*Contributed equally to this work.
Detection and Control of a Nosocomial Outbreak Caused by Salmonella Newport at a Large Animal Hospital
Article first published online: 15 MAR 2010
Copyright © 2010 by the American College of Veterinary Internal Medicine
Journal of Veterinary Internal Medicine
Volume 24, Issue 3, pages 606–616, May/June 2010
How to Cite
Steneroden, K.K., Van Metre, D.C., Jackson, C. and Morley, P.S. (2010), Detection and Control of a Nosocomial Outbreak Caused by Salmonella Newport at a Large Animal Hospital. Journal of Veterinary Internal Medicine, 24: 606–616. doi: 10.1111/j.1939-1676.2010.0484.x
- Issue published online: 7 MAY 2010
- Article first published online: 15 MAR 2010
- Submitted May 21, 2009; Revised December 11, 2009; Accepted January 28, 2010
- Bacterial species;
- Hospital surveillance;
- Infection control;
- Infectious diseases;
Background: Nosocomial salmonellosis is often assumed to occur because infection control and surveillance practices are inadequate, but published evidence is lacking to support the related contention that rigorous application of these practices can impact the severity of outbreaks.
Objective: Describe active surveillance, early recognition, and intensive mitigation efforts used in an effort to control an outbreak of nosocomial Salmonella enterica serotype Newport infections without hospital closure.
Animals: Large animals hospitalized at a referral hospital.
Methods: This prospective outbreak investigation was initiated when Salmonella Newport infections were detected among hospitalized animals by active surveillance. Data were analyzed to identify temporal and spatial patterns for epidemic spread of Salmonella in the hospital. Mitigation efforts were aggressively adjusted in response to surveillance data. Genetic relatedness of isolates was investigated by pulsed-field gel electrophoresis.
Results: Of 145 large animals sampled, 8 (5.6%) were infected with the Salmonella strain associated with this outbreak, and all but 1 shed Salmonella in the absence of or before the onset of disease. This strain was recovered from 14.2% (42/295) of environmental samples (ENV samples), indicating that widespread environmental contamination had occurred. Isolates of Salmonella Newport obtained from infected animals and the environment were genetically indistinguishable, confirming clonal dissemination.
Conclusions and Clinical Importance: Active surveillance allowed early detection of nosocomial Salmonella transmission and hospital contamination. Use of aggressive interventions was followed by cessation of transmission. Active surveillance can allow earlier recognition and mitigation compared with programs by only sampling of clinically affected animals.