Abstract
Background
Immunization is one of the most successful public health initiatives in Canada, yet continuous monitoring of coverage rates is essential to ensure high uptake for sustained success. The purpose of this study was to utilize newly available data from the Saskatchewan Immunization Management System (SIMS) to examine city and neighbourhood uptake of the Measles, Mumps and Rubella vaccine and identify potential factors that contribute to low immunization uptake in Saskatoon.
Methods
The study examined records for 10,287 two year olds between 1999 and 2002 using an ecological study design. The first step consisted of simple rate calculations to determine the total, complete, up-to-date and not up-to-date immunization rates for the city of Saskatoon and in each residential neighbourhood. Quantitative neighbourhoodlevel data were then used to determine if neighbourhood variables could significantly contribute to the variation in immunization coverage.
Results
The findings revealed MMR/MR immunization rates were relatively stable between 1999 and 2002. However, significant disparities were found at the neighbourhood level, with areas of social and economic disadvantage having lower rates of total, complete, and up-to-date immunization uptake compared to areas of greater social and economic wealth. Multivariate linear regression revealed 80.6% of variation in up-to-date immunization uptake in Saskatoon could be explained by the proportion of single mothers and vehicles per capita in the neighbourhood.
Conclusion
Significant inequities in immunization uptake exist on the neighbourhood level in Saskatoon. These findings are supported by the literature and may indicate the presence of real or perceived barriers to immunization in some Saskatoon neighbourhoods.
MeSH terms: Immunization, measles, mumps, rubella, neighbourhood
Résumé
Contexte
Bien que l’immunisation soit l’une des initiatives les plus réussies dans le domaine de la santé publique au Canada, elle nécessite une surveillance continue de la couverture vaccinale afin de s’assurer que les taux de réception des vaccins demeurent élevés. L’objet de la présente étude était de recourir à des données récentes du Saskatchewan Immunization Management System (SIMS) afin de se pencher sur le taux de réception des vaccins contre la rougeole, les oreillons et la rubéole de la ville de Saskatoon et de ses quartiers, et de cerner les facteurs qui pourraient contribuer à un faible taux de réception des vaccins à Saskatoon.
Méthode
Les données relatives à 10 287 enfants âgés de deux ans, de 1999 à 2002, ont été analysées au moyen d’une étude écologique. La première étape consistait simplement à calculer les taux de couverture vaccinale totale, optimale, à jour et non à jour pour la ville de Saskatoon ainsi que pour chaque quartier résidentiel. Par la suite, les données quantitatives par quartier ont servi à vérifier si des variables relatives aux quartiers pouvaient avoir un effet important sur les variations de la couverture vaccinale.
Résultats
Les taux de vaccination ROR/RR sont demeurés relativement stables de 1999 à 2002. Cependant, des disparités importantes ont été décelées d’un quartier à l’autre: les quartiers désavantagés socialement et économiquement avaient des taux de vaccination plus faibles, relativement à la couverture vaccinale totale, optimale et à jour, que les quartiers plus favorisés socialement et économiquement. L’analyse de régression linéaire multivariée a révélé que 80,6 % des variations de la couverture vaccinale à jour à Saskatoon étaient attribuables à la proportion de mères seules et de véhicules par habitant se rapportant à un quartier donné.
Conclusion
Des inégalités importantes existent pour ce qui est de la couverture vaccinale au niveau des quartiers de Saskatoon. Ces observations sont appuyées par les études antérieures et pourraient signaler la présence de barrières à l’immunisation, réelles ou perçues, dans certains quartiers de Saskatoon.
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