Methicillin-resistant Staphylococcus aureus bacteraemia, 2003–2015: Comparative evaluation of changing trends in molecular epidemiology and clinical outcomes of infections

Methicillin-resistant Staphylococcus aureus (MRSA) is a prominent pathogen causing invasive infections such as bacteraemia. The continued excessive use of antibiotics to treat MRSA infections has resulted in the evolution of antimicrobial resistant of S. aureus. This study aims to perform a comparative evaluation of changing trends in molecular epidemiology of MRSA and clinical characteristics of patients. This study shows that ST22-MRSA-IV has gradually replaced ST239-MRSA-III as the predominant MRSA clone in the tertiary teaching hospital studied. Independent predictors of mortality among patients included devices in situ at the time of infection, pre-exposure to macrolides, catheter-related bloodstream infection and mono-microbial infection. Hence, our study affirmed community-associated MRSA, which was previously identified from individuals without any exposure to healthcare settings, has now emerged in healthcare settings, causing healthcare-associated MRSA infections. •ST22-MRSA-IV has gradually replaced ST239-MRSA-III as the predominant MRSA clone•Independent predictors of mortality among patients: devices in situ at the time of infection, pre-exposure to macrolides, catheter related bloodstream infection and mono-microbial infection•Increasing trend was observed in SCCmec type IV and Panton-Valentine leucocidin (pvl) gene carriage among the MRSA from 2013 to 2015