Objectives: To identify groups at risk of methicillin-resistant Staphylococcus aureus (MRSA) infection, patterns of antimicrobial resistance, and the proportion of patients with MRSA infections but no history of recent hospitalisation.
Design, setting and participants: Case series of 39 231 patients with S. aureus isolates from specimens processed by the Hunter New England Local Health District (HNELHD) public pathology provider during 2008–2014.
Main outcome measures: Proportion of MRSA infections among people with S. aureus isolates; antimicrobial susceptibility of MRSA isolates; origin of MRSA infections (community- or health care-associated); demographic factors associated with community-associated MRSA infections.
Results: There were 71 736 S. aureus-positive specimens during the study period and MRSA was isolated from 19.3% of first positive specimens. Most patients (56.9%) from whom MRSA was isolated had not been admitted to a public hospital in the past year. Multiple regression identified that patients with community-associated MRSA were more likely to be younger (under 40), Indigenous Australians (odds ratio [OR], 2.6; 95% CI, 2.3–2.8), or a resident of an aged care facility (OR, 4.7; 95% CI, 3.8–5.8). The proportion of MRSA isolates that included the dominant multi-resistant strain (AUS-2/3-like) declined from 29.6% to 3.4% during the study period (P < 0.001), as did the rates of hospital origin MRSA in two of the major hospitals in the region.
Conclusions: The prevalence of MRSA in the HNELHD region decreased during the study period, and was predominantly acquired in the community, particularly by young people, Indigenous Australians, and residents of aged care facilities. While the dominance of the multi-resistant strain decreased, new strategies for controlling infections in the community are needed to reduce the prevalence of non-multi-resistant strains.
- 1. Brennan L, Lilliebridge RA, Cheng AC, et al. Community-associated methicillin-resistant Staphylococcus aureus carriage in hospitalized patients in tropical northern Australia. J Hosp Infect 2013; 83: 205-211.
- 2. Munckhof WJ, Nimmo GR, Schooneveldt JM, et al. Nasal carriage of Staphylococcus aureus, including community-associated methicillin-resistant strains, in Queensland adults. Clin Microbiol Infect 2009; 15: 149-155.
- 3. Coombs G, Daley D. Australian Staphylococcal Sepsis Outcome Program (ASSOP) 2015: final report. Perth: Australian Group on Antimicrobial Resistance, 2016. http://www.agargroup.org/files/July.2016.ASSOP%202015%20Final%20Report%202016%20(1).pdf (accessed Mar 2017).
- 4. Coombs GW, Daley DA, Thin Lee Y, et al. Australian Group on Antimicrobial Resistance Australian Staphylococcus aureus Sepsis Outcome Programme annual report, 2014. Commun Dis Intell Q Rep 2016; 40: E244-E254.
- 5. Nimmo GR, Bergh H, Nakos J, et al. Replacement of healthcare-associated MRSA by community-associated MRSA in Queensland: confirmation by genotyping. J Infect 2013; 67: 439-447.
- 6. Tong SY, Varrone L, Chatfield MD, et al. Progressive increase in community-associated methicillin-resistant Staphylococcus aureus in Indigenous populations in northern Australia from 1993 to 2012. Epidemiol Infect 2015; 143: 1519-1523.
- 7. Daley D, Coombs G, Nimmo G, et al. Staphylococcus aureus programme 2012. Community survey: antimicrobial susceptibility report. Australian Group on Antimicrobial Resistance (AGAR), 2013. http://www.agargroup.org/files/Staphylococcus%20aureus%20Programme%202012%20Susceptibility%20Report.pdf (accessed Mar 2017).
- 8. Centers for Disease Control and Prevention. Methicillin-resistant Staphylococcus aureus, 2011 [Active Bacterial Core surveillance report]. Nov 2012. https://www.cdc.gov/abcs/reports-findings/survreports/mrsa11.pdf (accessed Jan 2017).
- 9. New South Wales Health. Healthstats NSW 2016. http://www.healthstats.nsw.gov.au/Indicator/dem_pop_atsi/dem_pop_atsi_lhn_snap?filter1ValueId=18403&LocationType=Local%20Health%20District&name=Aboriginal%20Health&code=atsi%20dqi (accessed Jan 2017).
- 10. Australian Bureau of Statistics. 1270.0.55.006. Australian Statistical Geography Standard (ASGS): correspondences, July 2011. June 2012. http://www.abs.gov.au/AUSSTATS/abs@.nsf/Lookup/1270.0.55.006Main+Features1July%202011?OpenDocument (accessed June 2015).
- 11. Clinical and Laboratory Standards Institute. Analysis and presentation of cumulative antimicrobial susceptibility test data: approved guideline (CLSI document M39-A4). 4th edition. Wayne (PA): CLSI, 2014.
- 12. Grayson ML, Russo PL, Cruickshank M, et al. Outcomes from the first 2 years of the Australian National Hand Hygiene Initiative. Med J Aust 2011; 195: 615-619. <MJA full text>
- 13. Lawes T, Lopez-Lozano JM, Nebot CA, et al. Effects of national antibiotic stewardship and infection control strategies on hospital-associated and community-associated meticillin-resistant Staphylococcus aureus infections across a region of Scotland: a non-linear time-series study. Lancet Infect Dis 2015; 15: 1438-1449.
- 14. World Health Organization. Antimicrobial resistance global report on surveillance. Geneva: WHO, 2014. http://www.who.int/drugresistance/documents/surveillancereport/en/ (accessed Mar 2017).
- 15. Australian Government Department of Health, Department of Agriculture. Responding to the threat of antimicrobial resistance. Australia’s first national antimicrobial resistance strategy 2015–2019. Canberra: Department of Health, Department of Agriculture, 2015. http://www.health.gov.au/internet/main/publishing.nsf/Content/1803C433C71415CACA257C8400121B1F/$File/amr-strategy-2015-2019.pdf (accessed Mar 2017).
- 16. Duguid M, Cruickshank M (editors). Antimicrobial stewardship in Australian hospitals. Sydney: Australian Commission on Safety and Quality in Health Care, 2011. https://www.safetyandquality.gov.au/wp-content/uploads/2011/01/Antimicrobial-stewardship-in-Australian-Hospitals-2011.pdf (accessed Mar 2017).
- 17. Turnidge J, Baggoley C, Schipp M, Martin R. Resistance sans frontières: containing antimicrobial resistance nationally and globally. Med J Aust 2016; 204: 207-208. <MJA full text>
- 18. Munckhof WJ, Nimmo GR, Carney J, et al. Methicillin-susceptible, non-multiresistant methicillin-resistant and multiresistant methicillin-resistant Staphylococcus aureus infections: a clinical, epidemiological and microbiological comparative study. Eur J Clin Microbiol Infect Dis 2008; 27: 355-364.
- 19. Jeremiah CJ, Kandiah JP, Spelman DW, et al. Differing epidemiology of two major healthcare-associated meticillin-resistant Staphylococcus aureus clones. J Hosp Infect 2016; 92: 183-190.
- 20. Antibiotic Reference Group. Therapeutic guidelines: antibiotic, version 15. Melbourne: Therapeutic Guidelines Limited, 2014. https://tgldcdp.tg.org.au/guideLine?guidelinePage=Antibiotic&frompage=etgcomplete (accessed Mar 2017).
- 21. Bowen AC, Tong SY, Andrews RM, et al. Short-course oral co-trimoxazole versus intramuscular benzathine benzylpenicillin for impetigo in a highly endemic region: an open-label, randomised, controlled, non-inferiority trial. Lancet 2014; 384: 2132-2140.
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