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Nasal colonization with methicillin-resistant Staphylococcus aureus: clinical implications and treatment

David Friedel1, Michael Climo

  • 1McGuire Veteran Affairs Medical Center, 1201 Broad Rock Boulevard, Section 111-C, Richmond, VA 23236, USA.

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Antibiotic resistance in bacteria arises when microorganisms evolve the ability to withstand drugs designed to kill them or inhibit their growth, rendering once-effective treatments useless. This phenomenon, driven by genetic change and selection under antibiotic exposure, poses a profound threat to modern medicine. Mechanisms include drug-inactivating enzymes (e.g., β-lactamases), efflux pumps that eject antibiotics, mutations altering antibiotic targets, decreased drug uptake, and acquisition...
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