Research Open Access
Like 0



Bloodstream infections (BSI) are a public health concern, and infections caused by resistant bacteria further increase the overall BSI burden on healthcare.


To provide a population-based estimate of BSI incidence and relate this to the forthcoming demographic ageing western population change.


We retrieved positive blood cultures taken from patients in the Skåne region, southern Sweden, 2006–2019 from the Clinical Microbiology Department database and estimated incidence rates (IR), stratified by age (0–49, 50–64, 65–79, ≥ 80 years), sex, year, and species and described antimicrobial susceptibility for Enterobacterales.


We identified 944,375 blood culture sets, and 129,274 (13.7%) were positive. After deduplication and removal of contaminants, 54,498 separate BSI episodes remained. In total, 30,003 BSI episodes (55%) occurred in men. The overall IR of BSI was 307/100,000 person-years, with an average annual increase of 3.0%. Persons ≥ 80 years had the highest IR, 1781/100,000 person-years, as well as the largest increase. (27%) and (13%) were the most frequent findings. The proportion of Enterobacterales isolates resistant to fluoroquinolones and third generation cephalosporins increased from 8.4% to 13.6%, and 4.9% to 7.3%, (p for trend < 0.001), with the largest increase in the oldest age group.


We report among the highest BSI IRs to date worldwide, with a higher proportion among elderly persons and males, including resistant isolates. Given expected demographic changes, these results indicate a possible substantial future BSI burden, for which preventive measures are needed.


Article metrics loading...

Loading full text...

Full text loading...



  1. Goto M, Al-Hasan MN. Overall burden of bloodstream infection and nosocomial bloodstream infection in North America and Europe. Clin Microbiol Infect. 2013;19(6):501-9.  https://doi.org/10.1111/1469-0691.12195  PMID: 23473333 
  2. Kontula KSK, Skogberg K, Ollgren J, Järvinen A, Lyytikäinen O. Population-based study of bloodstream infection incidence and mortality rates, Finland, 2004-2018. Emerg Infect Dis. 2021;27(10):2560-9.  https://doi.org/10.3201/eid2710.204826  PMID: 34546161 
  3. Skogberg K, Lyytikäinen O, Ollgren J, Nuorti JP, Ruutu P. Population-based burden of bloodstream infections in Finland. Clin Microbiol Infect. 2012;18(6):E170-6.  https://doi.org/10.1111/j.1469-0691.2012.03845.x  PMID: 22512663 
  4. Søgaard M, Nørgaard M, Dethlefsen C, Schønheyder HC. Temporal changes in the incidence and 30-day mortality associated with bacteremia in hospitalized patients from 1992 through 2006: a population-based cohort study. Clin Infect Dis. 2011;52(1):61-9.  https://doi.org/10.1093/cid/ciq069  PMID: 21148521 
  5. Verway M, Brown KA, Marchand-Austin A, Diong C, Lee S, Langford B, et al. Prevalence and mortality associated with bloodstream organisms: a population-wide retrospective cohort study. J Clin Microbiol. 2022;60(4):e0242921.  https://doi.org/10.1128/jcm.02429-21  PMID: 35254101 
  6. de Kraker ME, Davey PG, Grundmann H, BURDEN study group. Mortality and hospital stay associated with resistant Staphylococcus aureus and Escherichia coli bacteremia: estimating the burden of antibiotic resistance in Europe. PLoS Med. 2011;8(10):e1001104.  https://doi.org/10.1371/journal.pmed.1001104  PMID: 22022233 
  7. United Nations, Department of Economic and Social Affairs, Population Division (UN). World Population Ageing 2019: Highlights. New York: UN; 2019. Available from: https://www.un.org/en/development/desa/population/publications/pdf/ageing/WorldPopulationAgeing2019-Highlights.pdf
  8. Mehl A, Åsvold BO, Lydersen S, Paulsen J, Solligård E, Damås JK, et al. Burden of bloodstream infection in an area of Mid-Norway 2002-2013: a prospective population-based observational study. BMC Infect Dis. 2017;17(1):205.  https://doi.org/10.1186/s12879-017-2291-2  PMID: 28284196 
  9. Nielsen SL, Pedersen C, Jensen TG, Gradel KO, Kolmos HJ, Lassen AT. Decreasing incidence rates of bacteremia: a 9-year population-based study. J Infect. 2014;69(1):51-9.  https://doi.org/10.1016/j.jinf.2014.01.014  PMID: 24576825 
  10. Laupland KB. Defining the epidemiology of bloodstream infections: the ‘gold standard’ of population-based assessment. Epidemiol Infect. 2013;141(10):2149-57.  https://doi.org/10.1017/S0950268812002725  PMID: 23218097 
  11. The European Committee on Antimicrobial Susceptibility Testing (EUCAST). Breakpoint tables for interpretation of MICs and zone diameters. Version 13.0. Växjö: EUCAST. [Accessed: 14 Feb 2023]. Available from: https://www.eucast.org/clinical_breakpoints
  12. International Code of Nomenclature of Prokaryotes. International code of nomenclature of prokaryotes. Int J Syst Evol Microbiol. 2019;69(1A):S1-111.  https://doi.org/10.1099/ijsem.0.000778  PMID: 26596770 
  13. Kahlmeter G, EUCAST Steering Committee. EUCAST proposes to change the definition and usefulness of the susceptibility category ‘Intermediate’. Clin Microbiol Infect. 2017;23(12):894-5.  https://doi.org/10.1016/j.cmi.2017.08.015  PMID: 28842366 
  14. Statistics Sweden. Statistical database. Population by region, marital status, age and sex. [Accessed: 4 October 2021]. Available from: https://www.scb.se/en/finding-statistics/statistics-by-subject-area/population/population-composition/population-statistics/"https://www.statistikdatabasen.scb.se/pxweb/en/ssd/"
  15. European Commission. Eurostat. Revision of the European Standard Population: report of Eurostat's task force: 2013 edition. Publications Office of the European Union; 11 Jul 2013. Available from: https://data.europa.eu/doi/10.2785/11470
  16. Muggeo VM. Estimating regression models with unknown break-points. Stat Med. 2003;22(19):3055-71.  https://doi.org/10.1002/sim.1545  PMID: 12973787 
  17. Clegg LX, Hankey BF, Tiwari R, Feuer EJ, Edwards BK. Estimating average annual per cent change in trend analysis. Stat Med. 2009;28(29):3670-82.  https://doi.org/10.1002/sim.3733  PMID: 19856324 
  18. Laupland KB, Niven DJ, Pasquill K, Parfitt EC, Steele L. Culturing rate and the surveillance of bloodstream infections: a population-based assessment. Clin Microbiol Infect. 2018;24(8):910 e1-e4.
  19. Skogberg K, Lyytikäinen O, Ruutu P, Ollgren J, Nuorti JP. Increase in bloodstream infections in Finland, 1995-2002. Epidemiol Infect. 2008;136(1):108-14.  https://doi.org/10.1017/S0950268807008138  PMID: 17335630 
  20. Uslan DZ, Crane SJ, Steckelberg JM, Cockerill FR 3rd, St Sauver JL, Wilson WR, et al. Age- and sex-associated trends in bloodstream infection: a population-based study in Olmsted County, Minnesota. Arch Intern Med. 2007;167(8):834-9.  https://doi.org/10.1001/archinte.167.8.834  PMID: 17452548 
  21. Douglas NM, Hennessy JN, Currie BJ, Baird RW. Trends in Bacteremia over 2 decades in the top end of the northern territory of Australia. Open Forum Infect Dis. 2020;7(11):ofaa472.  https://doi.org/10.1093/ofid/ofaa472  PMID: 33204758 
  22. Torisson G, Rosenqvist R, Melander O, Resman F. Hospitalisations with infectious disease diagnoses in somatic healthcare between 1998 and 2019: A nationwide, register-based study in Swedish adults. Lancet Reg Health Eur. 2022;16:100343.  https://doi.org/10.1016/j.lanepe.2022.100343  PMID: 35360441 
  23. Laupland KB, Pasquill K, Parfitt EC, Naidu P, Steele L. Burden of community-onset bloodstream infections, Western Interior, British Columbia, Canada. Epidemiol Infect. 2016;144(11):2440-6.  https://doi.org/10.1017/S0950268816000613  PMID: 26996433 
  24. Bonten M, Johnson JR, van den Biggelaar AHJ, Georgalis L, Geurtsen J, de Palacios PI, et al. Epidemiology of Escherichia coli Bacteremia: a systematic literature review. Clin Infect Dis. 2021;72(7):1211-9.  https://doi.org/10.1093/cid/ciaa210  PMID: 32406495 
  25. MacKinnon MC, McEwen SA, Pearl DL, Lyytikäinen O, Jacobsson G, Collignon P, et al. Increasing incidence and antimicrobial resistance in Escherichia coli bloodstream infections: a multinational population-based cohort study. Antimicrob Resist Infect Control. 2021;10(1):131.  https://doi.org/10.1186/s13756-021-00999-4  PMID: 34488891 
  26. Holmbom M, Giske CG, Fredrikson M, Östholm Balkhed Å, Claesson C, Nilsson LE, et al. 14-year survey in a Swedish county reveals a pronounced increase in bloodstream infections (BSI). Comorbidity - an independent risk factor for both BSI and mortality. PLoS One. 2016;11(11):e0166527.  https://doi.org/10.1371/journal.pone.0166527  PMID: 27835663 
  27. Laupland KB, Lyytikäinen O, Søgaard M, Kennedy KJ, Knudsen JD, Ostergaard C, et al. The changing epidemiology of Staphylococcus aureus bloodstream infection: a multinational population-based surveillance study. Clin Microbiol Infect. 2013;19(5):465-71.  https://doi.org/10.1111/j.1469-0691.2012.03903.x  PMID: 22616816 
  28. Meatherall BL, Gregson D, Ross T, Pitout JD, Laupland KB. Incidence, risk factors, and outcomes of Klebsiella pneumoniae bacteremia. Am J Med. 2009;122(9):866-73.  https://doi.org/10.1016/j.amjmed.2009.03.034  PMID: 19699383 
  29. Public Health Agency of Sweden. Vaccination programmes and recommendations. Stockholm: Public Health Agency of Sweden. [Accessed: 1 Feb 2023]. Available from: https://www.folkhalsomyndigheten.se/the-public-health-agency-of-sweden/communicable-disease-control/vaccinations/vaccination-programmes/#children
  30. Holmbom M, Möller V, Nilsson LE, Giske CG, Rashid MU, Fredrikson M, et al. Low incidence of antibiotic-resistant bacteria in south-east Sweden: An epidemiologic study on 9268 cases of bloodstream infection. PLoS One. 2020;15(3):e0230501.  https://doi.org/10.1371/journal.pone.0230501  PMID: 32218575 
  31. Vock I, Aguilar-Bultet L, Egli A, Tamma PD, Tschudin-Sutter S. Infections in patients colonized with extended-spectrum beta-lactamase-producing enterobacterales: a retrospective cohort study. Clin Infect Dis. 2021;72(8):1440-3.  https://doi.org/10.1093/cid/ciaa895  PMID: 32604410 
  32. The National Board of Health and Welfare (Socialstyrelsen). Statistikdatabas för läkemedel [Statistical database, pharmaceuticals]. Stockholm: Socialstyrelsen; 2005. Swedish. Available from: https://sdb.socialstyrelsen.se/if_lak/val_eng.aspx
  33. Livermore DM, Hope R, Reynolds R, Blackburn R, Johnson AP, Woodford N. Declining cephalosporin and fluoroquinolone non-susceptibility among bloodstream Enterobacteriaceae from the UK: links to prescribing change? J Antimicrob Chemother. 2013;68(11):2667-74.  https://doi.org/10.1093/jac/dkt212  PMID: 23766490 

Data & Media loading...

Supplementary data

Submit comment
Comment moderation successfully completed
This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error