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Updated: Aug 11, 2026
12:18
Subcutaneous Infection of Methicillin Resistant Staphylococcus Aureus (MRSA)
Published on: February 9, 2011
Methicillin-resistant Staphylococcus aureus as a community organism
F Moreno1, C Crisp, J H Jorgensen
1Department of Medicine, University of Texas Health Science Center at San Antonio, USA.
Summary
Community-acquired methicillin-resistant Staphylococcus aureus (MRSA) infections were common, with a 2:1 ratio compared to hospital-acquired cases. Most MRSA strains were distinct, indicating diverse origins in this southern Texas university hospital study.
Area of Science:
- Infectious Diseases
- Microbiology
- Epidemiology
Background:
- Rising incidence of methicillin-resistant Staphylococcus aureus (MRSA) infections necessitates understanding transmission dynamics.
- MRSA poses a significant challenge in both community and healthcare settings.
Purpose of the Study:
- To investigate the epidemiology and risk factors of MRSA infections over a 21-month period.
- To differentiate community-acquired MRSA from nosocomial MRSA and identify distinct strains.
Main Methods:
- A case-control study compared community MRSA with community methicillin-susceptible S. aureus (MSSA).
- Pulsed field gel electrophoresis (PFGE) was used for DNA typing of MRSA isolates.
- MRSA cases were categorized as community, nosocomial, or transfer.
Main Results:
- An incidence of 0.2 MRSA cases per 1,000 patient-days was observed.
- Community-acquired MRSA cases (58%) outnumbered nosocomial cases, with a 2:1 ratio.
- No significant risk factors distinguished community MRSA from MSSA; multiple distinct MRSA strains were identified in both community and hospital settings.
Conclusions:
- MRSA is frequently present on hospital admission, suggesting community acquisition.
- Diverse MRSA strains circulate in the community and hospital, highlighting the need for targeted surveillance and control strategies.
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