Epidemiology and outcomes for Staphylococcus aureus bacteraemia in Australian hospitals, 2005–06: Report from the Australian Group on Antimicrobial Resistance

Abstract

The Australian Group on Antimicrobial Resistance studied the epidemiology and outcomes of Staphylococcus aureus bacteraemia in selected Australian hospitals in 2005–06. Seventeen hospital-based laboratories collected basic demographic, susceptibility and patient outcome data on all cases of S. aureus bacteraemia for 5 to 24 months during the study period. There were 1,511 cases of bacteraemia documented, of which 66% occurred in males and 32% originated from vascular access devices. Bacteraemia had a community onset in 60% of cases, although 31% of these were health-care associated. Overall, 57% of episodes were health-care related. Methicillin-resistant Staphylococcus aureus (MRSA) was the responsible pathogen in 24% of instances; of these 53% were of the typical multi-resistant hospital type, and 29% were of the community-associated type. Seven per cent of all staphylococcal bacteraemias were caused by community-associated MRSA strain types, attesting to the growing size of this problem in Australia. Outcomes were available for 51% of cases and in those the all-cause mortality at seven days or discharge (whichever came earlier) was 11.2%. Age was strongly associated with mortality; the rate for patients aged more than 60 years was 18%. Sepsis originating from intravascular access devices had a lower mortality rate of 5%. S. aureus bacteraemia is a common community and hospital infection with a significant mortality. A nationally co-ordinated program documenting the incidence and outcomes of this disease would likely lead to measures designed to reduce the incidence and improve outcomes of this disease. Commun Dis Intell 2007;31:398–403.