Multistate Outbreak of Multidrug-Resistant Salmonella Heidelberg Infections Linked to Foster Farms Brand Chicken— United States, 2013

Gieraltowski, Laura

Tuesday, June 24, 2014: 2:36 PM

102, Nashville Convention Center

Jolene Nakao , Centers for Disease Control and Prevention, Atlanta, GA

Jeffrey Higa , California Department of Public Health, Gardena, CA

Vi Peralta , California Department of Public Health, Richmond, CA

Hilary Rosen , California Department of Public Health, Gardena, CA

Tanya E. Libby , California Emerging Infections Program, Oakland, CA

Nicola Marsden-Haug , Washington Department of Health, Shoreline, WA

Akiko Kimura , California Department of Public Health, Gardena, CA

Colin Schwensohn , Centers for Disease Control and Prevention, Atlanta, GA

Jeshua Pringle , Centers for Disease Control and Prevention, Atlanta, GA

Alice Green , U.S. Department of Agriculture, Minneapolis, MN

Bonnie Kissler , U.S. Department of Agriculture, Atlanta, GA

Kis Robertson , U.S. Department of Agriculture, Washington, DC

Julian Grass , Centers for Disease Control and Prevention, Atlanta, GA

Amelia Bicknese , Centers for Disease Control and Prevention, Atlanta, GA

Beth Tolar , Centers for Disease Control and Prevention, Atlanta, GA

Stephanie Defibaugh-Chávez , Usda-Fsis, Washington, DC

Matthew Wise , Centers for Disease Control and Prevention, Atlanta, GA

Casey Barton Behravesh , Centers for Disease Control and Prevention, Atlanta, GA

Ian Williams , Centers for Disease Control and Prevention, Atlanta, GA

Laura Gieraltowski , Centers for Disease Control and Prevention, Atlanta, GA

BACKGROUND:

Salmonella causes approximately 1.2 million infections and 400 deaths annually in the United States. On June 13, 2013, PulseNet, a national molecular subtyping network for foodborne disease surveillance, identified a cluster of human infections of Salmonella Heidelberg with indistinguishable genetic fingerprints. States and CDC initiated an investigation to identify the source and prevent additional illnesses.

METHODS:

We defined a case as illness with an outbreak strain with onset March 1, 2013–present. Our investigation included collection of patient exposures and comparison to a population survey, isolate testing for antimicrobial resistance, and traceback and culture of retail chicken. United States Department of Agriculture’s (USDA) Food Safety and Inspection Service (FSIS) conducted intensified Salmonella testing at four production facilities.

RESULTS:

We identified 403 case-patients in 23 states and Puerto Rico; 40% (128/318) were hospitalized. A higher percentage (82% [51/61]) consumed chicken prepared at home than reported in the 2006-2007 FoodNet Population Survey, (65%, p-value <0.002); 80% (16/20) reported eating Foster Farms brand chicken. One sub-cluster was linked to Foster Farms-sourced rotisserie chicken from a single store location which subsequently recalled more than 23,000 units of rotisserie chicken products. Chicken products collected from Foster Farms facilities, Foster Farms retail chicken samples, and leftover case-patient food yielded the outbreak strains. Case-patient and poultry isolates were resistant to combinations of seven different antimicrobials, with 50 exhibiting multidrug resistance. On October 17, 2013, USDA-FSIS issued an alert about chicken from three Foster Farms facilities, reminding consumers to properly handle raw poultry. On October 11, 2013, Foster Farms began implementing process enhancements.

CONCLUSIONS:

This multidrug resistant Salmonella outbreak, in which epidemiologic, traceback, and laboratory evidence identified Foster Farms chicken as the source, highlights the need for more rigorous Salmonella control in raw chicken products. In response, Foster Farms implemented measures to decrease Salmonella burden in chicken parts, which may stimulate nationwide adoption of more stringent standards by other producers.