Salmonella outbreak in a nursing home.

We performed a retrospective review of an outbreak of Salmonella gastroenteritis that occurred in a community nursing home in 1987. Forty-four of 199 residents had a diarrheal illness; Salmonella heidelberg was isolated from the stool in 19 cases. Although the distribution of cases suggested a common source for the outbreak, no common source of infection could be demonstrated, despite extensive investigation. The clinical presentation of symptomatic individuals ranged from mild diarrhea to a severe gastrointestinal illness, and 26% of symptomatic, culture-positive patients required hospitalization. The median duration of pathogen excretion during convalescence in untreated residents was six weeks, but six patients who were treated with antibiotics shed S. heidelberg for a median duration of 14.5 weeks. We conclude that (1) the clinical spectrum of Salmonella gastroenteritis in nursing-home patients is variable, ranging from mild to severe illness; and (2) nursing-home Salmonella outbreaks impose a high economic burden because of expense of epidemiologic investigation, prolonged isolation measures, hospitalization for severely ill residents, and potential institutional closure.