Epidemiological trend of methicillin-resistant staphylococcus aureus and emerging challenges for control

ABSTRACT

Following its first recognition in early 1960s, the increasing incidence of nosocomial and community - acquired methicillin-resistant Staphylococcus aureus [MRSA] infections has become a global problem. The emergence of multiple-drug resistant MRSA strains and dissemination of epidemic antibiotic clones including presence of wide spectrum of virulence and predisposing risk factors complicate diagnosis, chemotherapy and control causing significant morbidity and mortality. Resistance to methicillin is mediated by altered penicillin-binding protein 2a [PBP-2a], encoded by mec gene determinant [i.e. I-V types with different genomes, antibiograms and toxin profile] embedded in staphylococcal cassette chromosome [SCCmec]. It is also partly due to hyper beta-lactamase production by the organism. Detection of MRSA strains in domestic animals and associated persons including a wide spread protozoan has widened the organism's epidemiologic characters and may influence infection control policies. Routine and regular surveillance [uncommon in poor-resourced developing areas], good hospital practices and personal hygiene, development of effective therapeutic agents and rational administration of antibiotics based on reliable test results may cause limit in the spread of MRSA infections