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Evolving Epidemiology of Staphylococcus aureus Bacteremia
Yoona Rhee1, Alla Aroutcheva1, Bala Hota1
11Division of Infectious Diseases,Department of Medicine,Rush University Medical Center,Chicago,Illinois.
Infection Control and Hospital Epidemiology
|September 16, 2015
Summary
Methicillin-resistant Staphylococcus aureus (MRSA) USA300 strains are common in hospitals and communities. Drug use is a key risk factor for USA300 MRSA bloodstream infections (BSIs), suggesting targeted prevention is needed.
Area of Science:
- Infectious Diseases
- Epidemiology
- Microbiology
Background:
- Methicillin-resistant Staphylococcus aureus (MRSA) USA300 strains are prevalent in community and healthcare settings.
- Understanding risk factors for Staphylococcus aureus bloodstream infections (BSIs) across different strain types is crucial.
Purpose of the Study:
- To investigate the epidemiology of Staphylococcus aureus BSIs.
- To differentiate between USA300 and non-USA300 MRSA strains in BSIs.
Main Methods:
- Retrospective observational study analyzing electronic surveillance data from a large urban hospital (2007-2013).
- Molecular analysis of MRSA isolates using pulsed-field gel electrophoresis.
- Multivariate logistic regression to identify risk factors for BSIs.
Main Results:
- 1,015 S. aureus BSIs identified; 36% were MRSA.
- Hospital-onset MRSA BSIs decreased, while community-onset MRSA BSIs remained stable.
- USA300 was the predominant MRSA strain in hospital-onset BSIs; drug use was the primary risk factor for USA300 BSIs.
Conclusions:
- USA300 MRSA is endemic in both community and hospital environments.
- Enhanced community prevention strategies targeting populations with a history of drug use are recommended.
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