CDC investigates Cyclospora cases as parasite sickens more than 1,200 people

CDC is tracking 145 U.S.-acquired Cyclospora cases reported from May 1 through June 16, with illnesses in 17 states, 20 hospitalizations and no deaths so far, but investigators have not linked them to a single multistate outbreak. Several clusters are still under review as cyclosporiasis typically peaks from May through August.

The most likely source is fresh produce contaminated somewhere along the farm-to-table chain. Cyclospora outbreaks have been associated with fresh fruits and vegetables, and U.S. outbreaks have been tied to imported raspberries, basil, snow peas, mesclun lettuce and cilantro. Infected people can shed the parasite in stool, so weak hygiene can contaminate food, water and the environment.

CDC says cyclosporiasis cases are often scattered across states, and interviews commonly happen 4 to 6 weeks after illness starts, long after a meal detail has faded. A 2013 investigation showed the scale of the challenge: CDC and FDA identified 631 reported cases across 25 states and New York City, and concluded more than one outbreak was happening at the same time.

CDC typically coordinates 17 to 36 multistate foodborne-illness investigations each week, while FDA created a Cyclospora Task Force in 2019 to work on prevention, response and research. Households can reduce risk now by washing hands before and after handling raw fruits and vegetables, rinsing produce under running water, scrubbing firm items like cucumbers and melons, and refrigerating cut or peeled produce within two hours. Anyone with prolonged diarrhea should ask a clinician to specifically test for Cyclospora, which is treated with trimethoprim-sulfamethoxazole.