Field Epidemiology Manual Wiki

Bloodstream Infection

Last modified at 4/26/2016 7:05 AM by Vladimir Prikazsky

The “Point prevalence survey of healthcare associated infections and antimicrobial use in European acute care hospitals” protocol adopts the following definition of Bloodstream Infection (BSI).

Laboratory-confirmed bloodstream infection (BSI):

  • one positive blood culture for a recognised pathogen


  • patient has at least one of the following signs or symptoms: fever (> 38 °C), chills, or hypotension


  • two positive blood cultures for a common skin contaminant (from two separate blood samples, usually within 48 hours).

Skin contaminants are considered: coagulase-negative staphylococci (including S. epidermidis), Micrococcus spp., Propionibacterium acnes, Bacillus spp., Corynebacterium spp.

Sources of bloodstream infection are considered:

  • Catheter-related: the same microorganism was cultured from the catheter or symptoms improve within 48 hours after removal of the catheter (C-PVC: peripheral catheter, C-CVC: central vascular catheter)
  • Secondary to another infection: the same microorganism was isolated from another infection site, or strong clinical evidence exists that bloodstream infection was secondary to another infection site, invasive diagnostic procedure or foreign body:
    • pulmonary (S-PUL);
    • urinary tract infection (S-UTI);
    • digestive tract infection (S-DIG);
    • surgical site infection (S-SSI);
    • skin and soft tissue (S-SST);
    • other (e.g. meningitis, osteomyelitis, etc.) (S-OTH).
  • Unknown origin (UO): none of the above, bloodstream infection of unknown origin (verified during survey and no source found)
  • Unknown (UNK): no information available about the source of the bloodstream infection or information missing



Link to European IC/HH Core Competencies

Area 3. Surveillance and investigation of healthcare associated infection (HAI)


Horan TC, Emori TG. Definitions of keyterms used in the NNIS system. AJIC AM J of Infect Control 1997;25:112-6