The U.S. Centers for Disease Control and Prevention (CDC) announced Tuesday that, as of Nov. 23, there were 19 people from seven states sickened by the outbreak strain of Shiga toxin-producing E. coli O157:H7 linked to consumption of Costco chicken salad made with rotisserie chicken. Five people have been hospitalized and two developed hemolytic uremic syndrome (HUS), a serious kidney problem associated with Costco chicken salad labelE. coli infections. No deaths have been reported, according to CDC. 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 this outbreak, the federal agency stated. The majority of illnesses have been reported from western 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). In Montana, which so far has reported the highest number of cases, two of those sickened were hospitalized, according to the Montana Department of Health and Human Services. The six people sickened in Montana were reported from Gallatin, Lewis & Clark and Yellowstone counties, the department noted in a release posted Tuesday, Nov. 24, adding that Costco had pulled the chicken salad product from shelves in that state.

  • The epidemiologic evidence available at this time suggests that rotisserie chicken salad made and sold in Costco Wholesale stores in several states is a likely source of this outbreak, CDC stated.
    • 14 (88 percent) of 16 people purchased or ate rotisserie chicken salad from Costco in the week before illness started.
    • The ongoing investigation has not identified what specific ingredient in the chicken salad is linked to illness.
  • On Nov. 20, 2015, Costco reported to public health officials that the company had removed all remaining rotisserie chicken salad from all stores in the U.S. and stopped further production of the product until further notice.
  • Consumers who purchased rotisserie chicken salad from any Costco store in the U.S. on or before Nov. 20, 2015, should not eat it and should throw it away.
    • Even if some of the rotisserie chicken salad has been eaten and no one has gotten sick, throw the rest of the product away.
    • This product has a typical shelf life of three days and is labeled “Chicken Salad made with Rotisserie Chicken” with item number 37719 on the label.
    • A picture of the product label is available on the Advice to Consumers page.
  • This investigation is ongoing. CDC and state and local public health partners are continuing laboratory surveillance through PulseNet to identify additional ill persons and to interview them.

Public health investigators are using the PulseNet system to identify illnesses that may be part of this outbreak. PulseNet, the national subtyping network of public health and food regulatory agency laboratories, is coordinated by CDC. DNA “fingerprinting” is performed on E. coli bacteria isolated from ill people by using a technique called pulsed-field gel electrophoresis, or PFGE. PulseNet manages a national database of these DNA fingerprints to identify possible outbreaks. Among people for whom information is available, illnesses started on dates ranging from Oct. 6, 2015, to Nov. 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. This outbreak can be illustrated with a chart showing the number of people who became ill each day. This chart is called an epidemic curve or epi curve. Illnesses that occurred after Nov. 10, 2015, might not be reported yet due to the time it takes between when a person becomes ill and when the illness is reported. This takes an average of 2 to 3 weeks. See the Timeline for Reporting Cases of E. coli Infection for more details. CDC stated that the agency will provide more updates when more information is available.

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