Methicillin-resistant Staph. aureus (MRSA)
Staphylococcus aureus is carried by approximately 30 per cent of healthy people in their nose and moist and hairy areas of the body. It is a common pathogen known for causing skin and soft tissue infections, e.g. impetigo, folliculitis, cellulitis, and abscesses. In addition, Staph. aureus may cause systemic infections such as septicaemia, osteomyelitis, pneumonia, endocarditis, and meningitis.
Despite vigorous attempts over the last four decades, the eradication of MRSA has not been very successful for the following reasons:
- Continued use of inappropriate and excessive use of broad-spectrum agents, especially cephalosporins and quinolones
- Lack of isolation facilities and lack of surveillance of multidrug-resistant organisms (MDROs)
- Continued failure to adhere to standard infection prevention and control precautions
- Increasing use of indwelling devices.
- Overcrowding of wards with higher concentrations, especially of elderly patients with multiple comorbidities requiring long-term care, and
- Higher throughput of patients and understaffing
Community-associated MRSA (CA-MRSA) has recently emerged as a major pathogen. Infection with CA-MRSA presents most commonly as relatively minor skin and soft tissue infections, but severe diseases, including necrotizing pneumonia, necrotizing fasciitis, osteomyelitis, and sepsis syndrome, have also been reported both in children and adults.
Strains of Staph. aureus (sensitive and methicillin-resistant strain) produces several toxins, most notably Panton-Valentine leukocidin (PVL). PVL causes leukocyte destruction and tissue necrosis. For more information and the management of PVL, please refer to the HPA (2008) and PHE (2013) guidance.
References and further reading
- Joint Healthcare Infection Society (HIS) and Infection Prevention Society (IPS) guidelines for the prevention and control of methicillin-resistant Staphylococcus aureus (MRSA) in healthcare facilities. Journal of Hospital Infection, 2021;118: S1-S39. https://www.journalofhospitalinfection.com/action/showPdf?pii=S0195-6701%2821%2900360-1
- Treatment of methicillin-resistant Staphylococcus aureus (MRSA): updated guidelines from the UK. J Antimicrob Chemother. 2021;76(6):1377-1378.
https://academic.oup.com/jac/article/76/6/1377/6134889
- Guidance on the diagnosis and management of PVL-associated Staphylococcus aureus infections (PVL-SA) in England 2008. London: Health Protection Agency, 2008.
- Assessment of risk to close contact of patients with lower respiratory tract infection due to Panton-Valentine leukocidin-positive Staphylococcus aureus in England Enhanced case and household contact protocol Version 1.3. London: Public Health England, 2013.