title: The epidemiology of chickenpox in UK 5-year olds: an analysis to inform vaccine policy.
abstract: Varicella vaccine is not routinely administered to children in many countries including the UK. Longitudinal data are lacking to inform optimal schedules. We report the prevalence of VZV infection at 5 years of age, cumulative incidence between 3 and 5 years and socio-demographic associations with risk of infection using longitudinal data on 12,509 children from the UK Millennium Cohort Study. VZV prevalence by 5 years was 76.9% [95% CI: 75.9%, 78.0%]. The cumulative incidence between 3 and 5 years was 32.2% [95% CI: 31.1%, 33.3%]. Risk of infection by 5 years was associated with higher maternal socio-economic status, larger household size and formal day-care attendance at 9 months and 3 years. If universal varicella immunisation were introduced in the UK, where 40% children have attended some formal day-care by 3 years, a schedule commencing early in the second year of life would be indicated.
authors.affiliation: MRC Centre of Epidemiology for Child Health, UCL Institute of Child Health, 30 Guilford Street, London WC1N 1EH, United Kingdom. g.manikkavasagan@ich.ucl.ac.uk
authors.forename: Gayatri
authors.initials: G
authors.lastname: Manikkavasagan
authors.forename: Carol
authors.initials: C
authors.lastname: Dezateux
authors.forename: Angie
authors.initials: A
authors.lastname: Wade
authors.forename: Helen
authors.initials: H
authors.lastname: Bedford
mesh_terms: D002644:Chickenpox / Q000453:epidemiology*; D002656:Child Day Care Centers; D002675:Child, Preschool; D005006:Ethnicity; D005260:Female; D006291:Health Policy; D014645:Herpesvirus 3, Human; D006801:Humans; D017589:Immunization Programs; D008137:Longitudinal Studies; D008297:Male; D015995:Prevalence; D012307:Risk Factors; D012959:Socioeconomic Factors; D006113:United Kingdom / Q000453:epidemiology