title: The effectiveness of serogroup C meningococcal vaccine estimated from routine surveillance data.
abstract: Serogroup C meningococcal vaccine effectiveness was estimated from routine surveillance data, based on a comparison of the proportion of vaccine and non-vaccine serogroups in vaccinated and unvaccinated reported cases. Between 1 April 1993 and 31 March 1998, 109 eligible cases were reported. Among the 54 cases caused by serogroup C, 38 had been vaccinated. Among the 55 cases caused by non-vaccine serogroups, 49 had been vaccinated. Vaccine effectiveness was estimated at 71% (95% CI: 21-89%), a value similar to that obtained in the same population by a cohort study. Effectiveness was lower in children immunized before the age of 10. This demonstrates that meningococcal vaccine effectiveness can be estimated from information obtained routinely from cases only, as an alternative to the more expensive cohort or case-control designs.
authors.affiliation: Direction de la Santé publique, Régie régionale de la santé et des services sociaux de Montréal-Centre, Montreal, Que., Canada. privest@santepub-mtl.qc.ca
authors.forename: Paul
authors.initials: P
authors.lastname: Rivest
authors.forename: Robert
authors.initials: R
authors.lastname: Allard
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D006801:Humans; D007223:Infant; D008585:Meningitis, Meningococcal / Q000517:prevention & control*; D022401:Meningococcal Vaccines / Q000592:standards*; D011159:Population Surveillance
chemical_list: D022401:Meningococcal Vaccines; C410218:serogroup C meningococcal conjugate vaccine