Abstract
Objective: A survey was conducted in the Province of Quebec to document the factors associated with an incomplete immunization status among 2-year-old children.
Methods: Parents of 430 completely and 266 partially vaccinated children selected from the computerized vaccination register agreed to participate.
Results: The non-simultaneous administration of the 2nd MMR and 4th DPT-P-Hib at 18 months of age was responsible for 46% of incompleteness. The following characteristics were significantly associated with an incomplete immunization status: being a single parent, ≥ 2 children in the family, an older age at first immunization (≥ 3 months), parent’s preference for postponing the second vaccine when two injections are scheduled for the same visit, perception of lack of information about vaccination, and disagreement with immunization recommendations.
Conclusion: One of the key points of this study is the impact of the non-simultaneous administration of the two vaccines at 18 months. Factors such as being a single parent and older age at first immunization might be used to design an early intervention for children who are most likely to be incompletely immunized. Even if parents are favourable towards immunization, they need to be well informed about the associated risks and benefits.
Résumé
Objectif: Une enquête postale a été réalisée au Québec pour connaître les facteurs associés à une vaccination incomplète à l’âge de 2 ans.
Méthodes: Les parents de 430 enfants complètement vaccinés et 266 enfants incomplètement vaccinés ont été sélectionnés à partir des registres de vaccination.
Résultats: Le fait de ne pas avoir reçu simultanément le 2e RRO et le 4e DCT-P-Hib prévus à l’âge de 18 mois était responsable de 46 % des incomplétudes au calendrier vaccinal. Les caractéristiques suivantes étaient également associées au statut vaccinal incomplet: la monoparentalité, être dans une famille de 2 enfants ou plus, l’âge au premier vaccin (≥3 mois), la préférence des parents de ne pas faire donner 2 vaccins le même jour, la perception d’un manque d’information et un désaccord avec les recommandations vaccinales.
Conclusion: Le fait saillant de cette étude est l’impact de ne pas administrer le même jour les deux vaccins prévus à 18 mois. La monoparentalité et l’âge tardif au premier vaccin pourraient être utilisées comme marqueurs pour intervenir précocement auprès des enfants plus à risque de ne pas compléter leur calendrier vaccinal. On constate aussi que même si les parents sont généralement favorables à la vaccination, ils ont besoin d’être bien informés sur les avantages et les risques associés.
Footnotes
Remerciements: Les auteurs tiennent tout particulièrement à remercier les parents ayant participé à l’étude ainsi que les personnes ayant collaboré aux différentes étapes du projet, entre autres, Sophie Auger, Claude Boulianne, Ramak Shadmani, Colette Couture, Martine Nadeau, Nathalie Laflamme, Marjolaine Guay et Odette Meunier.
Aide financière et renonciations: Ministère de la santé et des services sociaux du Québec et Directions régionales de la santé publique de Montréal, Québec et Mauricie-Trois-Rivières.
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