title: A portrait of the geographic dissemination of the Clostridium difficile North American pulsed-field type 1 strain and the epidemiology of C. difficile-associated disease in Québec.
abstract: BACKGROUND
  An increase in the incidence and severity of Clostridium difficile-associated disease in Québec and the United States has been associated with a hypervirulent strain referred to as North American pulsed-field type 1 (NAP1)/027.
  
  
  METHODS
  In 2005, a prospective study was conducted in 88 Québec hospitals, and 478 consecutive nosocomial isolates of C. difficile were obtained. The isolates were subjected to pulsed-field gel electrophoresis (PFGE) typing, antimicrobial susceptibility testing, and detection of binary toxin genes and tcdC gene deletion. Data on patient age and occurrence of complications were collected.
  
  
  RESULTS
  PFGE typing of 478 isolates of C. difficile yielded 61 PFGE profiles. Pulsovars A (57%), B (10%), and B1 (8%) were predominant. The PFGE profile of pulsovar A was identical to that of strain NAP1. It showed 67% relatedness with 15 other PFGE patterns, among which 11 had both binary toxin genes and a partial tcdC deletion but different antibiotic susceptibility profiles. Pulsovars B and B1 were identical to strain NAP2/ribotype 001. In hospitals showing a predominant clonal A or B-B1 PFGE pattern, incidence of C. difficile-associated disease was 2 and 1.3 times higher, respectively, than in hospitals without any predominant clonal PFGE pattern. Severe disease was twice as frequent among patients with strains possessing binary toxin genes and tcdC deletion than among patients with strains lacking these virulence factors.
  
  
  CONCLUSIONS
  This study helped to quantify the impact of strain NAP1 on the incidence and severity of C. difficile-associated disease in Québec in 2005. The identification of the geographic dissemination of this predominant strain may help to focus regional infection-control efforts.
authors.affiliation: Institut National de Santé Publique du Québec, Québec, Canada. bruno.hubert@chu-bordeaux.fr
authors.forename: Bruno
authors.initials: B
authors.lastname: Hubert
authors.forename: Vivian G
authors.initials: VG
authors.lastname: Loo
authors.forename: Anne-Marie
authors.initials: AM
authors.lastname: Bourgault
authors.forename: Louise
authors.initials: L
authors.lastname: Poirier
authors.forename: André
authors.initials: A
authors.lastname: Dascal
authors.forename: Elise
authors.initials: E
authors.lastname: Fortin
authors.forename: Marc
authors.initials: M
authors.lastname: Dionne
authors.forename: Manon
authors.initials: M
authors.lastname: Lorange
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D016360:Clostridioides difficile / Q000145:classification* / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification; D003015:Clostridium Infections / Q000453:epidemiology* / Q000382:microbiology*; D005838:Genotype; D015994:Incidence; D008826:Microbial Sensitivity Tests; D011792:Quebec / Q000453:epidemiology
chemical_list: D000900:Anti-Bacterial Agents