Prevalence of methicillin-resistant staphylococci in northern Colorado shelter animals

Methicillin-resistant Staphylococcus aureus (MRSA) and Staphylococcus pseudintermedius (MRSP) have been recognized as significant pathogens in veterinary medicine. There have been documented cases of MRSA infection and colonization in veterinary critical care units, in veterinary personnel, and in equine and feline patients. To date, there have been no studies examining the prevalence of MRSA or MRSP colonization of cats and dogs in animal shelters in the United States. The purpose of the current study was to determine the prevalence of MRSA and MRSP in cats and dogs in a northern Colorado animal shelter. Samples were collected from 200 cats and 200 dogs in an open admission shelter. Each species was divided into 2 smaller groups: 100 dogs or cats housed in the stray ward and 100 dogs or cats housed in the adoption area. Samples were evaluated for the prevalence of MRSA or MRSP, which was verified through aerobic culture and Kirby-Bauer agar disc diffusion to confirm antimicrobial sensitivity. Results revealed MRSA in 0.5% of cat samples, MRSA in 0.5% of dog samples, and MRSP in 3% of dog samples. These results are consistent with previously published prevalence rates for these 2 organisms in non-shelter populations of dogs and cats, indicating that cats and dogs from this Colorado shelter do not appear to pose any greater risk to the public than do cats and dogs in the general pet population.