A microscopic parasite called Cyclospora is spreading across 17 states. 145 people are sick. Health care workers need to know the warning signs, how to diagnose it, and what to do. Read why this outbreak matters and how to respond.
As of mid-June 2026,
What IPC Professionals Should Know
Cyclosporiasis is a gastrointestinal disease that spreads through contaminated food or water, not person-to-person. The parasite causes diarrhea, cramps, nausea, and fatigue, with an incubation period of approximately 7 to 10 days after exposure.
Clinical Presentation and Diagnosis
Health care workers should maintain a high index of suspicion for cyclosporiasis in patients presenting with:
Diagnosis requires stool microscopy to identify Cyclospora oocysts. Multiple stool samples may be necessary, as parasite shedding can be intermittent. Some laboratories use special staining techniques to enhance detection.
Treatment and Management
For patients with sulfa allergies, alternative antibiotic regimens should be considered in consultation with infectious disease specialists.
Supportive care is essential, including maintaining adequate hydration, monitoring electrolyte balance, and managing symptoms as needed. Most patients recover fully with appropriate treatment, though immunocompromised individuals may experience prolonged illness.
Current Outbreak Status
All 145 domestic cases acquired between May 1 and June 6, 2026, involved no international travel in the preceding 2 weeks, indicating a domestic food or water source. The CDC and FDA are actively investigating multiple multistate clusters, though no confirmed food source has been identified yet. An additional 45 travel-related cases were reported among individuals who became ill after consuming contaminated food or water outside the US.
Resources and Reporting
CDC Cyclosporiasis Information:
World Health Organization Resources on Foodborne Parasitic Infections:
For Ohio Health Care Workers:
Contact the Ohio Department of Health at 1-888-246-5005 or visit odh.ohio.gov for state-specific surveillance data and reporting requirements.
Infection Prevention Recommendations
While person-to-person transmission is rare, standard precautions should be maintained for hospitalized patients with acute diarrhea. Emphasize hand hygiene, especially after patient contact and before food handling. Educate patients about food and water safety to prevent secondary spread.
IPC professionals should collaborate with epidemiology and infectious disease teams to identify potential sources of exposure and support outbreak investigations. Early recognition and reporting of cyclosporiasis cases remain critical tools in controlling this emerging seasonal threat.
