A review of nosocomial Salmonella outbreaks: infection control interventions found effective

To review nosocomial salmonellosis outbreaks to identify: mode of transmission; morbidity and mortality patterns; and recommendations for control and prevention.

Documented nosocomial salmonellosis outbreaks in hospitals published from January 1995 to November 2011, written in the English language, were systematically reviewed.

The study methodology incorporated steps from the PRISMA statement for a high quality review process. Computer-aided searches of Scopus, CAB Global Health and CINAHL(®), the Cumulative Index to Nursing and Allied Health Literature were completed to identify relevant outbreak reports written in English. To validate the electronic search methodology, bibliographies and reference lists of relevant review articles were hand-searched. Public health and government websites were searched for nosocomial salmonellosis.

Fifty-two relevant reports were identified. The most frequently reported routes of transmission were food 31/52 (59.6%) and person-to-person transmission 7/52 (13.5%). Actions taken during the outbreak to control transmission included improvements to: 1) infection control practices (41.8% of actions); isolation or cohorting patients, hand hygiene practices, and enhancing cleaning and disinfection in patient care areas; and 2) food handling practices (24.4% of actions); reviewing food preparation practices, enhancing cleaning and sanitation of the kitchen, and controlling food temperatures. Investigators made recommendations retrospectively in outbreak reports to provide direction to health centees but these recommendations were not statistically evaluated for effectiveness.

More emphasis should be placed on improving food handling practices, such as training food workers, monitoring food temperatures, and not using raw foods of animal origin, to prevent nosocomial salmonellosis outbreaks in hospitals because almost 60% of the outbreaks were foodborne.