LINCOLN, Neb. (AP) — Iowa and Nebraska health officials say a prepackaged salad mix is the source of a cyclospora outbreak that sickened more than 178 people in both states. Public health officials from both states announced their findings on Tuesday. Outbreaks of the same illness have been reported elsewhere in the U.S., but it’s not clear if prepackaged salad mix is also linked to those. Cyclospora is a rare parasite that causes a lengthy gastrointestinal illness.

Nebraska officials say the salad mix came through national distribution channels. It included iceberg and romaine lettuce, along with red cabbage and carrots. Local health departments are working with the U.S. Food and Drug Administration to identify exactly where the contamination originated in the food production chain and where the product was distributed.