoprim-sulfamethoxazole, is the standard treatment, alongside crucial hydration. Early diagnosis, which requires a specific test ordered by a clinician, is vital.

Experts emphasize that death from cyclospora is exceedingly rare, with no deaths reported in the current outbreak. However, individuals with weakened immune systems may face a greater risk of prolonged or severe illness. The primary danger lies in delayed diagnosis and the resulting complications from prolonged fluid loss.