PA Parasite Outbreak: 28 Cases Now Confirmed Statewide

Confirmed case numbers of cyclosporiasis are now up to 28 in Pennsylvania, according to data from the state Department of Health, as health officials work to address the outbreak.

The parasitic infection, which causes diarrhea, has now grown to more than a thousand cases nationwide. Cases are concentrated in Michigan, but have been reported in 28 different states, according to the CDC.

Related: These Fruits, Vegetables May Be Linked To PA's Growing Parasite Outbreak

The 28 number in Pennsylvania almost exceeds the 40 that were recorded for the entire year of 2025. It is not yet known exactly where in the state these cases are concentrated, though NBC10 reported that at least 10 of the cases are in the densely populated southeastern part of the state.

Cyclosporiasis is an intestinal illness caused by the Cyclospora parasite, which is commonly found in developing countries and spread by food or water contaminated with feces. It infects the small intestine and usually causes frequent, watery, explosive diarrhea.

Many cases have been connected to certain fruits and vegetables, including bagged salad mixes and kits, fresh cilantro, fresh basil, raspberries, snow peas, and green onions.

Symptoms usually begin about a week after someone consumes contaminated food or water, though they can appear as soon as two days or more than two weeks later. Watery diarrhea is the most common symptom.

Cyclosporiasis is not usually life-threatening, but dehydration from frequent bouts of diarrhea can cause severe illness, particularly among younger or older people and those who have weakened immune systems.

There isn't much data on Cyclosporiasis cases since outbreaks have eclipsed 1,000 cases only a handful of times in the last 20 years. The last outbreak happened in 2019 when Mexican basil sickened more than 2,400 people across the U.S. and Canada.

University of Minnesota foodborne illness researcher Melanie Firestone told the Associated Press most tests to detect food poisoning are not geared to check for Cyclospora.

It can also be challenging to trace food contaminated with Cyclospora because food distributors may ship the food to both grocery stores and restaurants.

With reporting from Patch correspondent Dylan Siwicki