Romaine on Wendy's sandwiches likely culprit in E. Coli outbreak in the Midwest, CDC says

• Romaine on Wendy's sandwiches is likely to be the cause of an E. coli outbreak in the Midwest.
• The CDC reported that 37 people were sickened, and they are currently investigating.

An E. coli outbreak in the Midwest has sickened an estimated 37 people, many of which ate at a Wendy's restaurant before their symptoms emerged, The Centers for Disease Control and Prevention said Friday.

According to the CDC, while "a specific food has not yet been confirmed as the source," several of the E. coli patients reported eating sandwiches containing romaine lettuce at Wendy's locations in Michigan, Ohio, and Pennsylvania.

Investigators are working to definitively determine the source of the outbreak, and Wendy's is fully complying with the inspection, the CDC said in a statement.

Wendy's did not immediately respond to Insider's request to comment, but the CDC reported the restaurant is removing romaine from its Midwestern locations.

Based on its findings thus far, the CDC said there is no evidence that romaine lettuce purchased from grocery stores or other restaurants has contributed to the outbreak.

Fresh produce is the source of nearly half of foodborne illness outbreaks in the US, with leafy greens like romaine among the most susceptible to carrying the bacteria thanks to the folds in their leaves. In most cases, the produce picks up the bacteria by coming into contact with irrigation systems that have been contaminated with livestock feces.

E. coli can cause bloody diarrhea, fever, stomach cramps, vomiting, and in extreme cases, kidney failure. If you are exhibiting any of these symptoms, the CDC recommends that you write down what you ate the week before and contact your local or state health department.