Abstract
Background: Methicillin resistant Staphylococcus species such as S. aureus (MRSA) and S. pseudintermedius (MRSP) can be involved in life-threatening multidrug resistant infections in companion animals. Knowledge of methicillin resistant Staphylococcus (MRS) carriage and factors influencing carriage in companion animals from South East Queensland is limited. Nasal and rectal swab samples were collected from dogs, cats and horses upon admission or within 24 hours of hospitalisation to several primary accession and referral veterinary practices between November 2015 and December 2017. MRSA and MRSP were identified using standard microbiological (Brilliance selective medium) and molecular (mecA gene PCR) methods. Risk factors associated with methicillin resistant Staphylococcus (MRS) carriage were quantified using Bernoulli logistic regression models. A Bayesian geostatistical model was developed to predict the probability of MRS carriage in Brisbane and surrounding areas. Results: Our results indicated that while the prevalence of MRSP carriage in dogs was 8.7% (35/402) no MRSP was isolated from cats (0/69) and horses (0/60); no MRSA was isolated in any species. MRSP carriage in dogs was significantly associated with previous hospitalisation, previous bacterial infection, consultation type, average precipitation, and human population density. Our predictive map of MRSP carriage indicated that the probability of carriage was highest along the coastal areas of Greater Brisbane, particularly Brisbane city, Sunshine Coast and Gympie areas. Conclusions: This study determined that MRSP carriage in dog populations from South East Queensland is geographically clustered and associated with both clinical and environmental factors.
Evaluation of a new selective medium for methicillin-resistant Staphyloccocus aureus
