CDC, the U.S. Food and Drug Administration, the U.S. Department of Agriculture Food Safety and Inspection Service, and public health officials in several states are investigating an outbreak of Shiga toxin-producing Escherichia coli O157:H7 (STEC O157:H7) infections.
A total of 19 people infected with the outbreak strain of Shiga toxin-producing STEC O157:H7 have been reported from 7 states. The majority of illnesses have been reported from states in the western United States. The number of ill people reported from each state is as follows: California (1), Colorado (4), Missouri (1), Montana (6), Utah (5), Virginia (1), and Washington (1).
Among people for whom information is available, illnesses started on dates ranging from October 6, 2015 to November 3, 2015. Ill people range in age from 5 years to 84, with a median age of 18. Fifty-seven percent of ill people are female. Five (29%) people reported being hospitalized, and two people developed hemolytic uremic syndrome (HUS), a type of kidney failure. No deaths have been reported..
The epidemiologic evidence available to investigators at this time suggests that rotisserie chicken salad made and sold in Costco stores is a likely source of this outbreak. The ongoing investigation has not identified what specific ingredient in the chicken salad is linked to illness.
State and local public health officials are interviewing ill people to obtain information about foods they might have eaten and other exposures in the week before their illness started. Fourteen (88%) of 16 people purchased or ate rotisserie chicken salad from Costco.
On November 20, 2015, Costco reported to public health officials that the company had removed all remaining rotisserie chicken salad from all stores in the United States and stopped further production of the product until further notice.