Multistate Outbreak of Human Salmonella Typhimurium Infections Associated With Aquatic Frogs—United States, 2009

During April-July 2009, the Utah Dpartment of Health identified five cases of Salmonella Typhimurium infection with indistinguishable pulsed-field gel electrophoresis (PEGE) patterns, predominantly among children. In August, CDC began a multistate outbreak investigation to determine the source of the infections. Here, Hall et al summarize the results of this ongoing investigation, which, as of December 30, had identified 85 S. Typhimurium human isolates with the outbreak strain from 31 states. In a multistate case-control study, exposure to frogs was found to be significantly associated with illness. A CDC editorial note is included.