Department of Social and Preventive Medicine, Laval University and Quebec National Public Health Institute, Quebec, Canada. philippe.dewals@msp.ulaval.ca
Source
Pediatr Infect Dis J. 2004 Dec;23(12 Suppl):S280-4
Several outbreaks caused by virulent strains of serogroup C Neisseria meningitidis were observed in several Canadian provinces in the early 1990s. In an attempt to control these outbreaks, local immunization programs, with polysaccharide vaccines, directed at school age children and adolescents were initiated. In Quebec, however, the incidence of serogroup C meningococcal disease remained high among unvaccinated groups, and clusters appeared in previously unaffected areas. As a result, a 1-dose immunization campaign was initiated, targeting all 1.9 million people between 6 months and 20 years of age for vaccination with the polysaccharide vaccine. This campaign was effective in controlling the epidemic, but there was no evidence of vaccine effectiveness among children