title: Population-based laboratory surveillance of Hafnia alvei isolates in a large Canadian health region.
abstract: BACKGROUND
  Hospital-based series have characterized Hafnia alvei primarily as an infrequent agent of polymicrobial nosocomial infections in males with underlying illness.
  
  
  METHODS
  We conducted population-based laboratory surveillance in the Calgary Health Region during 2000-2005 to define the incidence, demographic risk factors for acquisition, and anti-microbial susceptibilities of Hafnia alvei isolates.
  
  
  RESULTS
  A total of 138 patients with Hafnia alvei isolates were identified (2.1/100,000/year) and two-thirds were of community onset. Older age and female gender were important risk factors for acquisition. The most common focus of isolation was urine in 112 (81%), followed by lower respiratory tract in 10 (7%), and soft tissue in 5 (4%), and the majority (94; 68%) were mono-microbial. Most isolates were resistant to ampicillin (111;80%), cephalothin (106; 77%), amoxicillin/clavulanate (98; 71%), and cefazolin (95; 69%) but none to imipenem or ciprofloxacin.
  
  
  CONCLUSIONS
  Hafnia alvei was most commonly isolated as a mono-microbial etiology from the urinary tract in women from the community. This study highlights the importance of population-based studies in accurately defining the epidemiology of an infectious disease.
authors.affiliation: Department of Medicine, University of Calgary and Calgary Health Region, Calgary Alberta, Canada. kevin.laupland@calgaryhealthregion.ca
authors.forename: Kevin B
authors.initials: KB
authors.lastname: Laupland
authors.forename: Deirdre L
authors.initials: DL
authors.lastname: Church
authors.forename: Terry
authors.initials: T
authors.lastname: Ross
authors.forename: Johann D D
authors.initials: JD
authors.lastname: Pitout
mesh_terms: D017677:Age Distribution; D000367:Age Factors; D000368:Aged; D000416:Alberta / Q000453:epidemiology; D004756:Enterobacteriaceae Infections / Q000453:epidemiology*; D005260:Female; D020611:Hafnia alvei / Q000302:isolation & purification; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D012307:Risk Factors