19.12.2013

MMWR: December 6, 2013 / 62(48);979-982

On May 24, 2010, a cluster of 17 human Salmonella enterica serotype Chester clinical isolates with indistinguishable pulsed-field gel electrophoresis (PFGE) patterns was reported to PulseNet, the national molecular subtyping network for foodborne disease surveillance. This PFGE pattern had not been reported previously. Subsequently, CDC conducted an investigation that identified 44 ill persons in 18 states during May 24–June 19, 2010. In a multistate case-control study, consumption of a brand A frozen meal was associated with illness. On June 17, 2010, the manufacturer (company A) voluntarily recalled its brand A cheesy chicken and rice frozen meals. The outbreak strain of Salmonella Chester was isolated from eight unopened samples. A root cause analysis conducted by company A identified chicken as a possible contaminated ingredient. A total of 44 cases from 18 states were identified. Among 43 patients with available information, 16 (37%) were hospitalized; no deaths were reported. On June 17, 2010, CDC informed company A of the association between brand A cheesy chicken and rice frozen meals and the outbreak of Salmonella Chester infections. That day, the U.S. Department of Agriculture's Food Safety and Inspection Service (USDA-FSIS) convened its Recall Committee, and company A announced a recall of all brand A cheesy chicken and rice frozen meals, regardless of production date. The outbreak strain was later isolated from eight unopened brand A cheesy chicken and rice frozen meals with three production dates ranging from July 14, 2009 to March 12, 2010.