Abstract
Staphylococcus aureus (S. aureus) is a significant Gram-positive bacterium found on the skin and mucous membranes of mammals. Although colonization is often asymptomatic in both humans and animals, it can shift to opportunistic infections. The high pathogenicity of the organism is occasioned by its numerous virulence factors. S. aureus is not just pathogenic, but can also develops fast resistance to new classes of antibiotics following multiple exposures. This review focuses on S. aureus, its virulence factors, epidemiology and antimicrobial resistance. The study also highlights the different strains of Methicillin-resistant S. aureus (MRSA) including the Hospital-associated MRSA, Community-associated MRSA and Livestock-associated MRSA, alongside the different clonal complexes associated with each strain showing the genetic diversity of S. aureus. The World Health Organization has included MRSA in the list of “priority pathogens” due to the widespread prevalence and severity of its infections. Vancomycin remains one of the first-line drugs for treatment of severe MRSA infections. Hand hygiene, screening, contact precautions, disinfection, wound and catheter management, perioperative antibiotic prophylaxis are very efficient preventive measures to reduce transmission and infection of S. aureus. Antimicrobial stewardship including periodic surveillance for resistant strains and avoidance of antibiotics use in food animals are effective control measures to combat antimicrobial menace of the organism.

Key words: Staphylococcus aureus, virulence, MRSA, antimicrobial resistance