Environmental Investigation and Genetic Analysis of Nosocomial Transmission of Methicillin-Resistant Staphylococcus aureus

Abstract

  Three methicillin-resistant Staphylococcus aureus (MRSA) clinical isolates were identified in one ward of our hospital from February to March 2014. These 3 MRSA strains were isolated 48 hours or more after hospital admission. Antibiogram and PCR-based open-reading frames typing methods revealed that 4 MRSA strains which contained 1 strain isolated from a long-term inpatient originated from one clone. We carried out an environmental investigation of the ward to reveal the source and route of the nosocomial transmission of MRSA. Four MRSA strains isolated from the environment of this ward and were from the same clone, indicating that dissemination within the environment of this ward was responsible for the spread of MRSA. This nosocomial transmission was terminated by the intervention of the infection control team including environment improvement. This study shows that identification of the source and route of the spread is important to prevent nosocomial transmission.