Nosocomial Salmonella epidemic.

A patient admitted to the hospital with diarrhea due to Salmonella heidelberg subsequently developed fatal disseminated salmonellosis, despite vigorous antimicrobial treatment. Beginning five weeks after the initial patient's death, nine patients developed hospital-acquired S heidelberg infections characterized by diarrhea (in seven) and bacteremia (in two). A careful search for salmonellosis among patients and hospital staff revealed two asymptomatic excretors. Extensive culturing of samples from the environment did not show any contaminated objects or reservoirs. The epidemic ended after initiation of an energetic handwashing campaign and isolation procedures. The strain of S heidelberg isolated was resistant to chloramphenicol, ampicillin, and gentamicin. Especially interesting in the epidemic were the prolonged time between death of the index case and the appearance of nosocomial cases, the high fatality rate, and the marked antibiotic resistance.