Recipient Organization
OHIO STATE UNIVERSITY - VET MED
1900 COFFEY ROAD, 127L VMAB
COLUMBUS,OH 43210
Performing Department
Preventive Medicine
Non Technical Summary
The zoonotic transmission (from animals to humans and vice-versa) of Methicillin-resistant Staphylococcus aureus (MRSA), as well as the possibility that horses could be potential MRSA reservoirs, has created growing concern within the public health and veterinary communities. Retrospective and pilot studies have clearly shown that MRSA is prevalent in the horse population arriving to the OSU - Veterinary Teaching Hospital (VTH) and the hospitals' environment. However, the real prevalence and the characteristics of the MRSA strains in this population of horses is still unknown. Therefore, we propose to establish an active and passive surveillance system to monitor MRSA in equine patients, as well as the environment, that are admitted at the OSU-VTH. The epidemiological information obtained through this study will be very valuable to understand the epidemiology and ecology of this important pathogen in horse populations in veterinary settings, which will have significant implications to the veterinary and public health field.
Animal Health Component
50%
Research Effort Categories
Basic
50%
Applied
50%
Developmental
(N/A)
Goals / Objectives
Horses have been reported as the source of Methicillin-resistant Staphylococcus aureus (MRSA), in multiple zoonotic and nosocomial outbreaks primarily in veterinary hospitals. However, the real prevalence of MRSA in the horse population as well as important risk factors associated with this pathogen are largely unknown.A 3-year retrospective study (2004-2006) at the OSU - Veterinary Teaching Hospital (VTH), Clinical Microbiology Laboratory (CML), showed that of 32 Staphylococcus aureus infections in horses 16 (50%) were MRSA. This result clearly indicates that MRSA is prevalent in the horse population arriving at the OSU-VTH, which represents a major health risk for our patients, clients, students, staffs, and faculty. In this study, we propose to establish an active and passive surveillance system to monitor the hospital environment and equine patients, admitted at the OSU-VTH. The specific aims are: 1)Through active and passive surveillance, establish the prevalence and characteristics of MRSA isolates in equine patients admitted to the VTH. 2)Establish the frequency of isolation of methicillin-resistant Staphylococcus aureus (MRSA) from specific high-risk environments of the at the OSU Large Animal Veterinary Teaching Hospital (VTH). The results obtained from this experiment will be used to assist in the development of appropriate biosecurity and biosafety protocols to help prevent the transmission and colonization of patients, owners, students, employees, and faculty; as well as, to avoid the contamination of the environmental , therefore preventing nosocomial infections due to MRSA. These data will also be used to design future epidemiological studies to determine the prevalence of MRSA in the Ohio horse population.
Project Methods
1. Surveillance and characterization of MRSA in horses: This surveillance activity will be performed both actively and passively to establish the prevalence and characteristic of MRSA strains circulating among equine patients admitted to the VTH for surgery or other procedures. The first 8 horses admitted to each one of the three equine clinical specialties (internal medicine, intensive care unit, and surgery) will be sampled regardless of their health status at the time of admission. Equine samples will be collected by independently swabbing a pair of sterile cotton-tip culture swabs along the anterior nares (10cm deep and maintaining contact with the mucosa), the vulva/prepuce area, and the axillary area. An epidemiological survey will be performed to obtain relevant information about each horse being sampled, allowing the identification of risk factors associated with the presence of MRSA. This information will include age, sex, breed, reason for admission, previous treatments, and other pertinent information potentially related to MRSA. 2. Surveillance of MRSA in the environment: This research will be performed to establish the frequency and characteristics of MRSA in specific environments of the OSU-VTH, where the presence of MRSA will represent a major health risk for the patients admitted to these areas. Environmental samples will be collected in the equine internal medicine, intensive care unit, and surgery wards. At least 8 environmental samples from animal contact surfaces will be collected from every ward. Eight human contact surfaces per month will also be sampled in each one of the three areas. The sampling will be performed on the first week of every month for 12 months totaling 576 samples (48 samples from animal and human contact surfaces x 12 months). A similar set of environmental samples (n=8) as indicated above will be collected when a positive MRSA isolate is identified from both the patient(s) and/or the environment where the animal was located. Information about the patients (age, sex, breed, reason for admission, previous treatments, etc), use of the wards (equipment and cages), and cleaning procedures at sampling timing will be collected. The results of this surveillance program are primarily descriptive and will be summarized and displayed graphically as appropriate. In addition, changes in frequency of MRSA recovery over time will be assessed using the chi square test for trend as well as the Spearman nonparametric correlation coefficient to evaluate linear trend. Differences in frequency of recovery of MRSA between species, among sampling locations, or among other sources of isolates will be evaluated using multivariable logistic regression models to control for any potential confounding and colinearity among variables.