Twenty-eight Westchester County residents have gotten sick from the cyclospora parasite so far this year — a number County Executive Ken Jenkins says is nothing to panic about, even as the same illness explodes into one of the largest outbreaks the country has seen in years.

Westchester's case count is only slightly above last year's pace of 23 cases over the same stretch. "That's about average," Jenkins said. Nine of the county's recent cases don't appear connected to each other, and the county health department is monitoring the situation.

Nationally, it's a different story. As of Monday, the CDC had confirmed 1,645 U.S. cases across 34 states, with 141 hospitalizations, and is investigating more than 5,100 additional suspected cases. New York State has confirmed nearly 400 cases since May, with New York City alone reporting over 400 on its own. Michigan is the hardest hit, with more than 3,300 confirmed cases.

Federal investigators are looking into whether lettuce served at Michigan Taco Bell locations might be linked, but nothing's confirmed. Gwen Biggerstaff of the CDC said the agency expects cases to keep climbing through August, the typical end of cyclospora season.

Cyclospora cayetanensis infects the intestines and spreads through contaminated produce — past outbreaks have been traced to raspberries, basil, cilantro, snow peas, and bagged salads. Symptoms usually start about a week after exposure: watery diarrhea, cramps, bloating, nausea, and fatigue that can drag on for weeks or return after seeming to clear up. It takes a specialized stool test to diagnose — a standard panel won't catch it.

Wash your hands before and after handling raw produce, rinse fruits and vegetables thoroughly under running water, scrub firm produce with a clean brush, and refrigerate anything cut or peeled within two hours.

Anyone with GI symptoms after eating fresh produce should contact their healthcare provider. The recommended treatment is the antibiotic trimethoprim-sulfamethoxazole, sold as Bactrim.