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Subcutaneous Infection of Methicillin Resistant Staphylococcus Aureus (MRSA)
12:18

Subcutaneous Infection of Methicillin Resistant Staphylococcus Aureus (MRSA)

Published on: February 9, 2011

Community-associated methicillin-resistant Staphylococcus aureus and healthcare risk factors

R Monina Klevens1, Melissa A Morrison, Scott K Fridkin

  • 1Centers for Disease Control and Prevention, Atlanta, Georgia 30333, USA. rmk2@cdc.gov

Emerging Infectious Diseases
|March 1, 2007
PubMed

Insights

Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) strains, like USA300, are frequent causes of infection in patients with healthcare-related risk factors (HRFs). This challenges traditional distinctions between community- and healthcare-associated MRSA infections.

Area of Science:

  • Infectious Diseases
  • Microbiology
  • Epidemiology

Background:

  • Methicillin-resistant Staphylococcus aureus (MRSA) is a significant pathogen.
  • Distinguishing between community-associated (CA) and healthcare-associated (HA) MRSA is important for treatment and control.
  • Specific MRSA strains, such as USA300 (CA) and USA100 (HA), are typically linked to different settings.

Purpose of the Study:

  • To investigate the frequency of community-associated MRSA (CA-MRSA) strains, specifically USA300, in patients with healthcare-related risk factors (HRFs).
  • To assess the overlap between MRSA strain types and patient risk factors.

Main Methods:

  • Analysis of surveillance data for MRSA infections.
  • Categorization of patients based on the presence or absence of healthcare-related risk factors (HRFs).
  • Identification of MRSA strain types, focusing on USA300 and USA100 designations.

Main Results:

  • Among patients with HRFs, 18%-28% harbored MRSA strains typically associated with community-acquired infections, primarily USA300.
  • Conversely, among patients without HRFs, 26% were infected with MRSA strains typically considered healthcare-associated, predominantly USA100.
  • These findings indicate a significant proportion of CA-MRSA infections in individuals with HRFs.

Conclusions:

  • The prevalence of USA300 strains in patients with HRFs suggests a blurring of the lines between community- and healthcare-associated MRSA.
  • Healthcare-related risk factors do not preclude infection with community-associated MRSA strains.
  • Epidemiological surveillance and clinical management strategies may need to account for this overlap.

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