Antibiotics resistance profile of Staphylococcus aureus isolated from selected surfaces in a university campus

Abstract

Antibiotic-resistant bacteria are serious public health concern. Methicillin-resistant Staphylococcus aureus (MRSA) infections are steadily increasing but the potential reservoir and risk in the environment are poorly investigated. A total of 284 environmental swabs were collected from 2 faculties of the University and screened for the presence of S. aureus by standard biochemical assays, 16S rRNA and S. aureus nuc gene amplification for the molecular identification of the isolates. Antibiotic susceptibility test was done by disc diffusion method while the detection of resistance and virulence genes were investigated by Polymerase Chain Reaction (PCR). Of the total sample collected, 190 (47.50%) S. aureus were recovered of which > 80% were resistant to more than 3 antibiotics. Considerable resistance profile was observed among the isolates and there were positive amplifications for aph (3’)-IIIa and aac (6’)-Ie-aph (2’), ermB tetL and tetK genes. There was no amplification for the investigated virulence genes among the isolates. High presence of multiply resistant S. aureus from environmental surfaces suggests the campus environment is a potential reservoir of S. aureus infection

Keywords: Antimicrobial Resistance, Staphylococcus aureus, virulence, antibiotics.