HEALTH ADVISORY: Test patients with symptoms consistent with Cyclospora infection

Summary

State health departments, the Centers for Disease Control and Prevention, and the Food and Drug Administration are currently preparing for the annual Cyclospora outbreak season that runs from May to August. In 2023, Texas had more than 800 reported cases of cyclosporiasis with most cases occurring between May and August. The Texas Department of State Health Services (DSHS) is advising healthcare providers to test patients for the parasite Cyclospora if they have a diarrheal illness lasting more than a few days or diarrhea accompanied by severe loss of appetite or fatigue and to report cases to their local health department.

Background

Cyclosporiasis is an intestinal illness caused by the Cyclospora parasite.

People can become infected with Cyclospora by consuming food or water contaminated with the parasite. Persons of all ages are at risk of infection. Symptoms of cyclosporiasis usually begin 2 to 14 days after ingestion of Cyclospora eggs, or oocysts, in contaminated food or water. Watery diarrhea can persist for several weeks to a month or more, and affected patients may experience a return of symptoms after improvement. Additional symptoms may include anorexia (loss of appetite), fatigue, weight loss, abdominal cramps, bloating, increased gas, nausea, vomiting, and low-grade fever.

Previous outbreaks have been associated with the consumption of fresh produce, including fresh cilantro, broccoli, Italian parsley, pre-packaged salad mix, raspberries, basil, snow peas, and mesclun lettuce. Avoiding food or water contaminated with feces is the best way to prevent cyclosporiasis.

Recommendations for Healthcare Providers

Clinicians should order testing for patients who have symptoms consistent with cyclosporiasis. They can submit stool specimens for “ova and parasite” testing with a modified acid-fast stain, modified safranin (“hot”) stain, and/or UV autofluorescence screen with specific orders for Cyclospora identification. Due to the intermittent shedding of the parasite, a single negative stool specimen does not exclude the diagnosis; three specimens taken at least 24 hours apart are optimal. Cyclospora may also be detected by molecular methods such as polymerase chain reaction (PCR).

Rapid reporting to public health is essential to preventing additional cases of cyclosporiasis. Healthcare providers and laboratories are required to report confirmed cyclosporiasis cases to their respective local health departments within one week. DSHS asks that healthcare providers remain vigilant in surveillance and testing. Clinical specimens are encouraged to be submitted to the DSHS laboratory for confirmation.

Recommendations for the public

DSHS recommends washing hands with soap and water before and after handling or preparing fruits and vegetables and thoroughly washing/scrubbing all fresh produce, cutting boards, dishes, utensils, and countertops. Consumers, retailers, and restaurants should be aware that washing may not eliminate all risk of transmission since Cyclospora can be difficult to remove from produce. Routine chemical disinfection or sanitizing methods are unlikely to kill the parasite. Cyclospora does not appear to spread through direct person-to-person contact.