(CNN) — The outbreak of E. coli linked to Chipotle Mexican restaurants has now caused individuals to become ill in nine states since October, the Centers for Disease Control and Prevention said Friday.
Illinois, Maryland and Pennsylvania now join California, Minnesota, New York, Ohio, Oregon, and Washington in reporting cases linked to the outbreak.
The agency also reported seven additional cases of illness that occurred in October and November. The most recent sick individual began feeling ill on November 13.
In all, 52 people have become ill, most of them reported eating food from Chipotle within the week before their symptoms began. Twenty of those individuals have been hospitalized.
Symptoms, which include diarrhea and abdominal pain, usually begin two to eight days after a person has been exposed to the bacteria and resolve within a week. Some cases are severe and patients can develop hemolytic uremic syndrome, or HUS, which is a type of kidney failure. There have been no cases of HUS or deaths from this outbreak.
The restaurant chain said it is continuing to work with federal, state and local health officials to investigate the outbreak. They have not yet identified a single food source or menu item as the culprit.
The outbreak was initially limited to Chipotle locations in Washington and Oregon, where locations were closed as a precaution during the initial investigation. They reopened last month.
In a statement issued Friday, Chipotle said they have “taken aggressive actions to implement industry-leading food safety and food handling practices in all of its restaurants and throughout its supply chain.” This is beyond food safety practices previously in place, the statement said. Improvements include enhanced testing and training, among other measures.
Mansour Samadpour, CEO of IEH Laboratories and Consulting Group, which was hired by Chipotle as an outside food safety consultant, said in a press release, “this program eliminates or mitigates risk to a level near zero and will establish Chipotle as the industry leader in this area.”
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