Salmonella entericaSerovar 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. Nosocomial salmonellosis continues to pose an important threat to veterinary medical teaching hospitals.

Outbreak of multidrug resistant Salmonella Typhimurium in calves at a veterinary hospital in Brazil

“…isolates from outbreaks are commonly phenotypically similar, with shared antimicrobial susceptibility patterns and serotypes (BURGESS & MORLEY, 2014). In the present work, most isolates shared the same serotypes, antimicrobial resistance profile as well as genotypic patterns at ERIC-PCR, confirming its nosocomial transmission (BURGESS, MORLEY, 2014;CUMMINGS et al, 2014).…”

Resistance to Carbapenems in Non-Typhoidal Salmonella enterica Serovars from Humans, Animals and Food

“…Even though NTS have limited significance as human nosocomial pathogens, this is not the case in veterinary hospitals, where infections caused by these bacteria are an ongoing problem worldwide, particularly in equine patients [ 72 ]. In contrast to human medicine, carbapenems have never been licensed for use in livestock animals in any country [ 73 ].…”

Nosocomial Infections and their Surveillance in Veterinary Hospitals

“…A retrospective study with the faecal culture data conducted in a teaching veterinary hospital following an outbreak of salmonellosis with high percentage of cases within 24 hours of admission revealed the etiological agent was Salmonella enterica serovar Oranienburg. Severe scrutiny of their medical records exposed the concealed epidemiological association to the veterinary hospital following the index case (Cummings et al, 2014).…”