title: Salmonella enterica serovar Oranienburg outbreak in a veterinary medical teaching hospital with evidence of nosocomial and on-farm transmission.
abstract: Nosocomial salmonellosis continues to pose an important threat to veterinary medical teaching hospitals. The objectives of this study were to describe an outbreak of salmonellosis caused by Salmonella enterica serovar Oranienburg within our hospital and to highlight its unique features, which can be used to help mitigate or prevent nosocomial outbreaks in the future. We retrospectively analyzed data from patients that were fecal culture-positive for Salmonella Oranienburg between January 1, 2006, and June 1, 2011, including historical, clinical, and pulsed-field gel electrophoresis (PFGE) data. Salmonella Oranienburg was identified in 20 horses, five alpacas, and three cows during this time frame, with dates of admission spanning the period from August, 2006, through January, 2008. We consider most of these patients to have become infected through either nosocomial or on-farm transmission, as evidenced by molecular subtyping results and supportive epidemiologic data. Interpretation of PFGE results in this outbreak was challenging because of the identification of several closely related Salmonella Oranienburg subtypes. Furthermore, a high percentage of cases were fecal culture-positive for Salmonella Oranienburg within 24 h of admission. These patients initially appeared to represent new introductions of Salmonella into the hospital, but closer inspection of their medical records revealed epidemiologic links to the hospital following the index case. Cessation of this outbreak was observed following efforts to further heighten biosecurity efforts, with no known cases or positive environmental samples after January, 2008. This study demonstrates that a Salmonella-positive culture result within 24 h of admission does not exclude the hospital as the source of infection, and it underscores the important role played by veterinary medical teaching hospitals as nodes of Salmonella infection that can promote transmission outside of the hospital setting.
authors.affiliation: 1 Department of Veterinary Integrative Biosciences, Texas A&M University , College Station, Texas.
authors.forename: Kevin J
authors.initials: KJ
authors.lastname: Cummings
authors.forename: Lorraine D
authors.initials: LD
authors.lastname: Rodriguez-Rivera
authors.forename: Katharyn J
authors.initials: KJ
authors.lastname: Mitchell
authors.forename: Karin
authors.initials: K
authors.lastname: Hoelzer
authors.forename: Martin
authors.initials: M
authors.lastname: Wiedmann
authors.forename: Patrick L
authors.initials: PL
authors.lastname: McDonough
authors.forename: Craig
authors.initials: C
authors.lastname: Altier
authors.forename: Lorin D
authors.initials: LD
authors.lastname: Warnick
authors.forename: Gillian A
authors.initials: GA
authors.lastname: Perkins
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002161:Camelids, New World / Q000382:microbiology*; D002417:Cattle; D002418:Cattle Diseases / Q000453:epidemiology* / Q000382:microbiology / Q000635:transmission; D003428:Cross Infection / Q000662:veterinary; D004196:Disease Outbreaks / Q000662:veterinary*; D024901:Drug Resistance, Multiple, Bacterial; D016521:Electrophoresis, Gel, Pulsed-Field / Q000662:veterinary; D005243:Feces / Q000382:microbiology; D005260:Female; D006734:Horse Diseases / Q000453:epidemiology* / Q000382:microbiology / Q000635:transmission; D006736:Horses; D006762:Hospitals, Animal; D009518:New York / Q000453:epidemiology; D012189:Retrospective Studies; D012481:Salmonella Infections, Animal / Q000453:epidemiology* / Q000382:microbiology / Q000635:transmission; D019779:Salmonella enterica / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification*; D065288:Serogroup
chemical_list: D000900:Anti-Bacterial Agents
keywords: Epidemiology; Nosocomial; Salmonella; Veterinary hospital; Zoonotic