WORLD JOURNAL OF ADVANCE
HEALTHCARE RESEARCH

Unyime C. Essien*, Samar S. Boswihi, Nneka R. Agbakoba and Edet E Udo

ABSTRACT

Background: Methicillin resistant S. aureus (MRSA) constitutes a serious public health problem in hospitals and community settings. Knowledge of local data on antibiotic resistance of MRSA isolates is important for empiric antibiotic prescription. Aim: To determine the prevalence, clonal composition, antibiotic resistance and virulence profiles of MRSA obtained from patients in tertiary hospitals in Jos, Nigeria. Method: A total of 214 S. aureus isolates were tested for susceptibility to antibacterial agents by the disc diffusion method and determination of the minimum inhibitory concentration (MIC). Methicillin resistance was confirmed by the PCR amplification of mecA gene. The MRSA were genotyped using spa typing, multilocus sequence typing (MLST) and DNA microarray analysis. Results: Forty-seven (21.9%) of the 214 isolates were positive for mecA. Most of the MRSA isolates were cultured from wound 27 (57.4%) and urine 11 (23.4%) specimens of males (n=27 (57.4%) of age group 11-29 (n=30; 63.8%). The isolates were resistant to penicillin G and trimethoprim mediated by blaZ and dfrS1, respectively. All MRSA were identified as CA-MRSA (SCCmec type IV=4; SCCmec type V=43) by SCC mec typing. The MRSA belonged to 10 spa types with t008 (n=14; 29.8%) as the dominant spa type, followed t064 and t2658 (n=7; 14.9%), and six sequence types, ST8 (n=28), ST772 (n=6), ST7 and ST152 (n=5), ST22 (n=2) and ST88 (n=1). The common genotypes were ST8-MRSA-V-t008/t064/t2658 (n=27), ST772-MRSA-V, [PVL+]/t657/t345 (n=6), ST7-MRSA-V-t091 (n=5) and ST152-MRSA-V//t355/t4690 (n=5), whereas ST22-MRSA-IV [tst1+]/t032 (n=2) and ST88-MRSA-IV /t786 (n=1) were less common. Conclusion: The study revealed a MRSA prevalence of 21.9%. The MRSA isolates belonged to diverse genetic backgrounds dominated by ST8-MRSA-V-t008/t064/t2658 genotype. The study has provided a platform for future studies on the molecular characteristics of MRSA in the central region of Nigeria.