A rare outbreak of food poisoning caused by Salmonella enterica serovar. Oranienburg--a case report and features of isolates

A rare food poisoning outbreak caused by S. Oranienburg occurred at a junior high school athletic meet in Kurashiki, Okayama, in September 2005. The 70 patients included junior high school students, teachers and other school staff, and their families. This bacillus was isolated from stools of two employees and another in catered sandwiches. The cause of the outbreak was determined by evidence and epidemiological investigation to be sandwiches served at the athletic meet. Biochemical features, sensitivity to 12 antibacterial agents, and DNA patterns determined by pulse field gel electrophoresis (PFGE) and enterobacterial repetitive intergenic sequence PCR (ERIC2-PCR) agreed for all isolates from outbreak samples. Isolates resembled strains isolated from broilers and a patient stool in an outbreak involving cuttlefish chips from 1998 to 1999 in Okayama Prefecture. A number of differences in strains isolated from broilers, chicken appendix content, and feed were detected in 2004, so we concluded that few outbreaks of food poisoning occurred due to S. Oranienburg in Okayama, attention is required for food poisoning by S. Oranienburg in the future because the dissemination of S. Oranienburg strains showing different features has been confirmed.