Test Patients with Symptoms Consistent of Cyclospora Infection

West Virginia Health Advisory Number WV236 | July 9, 2026

Summary

The West Virginia Bureau for Public Health (WVBPH) is investigating an increase in cyclosporiasis cases occurring across the state. As of July 9, 2026, 47 cases have been reported in West Virginia since June 17. On average West Virginia receives nine reports of Cyclospora annually. Illnesses are currently concentrated in counties along the state’s western border. At this time, epidemiologic investigations have not identified a common food item, produce supplier, grower, or distributor associated with these illnesses.

Nationally, as of July 9, 2026, the Centers for Disease Control and Prevention (CDC) has identified 729 confirmed cases in 30 states. Patients became ill after consuming food in the United States and did not report international travel during the 14 days before illness onset. Currently, there is no evidence of a single multistate outbreak linking all reported cases. Healthcare providers should maintain a heightened awareness for cyclosporiasis in patients presenting with prolonged or relapsing diarrheal illness, particularly those without recent international travel.

Background

Cyclosporiasis is an intestinal illness caused by the parasite Cyclospora cayetanensis. Infection occurs through the ingestion of food or water contaminated with sporulated Cyclospora oocysts. Because oocysts require days to weeks in the environment to become infectious, direct person-to-person transmission is considered unlikely.

Symptoms typically develop 2 to 14 days after exposure and commonly include:

  • Prolonged watery diarrhea
  • Loss of appetite
  • Fatigue
  • Weight loss
  • Abdominal cramping
  • Bloating and increased gas
  • Nausea and vomiting
  • Low-grade fever

Illness may last for several weeks or longer, and symptoms frequently relapse after temporary improvement if left untreated. Historically, outbreaks in the United States have been associated with imported and domestically grown fresh produce, including cilantro, basil, broccoli, Italian parsley, pre-packaged salad mixes, raspberries, snow peas, and mesclun lettuce.

Recommendations for Healthcare Providers

Considering the increase in Cyclospora cases, BPH is recommending healthcare providers:

  1. Consider cyclosporiasis in patients presenting with prolonged or relapsing watery diarrhea, especially during the summer months.
  2. Order appropriate diagnostic testing. Routine stool ova and parasite examinations and many multiplex gastrointestinal PCR panels do not routinely detect Cyclospora. If clinically indicated, providers should specifically request testing for Cyclospora cayetanensis.
  3. Initiate appropriate treatment. The treatment of choice for cyclosporiasis is trimethoprim-sulfamethoxazole (TMP-SMX), unless contraindicated.
  4. Report suspected or confirmed cases promptly to the local health department. Cyclosporiasis is a reportable condition in West Virginia and should be reported within 72 hours of diagnosis or suspicion.
  5. Submit clinical specimens to the West Virginia Office of Laboratory Services (OLS) for confirmatory testing and molecular characterization at CDC whenever possible. Complete the Microbiology Laboratory Specimen Submission Form using Outbreak Number 315.
  6. Prioritize specimen collection from individuals symptomatic for less than 72 hours; place specimens in Cary Blair medium immediately.
  7. View Specimen Collection Instructions for additional collection details.

Early recognition and reporting of infectious diseases are critical to protecting public health and supporting timely investigation and response activities. Additional resources can be found on our website at: https://oeps.wv.gov/. For questions or to report a public health concern, please contact the Office of Epidemiology and Prevention Services Epidemiologist-On-Call at (304) 558-5358.

This message was directly distributed by the West Virginia Bureau for Public Health to local health departments and professional associations. Receiving entities are responsible for further disseminating the information as appropriate to the target audience.

To download the full advisory, click here.