Social Inequality in the Uptake of Varicella Vaccination: A Danish Nationwide Observational Study.

AIM: Varicella is a highly contagious disease affecting approximately 90% of children before the age of 10, constituting a substantial health and societal burden. This study investigates the association between socio-demographic and socio-economic factors and uptake of varicella vaccination in Denmark, 2019-2024.

METHODS

This Danish cohort study included 1 356 841 individuals aged 1-18 years. Socio-demographic and socio-economic factors for children and their parents were obtained from Statistics Denmark's registers and linked to varicella vaccination status in the Danish Vaccination Register. We estimated yearly vaccination initiation and cumulative vaccine coverage. Associations were assessed using crude and adjusted multivariable logistic regression models.

RESULTS

As of 2024, 16 903 1-18 year olds had received at least one dose of the varicella vaccine, of whom 84% completed the series. Coverage increased markedly from 2019 to 2024 and was highest in the Capital Region and metropolitan municipalities. Vaccination was more likely among children of parents with higher education (aOR: 4.98, 95% CI: 4.05-6.12), higher income (aOR: 3.08, 95% CI: 2.85-3.33) and a background in medicine or nursing (aOR: 1.79, 95% CI: 1.72-1.88).

CONCLUSION

Varicella vaccination uptake is higher among children from families with high socio-economic status, and this pattern persists over a 6-year period.