DOGS NOSTRILS

Methicillin-resistant Staphylococcus aureus (MRSA) is a significant opportunistic pathogen and a public health concern due to its multidrug-resistant nature and potential for zoonotic transmission. This study investigated the prevalence and antimicrobial susceptibility of MRSA in apparently healthy dogs in Ekosodin, Benin City, Edo State, Nigeria. A total of 160 dogs were sampled, and nasal swabs were processed using standard microbiological techniques. Staphylococcus aureus isolates were identified based on colonial morphology, Gram staining, and biochemical tests (catalase and coagulase). Methicillin resistance was determined phenotypically using cefoxitin (30 µg), while antibacterial susceptibility testing was performed using the modified Kirby-Bauer disc diffusion method. Out of the 160 dogs sampled, 146 (91.3%) were positive for S. aureus, and 142 (97.3%) were confirmed as MRSA, corresponding to an overall MRSA prevalence of 88.8%. MRSA carriage was highest in dogs aged 0–1 year (100%), and gender had no significant effect on prevalence. Antimicrobial susceptibility testing revealed high resistance among MRSA isolates to amoxicillin, erythromycin, cefuroxime, ceftazidime, gentamicin, streptomycin, azithromycin, and fluoroquinolones, with partial sensitivity retained for rifampicin (58.1%), ciprofloxacin
(46.5%), and levofloxacin (51.2%). MSSA isolates were generally more susceptible, showing statistically significant higher sensitivity to ciprofloxacin, levofloxacin, erythromycin, and cefuroxime (with p-value of 0.047, 0.004 and 0.005 respectively). These findings highlight the widespread carriage of multidrug-resistant MRSA among dogs in the study area, underscoring the need for prudent antibiotic use, improved hygiene, and public awareness to mitigate potential zoonotic transmission.