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Healthcare Associated Infections
Methicillin-resistant Staphylococcus Aureus (MRSA) Bacteraemias
For more information about this CEC program, click here

Why is this important?

Healthcare associated infections (HAI) are a leading cause of preventable illness and death [1-5]. Among the pathogens that cause HAI, methicillin-resistant Staphylococcus aureus (MRSA)  causing bacteraemia is a key target for reduction efforts.  MRSA remains a pathogen that continues to cause morbidity and mortality in healthcare settings, particularly among patients in intensive care units [4,6-7]. The epidemiology of MRSA is complex, but the main vehicle of transmission in healthcare settings is likely to be contact transmission between patients, staff and visitors [8].

In Australia, MRSA bacteraemias cause up to 40 per cent of all healthcare-acquired Staphylococcus aureus (S. aureus) bacteraemia [9]. MRSA bacteraemias are associated with increased risk of mortality [10] and contribute a considerable cost to the healthcare system due to the need for prolonged hospital stays, re-admissions and additional diagnostic tests and treatment [11]. National reporting of healthcare acquired S. aureus bacteraemias, including those caused by MRSA, was introduced in Australia in 2008. MRSA bacteraemia incidences and rates also are a key performance indicator for jurisdictions under the National Healthcare Agreement [12]. This section reports 'inpatient' and 'non-inpatient' healthcare-acquired MRSA bacteraemias data.

The HAI Program addresses the Australian Commission on Safety and Quality in Health Care's National Safety and Quality Health Service (NSQHS) Standards [13]:

  1. 3.1 Developing and implementing governance systems for effective infection prevention and control to minimise the risks to patients of healthcare associated infections;
  2. 3.2 Undertaking surveillance of healthcare associated infections initiative;
  3. 3.3 Developing and implementing systems and processes for reporting, investigating and analysing healthcare associated infections, and aligning these systems to the organisation's risk management strategy;
  4. 3.4 Undertaking quality improvement activities to reduce healthcare associated infections through changes to practice.


[1] Klevens RM, Edwards JR, Richards CL et al. Estimating health care-associated infections and deaths in U.S. hospitals,2002. Public Health Rep 2007;122:160-6.
[2] Jarvis WR, Jarvis AA, Chinn RY. National prevalence of methicillin-resistant Staphylococcus aureusin inpatients at US health care facilities, 2010. Am J Infect Control 2012;40:194-200.
[3] Sievert DM, Ricks P, Edwards JR, et al. Antimicrobial-resistant pathogens associated with healthcare-associated infections: summary of data reported to the National Healthcare Safety Networkat the Centers for Disease Control and Prevention, 2009-2010. Infect Control Hosp Epidemiol 2013;34:1-14.
[4] Huang et al. Targeted versus Universal Decolonization to Prevent ICU Infection N Engl J Med 2013;368:2255-65.
[5] Graves N, Weinhold D, Tong E, etal. Effect on healthcare-acquired infection on length of hospital stay and cost. Infect Control Hosp Epidemiol. 2007; 28(3): 280-292.
[6] Fridkin SK: Increasing prevalence of antimicrobial resistance in intensive care units. Crit Care Med 2001, 29(Suppl 4):N64-N68
[7] Archibald L, Phillips L, Monnet D, McGowan JE Jr, Tenover F, Gaynes R: Antimicrobial resistance in isolates from inpatients and outpatients in the United States: increasing importance of the intensive care unit. Clin Infect Dis 1997, 24:211-215.
[8] Bauer TM, Ofner E, Just HM, et al. An epidemiological study assessing the relative importance of airborne and direct contact transmission of microorganisms in the medical intensive care unit. J Hosp Infect. 1990; 15 (4):301-309.
[9] Collignon P, Nimmo GR, Gottlieb T, et al. Staphylococcus aureusbacteremia, Australia. Emerg Infect Dis. 2005; 11(4):554-561.
[10] Cosgrove SE, Sakoulas G, Perencevich EN, et al. Comparison of mortality associated with methicillin-resistant and methicillin-susceptible Staphylococcus aureus bacteremia: a meta-analysis. Clin Infect Dis.2003; 36 (1):53-59.
[11] Engemann JJ, Carmeli Y, Cosgrove SE, et al . Adverse clinical and economic outcomes attributable to methicillin resistance among patients with Staphylococcus aureus surgical site infection. Clin Infect Dis. 2003, 36 (5):592-598.
[12] Standing Council on Federal Financial Relations. National Healthcare Agreement 2012. Accessed 7 November 2013 [Online]:
[13] Australian Commission on Safety and Quality in Health Care (September 2011). National Safety and Quality Health Service Standards, ACSQHC, Sydney
[14] Lowy FD. Staphylococcus aureus infections. N Engl J Med. 1998; 339 (8):520-32.
[15] Grundmann H, Aires-de-Sousa M,Boyce J, et al. Emergence and resurgence of methicillin-resistant Staphylococcus aureus as a public- health threat. Lancet. 2006; 368 (9538):874-85.


The annual rate of MRSA bacteraemias in NSW has declined from 0.36 in 2011 to 0.17 per 10,000 occupied bed days in 2016 (233 and 131 infections recorded respectively) (Chart MR01).


In recent years, rates of MRSA bacteraemias have fallen because of improved hand hygiene, infection prevention and control practices. The prevention of MRSA bacteraemia, however, still remains a priority for NSW Health.

What we don't know

S. aureus is a normal human commensal that can also behave as a versatile and virulent pathogen [14]. Treatment of MRSA bacteraemias is becoming increasingly difficult, because of the growing prevalence of multi-drug resistant strains [15]. Underlying patient factors are important in determining the likelihood of pathogen transmission and complicated bacteraemia and require further investigation beyond the data presented here.

The analysis of infection data by; its origin whether it is hospital- or community-acquired, hospital peer group classification, or a change in severity stages during hospital admission may shed some light on the MRSA transmission process.


[14] Lowy FD. Staphylococcus aureus infections. N Engl J Med 1998; 339:520-32.
[15] Grundmann H, Aires-de-Sousa M, Boyce J, Tiemersma E. Emergence and resurgence of methicillin-resistant Staphylococcus aureus as a public- health threat.Lancet 2006; 368:874-85.

Chart MR01 - Methicillin-resistant Staphylococcus aureus (MRSA) Bacteraemias
MRSA bacteraemia rate per 10,000 occupied bed days (public hospitals), NSW, Jan 2012 - Sep 2017

Source: NSW Ministry of Health, Clinical Excellence Commission

End Matter

Drafted by: CEC eChartbook team and CEC Governance and Assurance Directorate
Data analysis by: CEC eChartbook team
Reviewed by: CEC Governance and Assurance Directorate
Edited by: CEC eChartbook team

Suggested citation
Clinical Excellence Commission (access year). eChartbook Portal: Safety and Quality of Healthcare in New South Wales. Sydney: Clinical Excellence Commission. Available at: Accessed (insert date of access).

© Clinical Excellence Commission 2018
This work is copyright. Apart from any use as permitted under the Copyright Act 1968, no part may be reproduced without prior written permission from the Clinical Excellence Commission (CEC). Requests and enquiries concerning reproduction and rights should be directed to the Director, Information Management, Locked Bag 8, Haymarket NSW 1240.

Evidence-base for this initiative

Reported elsewhere
Healthcare Associated Infection, NSW MOH -


Chart: MR01

Admin Status: Current, Sep 2017

Indicator Name: Methicillin-resistant Staphylococcus aureus (MRSA) bacteraemias

Description: Methicillin-resistant Staphylococcus aureus (MRSA) bacteraemia rate per 10,000 occupied bed days (public hospitals only), NSW, Jan 2012 - Sep 2017

Dimension: Patient safety

Clinical Area: Initiatives in safety and quality health care

Data Inclusions: All methicillin-resistant Staphylococcus aureus (MRSA) bacteraemias (including inpatient & non-inpatient)

Data Exclusions: None

Numerator: Total number of methicillin-resistant Staphylococcus aureus (MRSA) bacteraemias (including inpatient & non-inpatient)

Denominator: Total number of bed days

Standardisation: None (crude bacteraemia rate per 10,000 occupied bed days calculated)

Data Source: NSW Health Healthcare Associated Infections Data Collection Jan 2012 to Sep 2017, NSW Ministry of Health, Clinical Excellence Commission

Comments: MRSA comprises infections recorded in two clinical indicators (Clinical indicator 2.2 Healthcare associated (inpatient) MRSA BSIs per 10,000 occupied bed days and Clinical indicator 2.4 Healthcare associated (non-inpatient) MRSA BSIs per 10,000 occupied bed days).