Outbreak of Multidrug-Resistant Salmonella Infections Linked to Pork — Washington, 2015

During June-July 2015, Public Health-Seattle & King County and Washington State Department of Health investigated 22 clusters of Salmonella serotype I 4,(5), 12:i:- infections. Serotype I 4,(5), 12:i:- is the fifth most frequently reported Salmonella serotype in the US, but is uncommon in Washington. On Jul 29, 2015, WADOH and PHSKC requested assistance from CDC to identify the infection source, determine risk factors, and make recommendations for prevention. On the basis of cases investigated before August 2015, a supplemental questionnaire that went into more detail in addressing meat and livestock exposures was developed. Further study of the epidemiology and etiology of ASSuT resistance and Salmonella I 4,[5], 12:i:- is recommended. This was the largest Salmonella outbreak in Washington in recent history, and highlights that pork is an important source for human Salmonella infections. Best practices in all parts of the pork production industry, from farm to processing plant, can help reduce the risk for future outbreaks.