FIG 1.

Diagnostic hierarchy from positive blood cultures to community-onset bloodstream infection. BSI, bloodstream infection; HO, hospital onset; HCA, health care associated; CA, community associated. The overall triangular area indicates all positive blood cultures, which may represent contamination (first level), transient bacteremia/fungemia (second level), or “true” BSI (third level). Bloodstream infections are further classified into the three mutually exclusive categories of hospital-associated, health care-associated community-onset, and community-associated community-onset BSIs.