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Updated: Jun 5, 2026
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Subcutaneous Infection of Methicillin Resistant Staphylococcus Aureus (MRSA)
Published on: February 9, 2011
Methicillin-resistant Staphylococcus aureus colonization at different body sites: a prospective, quantitative
Leonard A Mermel1, Jennifer M Cartony, Pauline Covington
1Department of Medicine, Warren Alpert Medical School of Brown University, Providence, Rhode Island, USA. lmermel@lifespan.org
Journal of Clinical Microbiology
|January 7, 2011
Summary
Quantifying methicillin-resistant Staphylococcus aureus (MRSA) carriage revealed that higher nasal counts increase colonization risk at other body sites. Combining nares and groin samples achieved 98% sensitivity for MRSA detection.
Area of Science:
- Microbiology
- Infectious Diseases
- Epidemiology
Background:
- Methicillin-resistant Staphylococcus aureus (MRSA) poses a significant public health threat.
- Understanding MRSA carriage dynamics is crucial for effective infection control.
Purpose of the Study:
- To quantify MRSA carriage across multiple body sites.
- To determine the correlation between MRSA nasal carriage and colonization at other sites.
- To identify optimal body sites for MRSA screening.
Main Methods:
- Quantitative analysis of MRSA log(10) counts in clinical samples.
- Statistical correlation of MRSA counts between different body sites.
- Sensitivity analysis for MRSA detection using various body site combinations.
Main Results:
- A positive correlation exists between log(10) MRSA counts in nares and other body sites.
- Higher nasal MRSA loads predict increased colonization likelihood at other anatomical locations.
- The combination of nares and groin samples yielded the highest sensitivity (98%) for MRSA detection.
Conclusions:
- Nasal MRSA carriage is a strong indicator of broader body colonization.
- Screening nares and groin provides a highly sensitive method for MRSA detection.
- These findings can inform targeted screening strategies to reduce MRSA transmission.
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