, Volume 47, Issue 6, pp 961–971 | Cite as

Epidemiology and Outcome Determinants of Staphylococcus aureus Bacteremia Revisited: A Population-Based Study

  • John C. Lam
  • Daniel B. Gregson
  • Stephen Robinson
  • Ranjani Somayaji
  • John M. Conly
  • Michael D. ParkinsEmail author
Original Paper



Staphylococcus aureus bacteremia (SAB) is associated with significant morbidity and mortality. We sought to re-define the burden, epidemiology and mortality-associated risk factors of SAB in a large Canadian health region.


Residents (> 18 years) experiencing SAB from 2012 to 2014 were assessed. Incidence rates were calculated using civic census results. Factors associated with 30-day mortality were determined through multivariate logistic regression. Incidence and risk factors for SAB were compared to 2000–2006 data.


780 residents experienced 840 episodes of SAB (MRSA; 20%). Incidence rates increased from 23.5 to 32.0 cases/100,000 from 2012 to 2014; [IRR 1.15 (95% CI 1.07–1.23); p < 0.001]. Compared to a decade ago, incidence of SAB has increased [IRR 1.28 (95% CI 1.21–1.36); p < 0.001] despite minimal change in nosocomial SAB. MRSA proportion did not change through the study (p = 0.3), but did increase relative to a decade ago (20.0% vs 11.0%, p < 0.001). Thirty-day mortality rates were 30.6% and 21.3% for MRSA and MSSA, respectively (p = 0.01), similar to rates from 2000 to 2006. Several clinical, demographic, and biochemical factors were independently associated with SAB mortality.


SAB is common within our population resulting in significant mortality. Incidence rates of SAB are increasing in our health region; however, 30-day mortality rates remain stable.


Bacteremia Staphylococcus aureus MRSA Mortality Epidemiology 



This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors

Compliance with ethical standards

Conflict of interest

All authors declare that they do not have any conflict of interest relevant to this manuscript.

Presented in part

Association of Medical Microbiology and Infectious Disease Conference 2018, Vancouver, BC. Abstract SP 44.


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  • John C. Lam
    • 1
  • Daniel B. Gregson
    • 2
  • Stephen Robinson
    • 3
  • Ranjani Somayaji
    • 4
  • John M. Conly
    • 5
  • Michael D. Parkins
    • 4
    Email author
  1. 1.Department of MedicineUniversity of CalgaryCalgaryCanada
  2. 2.Departments of Medicine and Pathology and Laboratory Medicine, Calgary Laboratory Services, Snyder Institute for Chronic DiseaseUniversity of CalgaryCalgaryCanada
  3. 3.Department of MedicineDalhousie UniversityHalifaxCanada
  4. 4.Departments of Medicine and Microbiology, Immunology and Infectious DiseasesSnyder Institute for Chronic Disease, University of CalgaryCalgaryCanada
  5. 5.Departments of Medicine, Microbiology, Immunology and Infectious Diseases, Pathology and Laboratory Medicine, Snyder Institute for Chronic DiseaseUniversity of CalgaryCalgaryCanada

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