Cyclospora cases rise across 17 states as summer progresses

The U.S. Centers for Disease Control and Prevention has recorded 145 cases of cyclosporiasis acquired domestically as of June 16, and health officials say the parasite is spreading in 17 states this summer. Michigan's health department reported a sharp increase, with 572 cases reported in July, up from 170 at the end of June.

Cyclospora, a foodborne parasite that causes severe watery diarrhea, is most often linked to fresh produce with uneven surfaces such as parsley, cilantro, snow peas, mesclun lettuce, spinach, salad mixes and berries. Dr. Steven Goldberg, chief medical officer at HealthTrackRx, explained that the irregular texture of these items allows the organism to hide in crevices, making thorough cleaning difficult.

The parasite does not spread directly from person to person; infection occurs when contaminated food is handled or prepared by someone with diarrhea. "The way this spreads is from a person having diarrhea and some of that material getting into either food prep or food service," Goldberg said.

Cases typically rise from May through August. Since 2013, the Food and Drug Administration has documented 21 cyclospora-related outbreaks, most involving fresh herbs and leafy vegetables. Health experts advise consumers to wash produce with a strong flow of water and manually scrub surfaces, avoiding bleach or other cleaning agents. "If you’re going to a farmer’s market or other area and you purchase food, that food has to have a prep process other than just soaking in water. It needs to be washed with a forceful water flow and manually cleaned," Goldberg added.

Symptoms include explosive watery diarrhea, cramping, nausea, fatigue and, in some cases, vomiting or low-grade fever. While most infections resolve within days, severe or persistent cases may require antibiotics. The CDC recommends thorough hand washing, scrubbing firm fruits and vegetables with a clean brush, cutting away damaged areas and refrigerating cut produce within two hours.

There is currently no evidence of a single multistate outbreak linking all reported cases, and officials note an overall upward trend in cyclospora infections linked to domestically grown produce. "We’re seeing now this year an acceleration of food-related illness in the United States. We don’t have a single explanation for it. It’s not clear if it is coming from farms or if there are other sources involved," Goldberg said.