TY - JOUR
T1 - Correlation between animal nasal carriage and environmental methicillin-resistant Staphylococcus aureus isolates at U.S. horse and cattle farms
AU - Peterson, Amy E.
AU - Davis, Meghan F.
AU - Awantang, Grace
AU - Limbago, Brandi
AU - Fosheim, Gregory E.
AU - Silbergeld, Ellen K.
N1 - Funding Information:
This work was supported by a Johns Hopkins Center for a Livable Future Innovation Grant . AEP and MFD thank the Center for a Livable Future and MFD additionally thanks the Hopkins Sommer Scholar program for tuition and related financial support. Portions of this work were presented previously at the 2009 ASM-ESCMID Conference on Methicillin-resistant Staphylococci in Animals.
PY - 2012/12/7
Y1 - 2012/12/7
N2 - Animals on farms may be a potential reservoir and environmental source of methicillin-resistant Staphylococcus aureus (MRSA). Expanded surveillance methods for animal-associated MRSA are needed. To develop an environmental sampling method and to determine the correlation between animal and environmental MRSA positivity in the farm setting, we sampled horses, cattle, and their local environments at several farms in the mid-Atlantic United States. We obtained nasal swabs from 13 racehorses at first visit, and 11 racehorses at the same farm eight weeks later. We also sampled 26 pleasure horses and 26 beef cattle from two additional farm sites. Sterilized electrostatic cloths were used to collect dry dust samples from environmental surfaces in proximity to animals; cloths were cultured using a broth enrichment protocol. We described isolates by genotype and antimicrobial susceptibility phenotype. None of the samples (nasal or environmental) were positive from the pleasure horse farm or the cattle farm. On the racehorse farm, 8/13 (61%) nasal and 5/7 (71%) environmental samples were positive for MRSA at the first visit. Isolates found were indistinguishable by pulsed-field gel electrophoresis (PFGE) genotype. We observed significant positive correlation between nasal carriage of MRSA in animals and our ability to isolate MRSA from dry surface samples of their local environments. The methods presented here may aid in surveillance efforts for equine and other animal MRSA. This study successfully applies existing MRSA surveillance methods for indoor, high animal density settings to outdoor and low-density farms.
AB - Animals on farms may be a potential reservoir and environmental source of methicillin-resistant Staphylococcus aureus (MRSA). Expanded surveillance methods for animal-associated MRSA are needed. To develop an environmental sampling method and to determine the correlation between animal and environmental MRSA positivity in the farm setting, we sampled horses, cattle, and their local environments at several farms in the mid-Atlantic United States. We obtained nasal swabs from 13 racehorses at first visit, and 11 racehorses at the same farm eight weeks later. We also sampled 26 pleasure horses and 26 beef cattle from two additional farm sites. Sterilized electrostatic cloths were used to collect dry dust samples from environmental surfaces in proximity to animals; cloths were cultured using a broth enrichment protocol. We described isolates by genotype and antimicrobial susceptibility phenotype. None of the samples (nasal or environmental) were positive from the pleasure horse farm or the cattle farm. On the racehorse farm, 8/13 (61%) nasal and 5/7 (71%) environmental samples were positive for MRSA at the first visit. Isolates found were indistinguishable by pulsed-field gel electrophoresis (PFGE) genotype. We observed significant positive correlation between nasal carriage of MRSA in animals and our ability to isolate MRSA from dry surface samples of their local environments. The methods presented here may aid in surveillance efforts for equine and other animal MRSA. This study successfully applies existing MRSA surveillance methods for indoor, high animal density settings to outdoor and low-density farms.
KW - Cattle
KW - Environmental microbiology
KW - Horses
KW - Methicillin-resistant Stapylococcus aureus
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U2 - 10.1016/j.vetmic.2012.06.032
DO - 10.1016/j.vetmic.2012.06.032
M3 - Article
C2 - 22795260
AN - SCOPUS:84869086335
SN - 0378-1135
VL - 160
SP - 539
EP - 543
JO - Veterinary Microbiology
JF - Veterinary Microbiology
IS - 3-4
ER -