title: The impact of the meningococcal serogroup C conjugate vaccine in Canada between 2002 and 2012.
abstract: BACKGROUND
  Before 2001, the incidence of invasive meningococcal disease (IMD) in Canada was 1.0 per 100 000 per year, with 40% of cases caused by serogroup C organisms. During 2001-2005 all provinces introduced the meningococcal serogroup C conjugate vaccine (MCCV) into their routine infant immunization schedule.
  
  
  METHODS
  Active, prospective, population-based surveillance of IMD in children and adults was conducted by the Canadian Immunization Monitoring Program, ACTive (IMPACT) during 2002-2012. Inclusion criteria were admission to hospital and identification of Neisseria meningitidis from a sterile site. Incidence was estimated using population census data from Statistics Canada.
  
  
  RESULTS
  Prior to MCCV introduction, serogroup C disease incidence was 0.07-0.25 per 100 000 per year depending on the province. Following vaccine introduction, serogroup C disease decreased to <0.05 per 100 000 per year, with a reduction of 14% per year (P = .0014). A decrease occurred in all provinces, despite differing schedules being implemented. The largest decrease of 83% (from 0.27 to 0.05 per 100 000 per year) occurred in the 15-24 year age group (P = .0100) who were not vaccinated in all provinces. There was no impact on the incidence of nonserogroup C disease over the same period (P = .9811).
  
  
  CONCLUSIONS
  MCCV dramatically reduced the incidence of serogroup C IMD in Canada through both direct and indirect effects. The observation that disease incidence decreased with different schedules suggests that the doses at 12 months (common to all provinces) and adolescence (7 of 8 provinces studied) were critical in achieving disease control.
authors: Vaccine Evaluation Center, Division of Infectious and Immunological Diseases, Department of Pediatrics, BC Children's Hospital and the University of British Columbia, Vancouver, Canada Department of Paediatrics, University of Oxford, United Kingdom.
authors: Manish
authors: M
authors: Sadarangani
authors: Vaccine Evaluation Center, Division of Infectious and Immunological Diseases, Department of Pediatrics, BC Children's Hospital and the University of British Columbia, Vancouver, Canada.
authors: David W
authors: DW
authors: Scheifele
authors: Canadian Center for Vaccinology, IWK Health Centre and Dalhousie University, Halifax, Nova Scotia.
authors: Scott A
authors: SA
authors: Halperin
authors: Division of Infectious Diseases, Department of Pediatrics, Stollery Children's Hospital and University of Alberta, Edmonton.
authors: Wendy
authors: W
authors: Vaudry
authors: Division of Infectious Disease, Children's Hospital of Eastern Ontario, Ottawa.
authors: Nicole
authors: N
authors: Le Saux
authors: Vaccine Preventable Bacterial Diseases, National Microbiology Laboratory, Winnipeg, Manitoba, Canada.
authors: Raymond
authors: R
authors: Tsang
authors: Vaccine Evaluation Center, Division of Infectious and Immunological Diseases, Department of Pediatrics, BC Children's Hospital and the University of British Columbia, Vancouver, Canada.
authors: Julie A
authors: JA
authors: Bettinger
mesh_terms: D000328:Adult; D002170:Canada / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D008589:Meningococcal Infections / Q000453:epidemiology* / Q000382:microbiology / Q000401:mortality / Q000517:prevention & control*; D022401:Meningococcal Vaccines / Q000008:administration & dosage / Q000276:immunology*; D038542:Neisseria meningitidis, Serogroup C / Q000276:immunology; D011446:Prospective Studies
chemical_list: D022401:Meningococcal Vaccines; C410218:serogroup C meningococcal conjugate vaccine
keywords: conjugate vaccines; herd immunity; meningitis; meningococcal disease; serogroup C