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Molecular tracing of the emergence, adaptation, and transmission of hospital-associated methicillin-resistant Staphylococcus aureus

Research output: Contribution to journalArticle

  • P. R. McAdam
  • K. E. Templeton
  • G. F. Edwards
  • M. T. Holden
  • E. J. Feil
  • D. M. Aanensen
  • H. J. Bargawi
  • B. G. Spratt
  • S. D. Bentley
  • J. Parkhill
  • M. C. Enright
  • A. Holmes
  • E. K. Girvan
  • P. A. Godfrey
  • M. Feldgarden
  • A. M. Kearns
  • A. Rambaut
  • D. A. Robinson
  • J. R. Fitzgerald

Related Edinburgh Organisations

Original languageEnglish
Pages (from-to)9107-9112
Number of pages5
JournalProceedings of the National Academy of Sciences (PNAS)
Issue number23
Publication statusPublished - Jun 2012


Hospital-associated infections caused by methicillin-resistant Staphylococcus aureus (MRSA) are a global health burden dominated by a small number of bacterial clones. The pandemic EMRSA-16 clone (ST36-II) has been widespread in UK hospitals for 20 y, but its evolutionary origin and the molecular basis for its hospital association are unclear. We carried out a Bayesian phylogenetic reconstruction on the basis of the genome sequences of 87 S. aureus isolates including 60 EMRSA-16 and 27 additional clonal complex 30 (CC30) isolates, collected from patients in three continents over a 53-y period. The three major pandemic clones to originate from the CC30 lineage, including phage type 80/81, Southwest Pacific, and EMRSA-16, shared a most recent common ancestor that existed over 100 y ago, whereas the hospital-associated EMRSA-16 clone is estimated to have emerged about 35 y ago. Our CC30 genome-wide analysis revealed striking molecular correlates of hospital- or community-associated pandemics represented by mobile genetic elements and nonsynonymous mutations affecting antibiotic resistance and virulence. Importantly, phylogeographic analysis indicates that EMRSA-16 spread within the United Kingdom by transmission from hospitals in large population centers in London and Glasgow to regional health-care settings, implicating patient referrals as an important cause of nationwide transmission. Taken together, the high-resolution phylogenomic approach used resulted in a unique understanding of the emergence and transmission of a major MRSA clone and provided molecular correlates of its hospital adaptation. Similar approaches for hospital-associated clones of other bacterial pathogens may inform appropriate measures for controlling their intra- and interhospital spread.

    Research areas

  • nosocomial, epidemiology

ID: 3144700