Community-Associated Methicillin-ResistantStaphylococcus aureus: Epidemiology and Clinical Consequences of an Emerging Epidemic

Abstract

SUMMARY Staphylococcus aureus is an important cause of skin and soft-tissue infections (SSTIs), endovascular infections, pneumonia, septic arthritis, endocarditis, osteomyelitis, foreign-body infections, and sepsis. Methicillin-resistant S. aureus (MRSA) isolates were once confined largely to hospitals, other health care environments, and patients frequenting these facilities. Since the mid-1990s, however, there has been an explosion in the number of MRSA infections reported in populations lacking risk factors for exposure to the health care system. This increase in the incidence of MRSA infection has been associated with the recognition of new MRSA clones known as community-associated MRSA (CA-MRSA). CA-MRSA strains differ from the older, health care-associated MRSA strains; they infect a different group of patients, they cause different clinical syndromes, they differ in antimicrobial susceptibility patterns, they spread rapidly among healthy people in the community, and they frequently cause infections in health care environments as well. This review details what is known about the epidemiology of CA-MRSA strains and the clinical spectrum of infectious syndromes associated with them that ranges from a commensal state to severe, overwhelming infection. It also addresses the therapy of these infections and strategies for their prevention.

Low pH Enhances the Action of Maximin H5 against Staphylococcus aureus and Helps Mediate Lysylated Phosphatidylglycerol-Induced Resistance

“…Strains of the organism, including those with methicillin resistance, are responsible for the vast majority of bacterial skin infections in humans 84,85 and have developed multiple mechanisms to evade antibiotics 86,87 , the adaptive immune response and the action of endogenous AMPs 43,88 .…”

The role of vaccines in fighting antimicrobial resistance (AMR)

“…MRSA contributes to over 70,000 cases of invasive disease per year in the US alone. 45 Both the CDC and the WHO have recently placed MRSA on their AMR watch lists, highlighting the significance of AMR in this species. S. aureus has the propensity to develop resistance even to newer antibiotics that have been introduced such as linezolid and daptomycin 44 and S. aureus glycopeptide resistance has emerged as a source of concern, as this class of antibiotics, including vancomycin, is one of the main resources for combating infections caused by MRSA and reduced susceptibility to vancomycin already has been described.…”

Differing epidemiology of two major healthcare-associated meticillin-resistant Staphylococcus aureus clones

“…1 The acquisition of antimicrobial resistance provides a selective advantage in the nosocomial environment, and has complicated treatment regimens significantly. Today, MRSA is a major cause of morbidity and mortality in hospitals and the community.…”