Abstract
Objectives
Canada’s progress in establishing a national immunization registry and coordinated immunization schedule across provinces has been slow. The absence of a centralized registry means there are only limited data available on childhood immunization coverage in Canada. The aim of this study was to estimate the completeness and timeliness of immunization for two year-old children in Nova Scotia.
Methods
The study included 8,245 babies born in Nova Scotia during 2006. Immunization data were derived from three sources: Provincial Medical Insurance Physician Billing data, public health records, and self-report by parents. Immunization uptake rates for vaccines included in the Nova Scotia immunization schedule were calculated at ages 12, 18 and 24 months. Logistic regression was used to analyze vaccine uptake in relation to socioeconomic factors. A telephone survey of a sample of parents of study children was completed.
Results
The overall immunization completeness rate was 49% at 12 months, 40% at 18 months and 58% at 24 months of age. Immunization completeness was significantly higher in more socially disadvantaged communities.
Conclusions
Nova Scotia spends many millions of dollars on vaccine purchase and administration, but, as with numerous Canadian jurisdictions, there is no accurate system for monitoring or evaluating the program. The timeliness and completeness of immunization administration to pre-school children in Nova Scotia is inadequate. Further work should elucidate the barriers and enablers to immunization to ensure that public health education targets those most likely to be under-immunized. A provincial vaccination database should be established to monitor and evaluate the system.
Key words: Immunization, program evaluation, child, information systems
Résumé
Objectifs
Le Canada est lent à établir un registre d’immunisation national et un calendrier vaccinal coordonné entre les provinces. En l’absence d’un registre centralisé, nous ne disposons que de données limitées sur la couverture vaccinale des enfants au pays. Nous avons cherché à estimer si, en Nouvelle-Écosse, les enfants de deux ans reçoivent tous leurs vaccins dans les délais prescrits.
Méthode
L’étude a porté sur 8 245 bébés nés en Nouvelle-Écosse en 2006. Les données de vaccination provenaient de trois sources: les données de facturation des médecins à l’assurance-maladie provinciale, les registres de santé publique et les données autodéclarées par les parents. Les taux de recours aux vaccins inclus dans le calendrier vaccinal de la Nouvelle-Écosse ont été calculés à l’âge de 12, 18 et 24 mois. Par régression logistique, nous avons analysé le recours aux vaccins par rapport à des facteurs socioéconomiques. Nous avons mené une enquête téléphonique auprès d’un échantillon de parents des enfants étudiés.
Résultats
Le taux global des bébés ayant reçu tous leurs vaccins était de 49 % à 12 mois, de 40 % à 18 mois et de 58 % à 24 mois. Ce taux était sensiblement plus élevé dans les communautés socialement défavorisées.
Conclusion
La Nouvelle-Écosse dépense des millions de dollars pour l’achat et l’administration des vaccins, mais comme de nombreuses provinces canadiennes, elle n’a pas de système précis de contrôle et d’évaluation du programme. L’administration des vaccins aux enfants d’âge préscolaire en Nouvelle-Écosse a des carences: trop d’enfants ne reçoivent pas tous leurs vaccins dans les délais prescrits. Il faudrait en faire plus pour élucider les éléments qui favorisent et qui nuisent à la vaccination, afin que l’éducation à la santé publique cible les personnes les plus susceptibles d’être sous-immunisées. Il faudrait établir une base de données provinciale sur la vaccination afin de contrôler et d’évaluer le système.
Mots clés: vaccination, évaluation de programme, enfant, systèmes d’information
Footnotes
Acknowledgements: The NSVaCS Study was funded by the Nova Scotia Department of Health Promotion and Protection (now Health and Wellness). We thank Dr. Jeffrey Scott for his support in establishing this study and Dr. David Elliott for his support overseeing the provision of health records data.
Conflict of Interest: None to declare.
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