Seven ill people were reported from California (1), Illinois (1), Maryland (1), Ohio (2), Pennsylvania (1), and Washington (1) since the last update, said the US Centers for Disease Control and Prevention (CDC).
Of the three most recent illnesses in November, only one, whose illness started on November 10, reported eating at Chipotle Mexican Grill in the week before illness began, said the agency.
A total of 20 people have been hospitalized but there have been no reports of hemolytic uremic syndrome (HUS) and no deaths.
Specific food not identified
Current evidence suggests that a common meal item or ingredient served at Chipotle Mexican Grill restaurants in several states is a likely outbreak source.
A total of 47 (90%) of 52 ill people interviewed reported eating at a Chipotle Mexican Grill restaurant in the week before their illness started but a specific food has not been identified.
The majority of illnesses were reported from Washington and Oregon during October.
Illnesses started on dates ranging from October 19 to November 13, ill people range in age from one year to 94 and 59% are female.
Whole genome sequencing on STEC O26 isolates from 21 ill people from California (2), Minnesota (2), New York (1), and Washington (16) show all isolates were highly related genetically to one another.
This provides additional evidence that illnesses outside the Pacific Northwest, could be related to those in Washington, said the Food and Drug Administration (FDA).
Chipotle Mexican Grill has reopened its restaurants in Washington and Oregon that had been closed in response to the investigation.
Work with IEH Laboratories
Chipotle has retained IEH Laboratories to help it identify opportunities to enhance food safety practices throughout its operations.
The firm said thousands of food sample tests from restaurants have shown no E. coli.
No ingredients that are likely to have been connected remain in Chipotle’s restaurants or in its supply system and no employees have been identified as having E. coli since this incident began.
Mansour Samadpour, CEO of IEH Laboratories and Consulting Group, said he was asked to design a more robust food safety program to ensure safety and quality of meals served at Chipotle.
“I am happy to report that our proposed program was adopted in its entirety, without any modification. While it is never possible to completely eliminate all risk, this program eliminates or mitigates risk to a level near zero, and will establish Chipotle as the industry leader in this area."
The enhanced program includes high-resolution testing of all fresh produce in which a series of DNA-based tests will ensure quality and safety of ingredients before they are shipped to restaurants and end-of-shelf-life testing where ingredient samples will be tested to ensure quality specifications are maintained throughout shelf life of an ingredient.