Global spread of vancomycin-resistant Enterococcus faecium from distinct nosocomial genetic complex

Emerg Infect Dis. 2005 Jun;11(6):821-8. doi: 10.3201/1106.041204.

Abstract

Vancomycin-resistant enterococci (VRE) have caused hospital outbreaks worldwide, and the vancomycin-resistance gene (vanA) has crossed genus boundaries to methicillin-resistant Staphylococcus aureus. Spread of VRE, therefore, represents an immediate threat for patient care and creates a reservoir of mobile resistance genes for other, more virulent pathogens. Evolutionary genetics, population structure, and geographic distribution of 411 VRE and vancomycin-susceptible Enterococcus faecium isolates, recovered from human and nonhuman sources and community and hospital reservoirs in 5 continents, identified a genetic lineage of E. faecium (complex-17) that has spread globally. This lineage is characterized by 1) ampicillin resistance, 2) a pathogenicity island, and 3) an association with hospital outbreaks. Complex-17 is an example of cumulative evolutionary processes that improved the relative fitness of bacteria in hospital environments. Preventing further spread of this epidemic E. faecium subpopulation is critical, and efforts should focus on the early disclosure of ampicillin-resistant complex-17 strains.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Africa / epidemiology
  • Animals
  • Australia / epidemiology
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism
  • Cats
  • Cattle
  • Cross Infection / epidemiology
  • Cross Infection / microbiology
  • Cross Infection / transmission*
  • Dogs
  • Enterococcus faecium / classification
  • Enterococcus faecium / drug effects*
  • Enterococcus faecium / genetics
  • Enterococcus faecium / pathogenicity
  • Europe / epidemiology
  • Evolution, Molecular
  • Gram-Positive Bacterial Infections / epidemiology
  • Gram-Positive Bacterial Infections / microbiology
  • Gram-Positive Bacterial Infections / transmission*
  • Humans
  • North America / epidemiology
  • Penicillin Resistance
  • Recombination, Genetic
  • South America / epidemiology
  • Vancomycin Resistance*

Substances

  • Bacterial Proteins