If you’ve been hesitant to reach for the raspberries or bagged greens at your local supermarket after hearing of cases of “explosive diarrhea,” you may be wise to follow that instinct. Several states across the country are, in fact, seeing outbreaks of Cyclospora, a parasite that can contaminate fresh produce and cause highly unpleasant stomach symptoms.

What Is Cyclospora?

Cyclospora is a single-celled parasite that is endemic in many tropical and subtropical areas of the world, said Charles Bailey, MD, the medical director for infection prevention at Providence St. Joseph Hospital and Providence Mission Hospital.

People become infected after drinking water or eating fresh produce contaminated with the parasite.

Federal and state investigators are also examining lettuce as a possible source of the current outbreak, but no food has been confirmed as the source. Previous outbreaks have been linked to raspberries, basil, cilantro, mixed salad greens, snow peas, and bagged salads.

Cyclosporiasis cases in the United States typically increase during the spring and summer, as warmer months often bring increased availability and consumption of fresh, uncooked fruits and vegetables, as well as more international travel to regions where Cyclospora is endemic.

According to the latest data from the Centers for Disease Control and Prevention (CDC), the agency has received reports of 1,645 confirmed domestic cases of Cyclosporiasis since May 1. Multiple states have reported an increase in cases compared to the same period in 2025.

“While 2026 appears to be on track to be one of the highest annual Cyclospora case totals, several previous years also had cases in excess of a thousand: 2014, 2019, and 2021,” Bailey said. “All U.S. outbreaks have occurred between May and September.”

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Symptoms You Should Look Out For

Symptoms of a Cyclospora infection can resemble those of other stomach illnesses, and it can only be distinguished from bacterial, viral, or other non-infectious causes through a medical test, Bailey explained.

“Diarrhea in Cyclospora tends to be watery, non-bloody, high-volume, and descriptions of ‘explosive’ episodes are not uncommon,” he said.

While diarrhea is the most common symptom, other symptoms include loss of appetite, fatigue, weight loss, abdominal bloating and cramping, nausea, fever, muscle aches, and vomiting, according to Nikhil Bhayani, MD, an infectious disease specialist and assistant professor at the Anne Burnett Marion School of Medicine at TCU.

“Symptoms characteristically wax and wane and can persist for days to weeks or longer if untreated,” Bhayani said.

For most people, treatment for Cyclospora involves fluid and electrolyte replacement, along with medications to help reduce symptoms, Bailey said. If Cyclospora is confirmed by testing or strongly suspected, he said, antibiotic therapy can be given for persistent or severe symptoms and in more vulnerable people.

How to Protect Yourself From Cyclospora

Cyclospora is resistant to routine chemical disinfectants, including the chlorine levels commonly used to treat water. Washing fresh fruits and vegetables under running water is still recommended, although it does not eliminate the risk of infection.

“This reduces but does not eliminate risk, as standard washing and sanitizing methods are unlikely to kill Cyclospora oocysts,” Bhayani said.

Bhayani also recommends washing your hands before preparing or eating food and after using the bathroom, and paying attention to any produce linked to ongoing U.S. outbreaks.

The most reliable way to kill the parasite is to cook your food to a temperature of 158°F or higher.

“Cooking well-cleaned vegetables will significantly reduce, if not eliminate, any risk of Cyclospora infection,” Bailey added. “And avoiding consumption of uncooked fruits and vegetables would also essentially eliminate your risk.”