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Subcutaneous Infection of Methicillin Resistant Staphylococcus Aureus (MRSA)
Published on: February 9, 2011
Community-associated methicillin-resistant Staphylococcus aureus (MRSA) in Australia
Graeme R Nimmo1, Geoffrey W Coombs
1Division of Microbiology, Pathology Queensland Central Laboratory, Herston Hospitals Campus, Herston, Queensland 4029, Australia. Graeme_Nimmo@health.qld.gov.au
International Journal of Antimicrobial Agents
|March 18, 2008
Summary
Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) epidemics have spread across Australia, with diverse clones emerging. PVL-positive strains are linked to severe infections and fatalities, necessitating improved treatment strategies.
Area of Science:
- Microbiology
- Epidemiology
- Infectious Diseases
Background:
- Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) epidemics have been ongoing in Australia since the early 1990s.
- Distinct CA-MRSA clones, differing in Panton-Valentine leukocidin (PVL) production, have predominated in Western Australia and eastern states.
- Epidemic clones have disseminated nationally, with new minor clones emerging, particularly in Western Australia.
Purpose of the Study:
- To document the evolution and characteristics of CA-MRSA epidemics in Australia.
- To analyze the genetic diversity of CA-MRSA clones, including SCCmec types.
- To assess the clinical associations and public health implications of CA-MRSA infections.
Main Methods:
- Epidemiological surveillance of CA-MRSA cases across Australia.
- Molecular typing of CA-MRSA isolates to identify distinct clones.
- Analysis of Panton-Valentine leukocidin (PVL) status and SCCmec types.
- Review of clinical data associated with CA-MRSA infections.
Main Results:
- A total of 45 CA-MRSA clones have been identified in Australia.
- SCCmec types detected include IV (30 clones), V (6 clones), and novel types (9 clones).
- CA-MRSA infections are primarily associated with skin and soft-tissue infections.
- PVL-positive clones are linked to severe conditions like necrotising pneumonia and osteomyelitis, causing fatalities.
- Healthcare-associated acquisition of CA-MRSA is increasing.
Conclusions:
- Australia has experienced a complex evolution of CA-MRSA epidemics with significant clonal diversity.
- PVL-positive CA-MRSA poses a serious threat, particularly to young, healthy individuals, due to severe invasive disease potential.
- Inappropriate initial treatment remains a challenge, and the rise in healthcare-associated infections warrants attention.
- Continued surveillance and development of effective treatment strategies are crucial for managing CA-MRSA in Australia.
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