(USATODAY) — DES MOINES, Iowa — You might want to finish your breakfast before reading this story.

Public-health investigators said Friday that fresh vegetables probably are the source of a rare parasite causing severe diarrhea in dozens of Iowans.

They weren’t ready to cite a specific culprit, but they said the cyclospora contamination probably came from a single type of vegetable shipped from a single farm, likely outside of Iowa.

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