Grant: Operating Grant

Infections with meningococcal bacteria are rare but cause serious, fatal illness. Young children ages 0-5 years are at the highest risk for these infections. Prevention is desirable, as about 15% of infected persons die, and another 15% suffer permanent injury. Infection can be prevented with an effective vaccine that is safe for use in infants and children. The best vaccination program would provide protection throughout the peak years of risk (ages 0-5 years). From 2003-2005 Canada started giving meningococcal vaccines to infants. Cost factors limited doses to one dose at 12 months of age in most provinces, except for Alberta, which gives 3 doses and British Columbia (BC), which gives 2 doses. This study will identify and follow 1 year old children over five years to determine which program (1, 2, or 3 doses) and which meningococcal vaccine provides the best protection over the longest period of time. Protection will be assessed by measuring levels of antibody against meningococcal bacteria at several times over the study. The groups will come from Nova Scotia where children receive one dose at 12 months of age; BC where children receive 2 doses at 2 months and 12 months of age; and Alberta where children receive the recommended 3 doses, at 2, 4 and 12 months of age. Our results will provide important knowledge needed to define the best immunization program for young Canadian children.