Wendy’s clients fall ill, Centers for Disease Control and Prevention (CDC) investigates outbreaks of E. coli in four states

An overview of the US Centers for Disease Control and Prevention (CDC) headquarters in Atlanta, Georgia, September 30, 2014. REUTERS/Tami Chappelle/

(Reuters) – The U.S. Centers for Disease Control and Prevention said it is investigating the spread of Escherichia coli bacteria in four states from an unknown food source, and many of those infected reportedly ate sandwiches at Wendy’s Co. (We do not).

Of the 37 patients, 22 were said to have eaten Wendy’s sandwiches with romaine lettuce in Michigan, Ohio, Indiana and Pennsylvania in the week prior to their illness.

However, investigators have not yet confirmed whether romaine lettuce was the cause and also whether the vegetables used in Wendy’s sandwiches were served or sold at other companies.

The burger chain said it was taking precautions to remove the lettuce sandwich from its restaurants in the area. Approximately 1,100 of the 5,940 American Wendy’s restaurants are located in the four states.

The illness began between July 26 and August 8 and a total of 10 people were hospitalized, three of whom in Michigan developed some form of kidney failure.

Escherichia coli bacteria live naturally in the intestines of healthy people and animals. Although many strains are harmless, certain types can cause severe abdominal cramps, bloody diarrhea and vomiting.

The CDC said the exact number of people affected is likely to be higher and the outbreak may not be limited to the four states.

Additional reporting by Praveen Paramasivam in Bengaluru; Editing by Aaron Coeur

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