Trends in Shigella outbreaks in the Israeli military over 15 years

Excerpt

A retrospective analysis was performed in order to detect trends in the role of Shigella in diarrheal outbreaks in the Israel Defense Force (IDF) over a 15-year period. Diarrhea was defined as the passage of three or more watery stools within a 24-h period. Diarrheal outbreaks were defined as events meeting any one of the following three defining criteria: (i) ten or more persons in a single unit developing diarrhea in a single day; (ii) 15 or more persons in a single unit developing diarrhea over a 2-day period; or (iii) 25% of the personnel in a single unit developing diarrhea within a 7-day period. Diarrheal outbreaks are a notifiable disease in the IDF, and the reporting mechanism, which remained unchanged throughout the study period, is comprehensive and nearly complete. Laboratory investigation of outbreaks is a routine component of the epidemiologic investigation, and bacteriologic culture protocols for stool and food samples remained constant throughout the study period. These included culturing stool samples for Shigella, Salmonella and Campylobacter spp. and culturing food samples for additional food-borne pathogens such as Staphylococcus spp. …