ISOLATION, ANTIBIOGRAM AND CHARACTERIZATION OF VANCOMYCIN-RESISTANT STAPHYLOCOCCUS AUREUS FROM CLINICAL AND COMMUNITY ISOLATES IN ABAKALIKI, EBONYI STATE, NIGERIA

This study was aimed at isolating and characterizing vancomycin-resistant Staphylococcus aureus from clinical and community samples in Abakaliki, Ebonyi State, Nigeria. Seven hundred and nine (709) clinical and community samples were obtained for this study. Antibiotic susceptibility test was done using Kirby Bauer disc diffusion method. Vancomycin resistant Staphylococcus aureus (VRSA) isolates were detected using Kirby-Bauer disc diffusion method with vancomycin antibiotic disc (30 μg). Isolates were also screened for β-lactamase enzyme production. A total of 84 (27.7 %) and 120 (29.5 %) Staphylococcus aureus isolates were obtained from the clinical and community samples respectively using standard microbiological techniques. Results showed that 55 VRSA isolates were obtained from the samples with prevalence frequency of 36.9 % and 20 % for clinical and community isolates respectively. The clinical isolates were completely resistant (100 %) to nitrofurantoin, clindamycin, ceftazidime, tetracycline and penicillin. Gentamicin was the most effective antibiotic against the S. aureus isolates obtained from clinical samples as all the isolates were completely susceptible (100 %). Ciprofloxacin was the most effective antibiotic against the S. aureus isolates obtained from community samples with a susceptibility frequency of 100 %. This was closely followed by gentamicin (75 %) and erythromycin. Exactly 38.1 % and 24.2 % of the clinical and community S. aureus isolates were positive for beta-lactamase production respectively. The HA-VRSA and CA-VRSA isolates had MARI values within the range of 0.5 to 1.0. This present discovery of multi-drug resistant VRSA with high multiple antibiotic resistance indices is in Abakaliki is a serious public health issue. Therefore, there is an urgent need to keep a strict watch on VRSA emerging from Abakaliki. Keywords: CA-VRSA, HA-VRSA, MARI, beta-lactamase, antibiotics