Methicillin-resistant Staphylococcus aureus : An update on the epidemiology, treatment options and infection control

Abstract

Methicillin-resistant Staphylococcus aureus (MRSA) is a major pathogen in hospitals and the community. In the past, most of the infections caused by MRSA were confined to elderly patients in healthcare facilities and they were described as healthcare-associated MRSA (HA-MRSA). However, the epidemiology of MRSA changed overtime with the emergence of strains in patients with no previous history of hospitalization which were known as community-associated MRSA (CA-MRSA). CA-MRSA strains are more genetically diverse and belong to different clones than HA-MRSA. Some clonal complexes are epidemic and are spread internationally while others are restricted to certain regions. The spread of epidemic MRSA clones globally is of concern since it limits antibiotic options for treating MRSA infections. Vancomycin has remained the drug of choice for the treatment of MRSA infections. However, in recent years the emergence of vancomycin-resistant S. aureus (VRSA) has posed additional limits to treat infections caused by MRSA. Consequently, new antibiotics have been developed and licensed for the treatment of MRSA infections. Despite the development of new antibiotics, the battle against resistance continues as long as antibiotics are misused. This requires strict implementation of antibiotic stewardship programs which provide tools and guidelines to help clinicians choose the right antibiotics at the right time for the right duration and that to control antimicrobial resistance.