Transmission Clusters of Methicillin-Resistant Staphylococcus Aureus in Long-Term Care Facilities Based on Whole-Genome Sequencing

O. Colin Stine, Shana Burrowes, Sophia David, J. Kristie Johnson, Mary Claire Roghmann

Research output: Contribution to journalArticlepeer-review


OBJECTIVE To define how often methicillin-resistant Staphylococcus aureus (MRSA) is spread from resident to resident in long-term care facilities using whole-genome sequencing DESIGN Prospective cohort study SETTING A long-term care facility PARTICIPANTS Elderly residents in a long-term care facility METHODS Cultures for MRSA were obtained weekly from multiple body sites from residents with known MRSA colonization over 12-week study periods. Simultaneously, cultures to detect MRSA acquisition were obtained weekly from 2 body sites in residents without known MRSA colonization. During the first 12-week cycle on a single unit, we sequenced 8 MRSA isolates per swab for 2 body sites from each of 6 residents. During the second 12-week cycle, we sequenced 30 MRSA isolates from 13 residents with known MRSA colonization and 3 residents who had acquired MRSA colonization. RESULTS MRSA isolates from the same swab showed little genetic variation between isolates with the exception of isolates from wounds. The genetic variation of isolates between body sites on an individual was greater than that within a single body site with the exception of 1 sample, which had 2 unrelated strains among the 8 isolates. In the second cycle, 10 of 16 residents colonized with MRSA (63%) shared 1 of 3 closely related strains. Of the 3 residents with newly acquired MRSA, 2 residents harbored isolates that were members of these clusters. CONCLUSIONS Point prevalence surveys with whole-genome sequencing of MRSA isolates may detect resident-to-resident transmission more accurately than routine surveillance cultures for MRSA in long-term care facilities.

Original languageEnglish (US)
Pages (from-to)685-691
Number of pages7
JournalInfection Control and Hospital Epidemiology
Issue number6
StatePublished - Jun 1 2016
Externally publishedYes

ASJC Scopus subject areas

  • Microbiology (medical)
  • Epidemiology
  • Infectious Diseases


Dive into the research topics of 'Transmission Clusters of Methicillin-Resistant Staphylococcus Aureus in Long-Term Care Facilities Based on Whole-Genome Sequencing'. Together they form a unique fingerprint.

Cite this