What is cyclosporiasis, the parasitic illness causing ‘explosive’ diarrhea?

Key Points:

• Cyclosporiasis is a gastrointestinal illness caused by the parasite Cyclospora, which spreads through raw produce and contaminated water, with symptoms including watery diarrhea, cramps, nausea, and fatigue, lasting from days to over a month.
• In the US, cyclosporiasis is seasonal, occurring mainly between May and August, with past outbreaks linked to contaminated fruits, vegetables, and herbs such as basil, cilantro, berries, and spinach.
• Major outbreaks have involved contaminated produce like Guatemalan raspberries in 1996 and Mexican basil in 2019, with cases sometimes exceeding 1,000 individuals; a 2022 Florida outbreak was tied to lettuce in packaged salad kits.
• Prevention focuses on avoiding contaminated food and water, thoroughly washing fresh produce, especially those with crevices like berries and leafy greens, and cooking vegetables when possible to kill the parasite.
• Health officials advise buying whole heads of lettuce instead of pre-washed, bagged varieties and removing outer leaves before washing to reduce infection risk, while treatment typically involves antibiotics, especially for those with weakened immune systems.