Abstract
Background
In 2002–2003, as part of a pilot project, varicella vaccination was offered to susceptible students in grades 4 and 5 in schools whose health services are provided by a local community services centre in Montréal. This immunization campaign was merged with the hepatitis B immunization programme.
Objectives
To calculate the proportion of grade 4 and 5 students susceptible to varicella; to calculate the proportion of susceptible students who agree to be vaccinated; to compare the proportion of susceptibles who agree to be vaccinated when varicella vaccination is offered with the first or the second dose of hepatitis B; and to assess whether a catch-up varicella immunization programme would affect the vaccine coverage of a concurrent hepatitis B vaccination programme.
Methods
The proportions of susceptible students and of parents of susceptibles who consented to vaccination were calculated. The proportions of parents of susceptibles who consented to vaccination were compared for both immunization strategies: varicella vaccination given with the first or second dose of hepatitis B vaccine. Logistic regression was performed to identify possible associations between consent to varicella vaccination and the various variables collected. Rates of vaccine coverage against hepatitis B after two doses were compared for the years 2000–2001 and 2002–2003.
Results
Of 3,856 registered students, 3,486 (90.4%) returned consent forms. Among the 3,272 students for whom information was available, 441 (13.5%) were susceptible, including 394 (89.3%) who consented to vaccination. The rates of vaccine coverage in the schools after two doses of hepatitis B vaccine were exactly the same for the 2000–2001 and 2002–2003 school years.
Conclusion
Varicella vaccination of susceptible grade 4 and 5 students associated with a coincident hepatitis B vaccination campaign can be performed without negative impact on the hepatitis B vaccination programme.
MeSH terms: Chickenpox, immunization, vaccination, hepatitis B, school
Résmé
Contexte
En 2002–2003, la vaccination contre la varicelle a été offerte aux élèves susceptibles de 4e et de 5e année des écoles situées sur le territoire d’un centre local de services communautaires de Montréal. Cette campagne de vaccination était intégrée au programme de vaccination contre l’hépatite B.
Objectifs
1) Calculer la proportion d’élèves de 4e et de 5e année sensibles à la varicelle; 2) calculer la proportion d’élèves sensibles qui acceptent d’être vaccinés; 3) comparer la proportion d’élèves sensibles qui acceptent d’être vaccinés en fonction du moment où est offerte la vaccination contre la varicelle; et 4) évaluer l’effet d’une campagne de rattrapage pour la varicelle sur le taux de couverture vaccinale du programme régulier de vaccination contre l’hépatite B.
Méthode
La proportion d’enfants sensibles et la proportion de parents d’enfants sensibles qui ont consenti à la vaccination ont été calculées. Les proportions de parents d’élèves sensibles ayant consenti à la vaccination ont été comparées en fonction des deux stratégies de vaccination: l’administration du vaccin contre la varicelle soit avec la première, soit avec la seconde dose du vaccin contre l’hépatite B. Par régression logistique, nous avons cerné les associations possibles entre le consentement à la vaccination contre la varicelle et les différentes variables recueillies. Le taux de couverture vaccinale contre l’hépatite B après deux doses a été comparé pour les années 2000–2001 et 2002–2003.
Résultats:
Sur 3 856 élèves inscrits, 3 486 (90,4 %) ont retourné un formulaire de consentement. Parmi les 3 272 élèves pour lesquels l’information était disponible, 441 (13,5 %) étaient sensibles. Parmi eux, 394 (89,3 %) ont consenti à la vaccination. La proportion d’élèves sensibles et la proportion d’élèves sensibles ayant consenti à la vaccination étaient comparables dans les deux groupes d’intervention.
Conclusion
Une vaccination contre la varicelle des élèves sensibles de 4e et de 5e année en association avec la campagne de vaccination contre l’hépatite B peut se faire sans impact négatif sur la campagne de vaccination contre l’hépatite B.
Footnotes
Source of funding: This project was made possible by funding from the ministère de la Santé et des Services sociaux du Québec.
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