Two multistate outbreaks of Shiga toxin--producing Escherichia coli infections linked to beef from a single slaughter facility - United States, 2008.

During May-August 2008, state and local health and agriculture departments, the U.S. Department of Agriculture's Food Safety and Inspection Service (FSIS), and CDC investigated two multistate outbreaks of Shiga toxin--producing Escherichia coli O157 (STEC O157) with distinct pulsed-field gel electrophoresis (PFGE) patterns. Investigations into each outbreak included epidemiologic analysis of food exposures, microbiologic testing, and food distribution tracebacks. This report summarizes the results of those investigations. During May 27-August 25, 2008, a total of 99 persons (64 from the first outbreak and 35 from the second outbreak) from 18 states had confirmed illness with an STEC O157 isolate indistinguishable from the outbreak PFGE patterns. A case-control study conducted as part of the first investigation found a statistically significant association with purchase of ground beef from one large grocery chain (matched odds ratio [mOR] = 9.3). Traceback investigations for both outbreaks led to the same slaughter facility, resulting in multiple nationwide recalls of ground beef, intact beef, and beef products used to produce ground beef. This is the first report of two distinct STEC O157 outbreaks traced to a single slaughter facility and the first documented report of outbreaks linked to STEC O157 contamination of intact beef cuts ground by a retail chain. To help reduce the risk for outbreaks of STEC O157, the public health community should continue to educate consumers regarding the proper measures to take when handling and consuming ground beef.