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Detection of qacA/B in Clinical Isolates of Methicillin-Resistant Staphylococcus aureus from a Regional Healthcare Network in the Eastern United States

  • Patrick McGann (a1), Yoon I. Kwak (a1), Amy Summers (a1), James F. Cummings (a2), Paige E. Waterman (a1) and Emil P. Lesho (a1)...

We describe the clinical, microbiologic, and molecular features of the first series of qacA/B-containing strains of methicillin-resistant Staphylococcus aureus from infected US patients. All qac-carrying strains were clonally diverse, and qacA strains exhibited increased tolerance to chlorhexidine as measured by minimum inhibitory concentrations, minimum bactericidal concentrations, and postexposure colony counts.

Corresponding author
Walter Reed Army Institute of Research, 503 Robert Grant Avenue, 1E06, Silver Spring, MD 20910 (
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Infection Control & Hospital Epidemiology
  • ISSN: 0899-823X
  • EISSN: 1559-6834
  • URL: /core/journals/infection-control-and-hospital-epidemiology
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