Correlation Between Genetic Resistance Factors and the Antibiotic Resistance Phenotypes in MRSA Isolates of Animals and Humans

Abstract Background: Methicillin resistant Staphylococcus aureus (MRSA) as an infectious organism of public health significance has evolved to a genetically distinct community-acquired MRSA with extended resistance to other than β-lactams. Methods: A cross-sectional study was conducted among 149 participants handling 446 animals (240 horses & 206 companion animals). The isolates were characterised as S. aureus and MRSA based on PCR detection of nuc, mecA or mecC, respectively and pvl gene for differentiation as community associated/livestock associated or hospital associated. Results: Isolation rates of S. aureus from the human handlers’ samples were 26 (17.4%) and 170 (38.1%) from the animal samples. The prevalence of MRSA among the isolates were 7 (4.7%) from the human handlers and 19 (4.3%) from the animals. Dogs and dog handlers had highest isolation rates and were more likely to be colonized by S. aureus and MRSA compared to horses, cats, and their handlers. The highest prevalence of MRSA was from horses (5.0%) and dog handlers (10.6%). Conclusion: This study has demonstrated a high prevalence of community associated MRSA in apparently healthy animals and their human handlers. This has important implication for antibiotic selection and usage as well as infection control measures.