What to Know as Cyclosporiasis Cases Increase Across New York, US

ELLENVILLE, N.Y. — As health officials investigate a multistate outbreak of the intestinal parasite Cyclospora, an emergency physician at Ellenville Regional Hospital is urging local residents to recognize the symptoms of the illness and practice safe food handling during peak produce season.

Dr. David Williams said the parasite, which causes the illness cyclosporiasis, is more severe than a typical stomach virus and can lead to prolonged diarrhea, dehydration and electrolyte imbalances, particularly in children, older adults and people with weakened immune systems.

“It’s much different than your 24-hour bug,” Williams said during an interview with Radio Catskill. “It causes a lot of diarrhea.”

The New York State Department of Health recently issued a health advisory reporting an increase in cyclosporiasis cases statewide, Williams said. He noted there have been approximately 290 cases reported outside New York City and about 381 cases in the city. He said he was aware of only one or two reported cases in Ulster County and that Ellenville Regional Hospital had not yet treated a patient with the illness. The Michigan Department of Health recorded the highest number of cyclosporiasis cases on Friday at over 1,500. Other heavily impacted states include Ohio, Illinois, and Florida.

Cyclosporiasis is caused by a microscopic parasite that infects the small intestine. Unlike common foodborne illnesses, symptoms typically do not appear until about a week after exposure, making it difficult for people to identify the contaminated food that caused the infection.

Williams said symptoms include frequent watery diarrhea, abdominal bloating, cramping, nausea and fatigue.

“It takes seven to 10 days to develop,” he said, explaining that the parasite damages the intestine’s ability to absorb nutrients before symptoms begin.

The parasite is commonly linked to fresh produce, including lettuce, cilantro, basil and raspberries, although investigators have not yet identified the source of the current outbreak.

Williams encouraged people to continue eating fresh fruits and vegetables but stressed the importance of washing produce thoroughly and purchasing it from trusted sources.

“I think it’s more about safe food handling,” he said. “Wash your vegetables and clean your produce and make sure they come from a good source.”

He noted that leafy greens and raspberries can be especially difficult to clean because microscopic crevices on their surfaces can allow parasite cysts to remain attached even after rinsing.

Williams said anyone experiencing persistent watery diarrhea, especially if accompanied by signs of dehydration, should seek medical attention.

“If you’re still having diarrhea, you’ve got to come into the emergency department,” he said.

He added that stool testing can identify the parasite but cautioned that standard stool parasite tests may not automatically include Cyclospora unless clinicians specifically request it. Ellenville Regional Hospital has added testing for the parasite to its stool testing panel, he said.

Williams also addressed another health concern emerging this summer: alpha-gal syndrome, a potentially serious allergy to red meat that can develop after a bite from the lone star tick.

Although the tick is still relatively uncommon in the region, Williams said it is becoming more prevalent.

“It’s another reason not to eat red meat,” he said, while emphasizing that preventing tick bites remains the best defense.

For cyclosporiasis, his advice was straightforward.

“Wash your hands, wash your vegetables and clean your produce,” Williams said. “We don’t know what’s causing this yet, but it’s important to take those precautions.”

Image: Laboratory testing is used to confirm Cyclospora infections, as the parasite is more difficult to identify than many common foodborne pathogens.(CDC)