The source of the current US outbreak is unknown, but in the past, cyclosporiasis has been linked to raspberries, basil, snow peas, green onions, and lettuce.

As state health officials scramble to find the source of the foodborne parasite, the CDC said Friday it’s unclear whether the outbreaks across the country are connected.

Cyclosporiasis has sickened some 2,000 Americans so far this year.

A widespread parasite outbreak in the US causes diarrhea, affecting 31 states; learn about symptoms, transmission, and prevention.