The decrease in childhood vaccination coverage and its sociodemographic determinants, the Netherlands, birth cohorts 2008 to 2020

Abstract

Background: Childhood vaccination coverage has declined in recent years in many countries, including the Netherlands. Aim: To understand differences in coverage between population subgroups in the Netherlands over time, we studied sociodemographic factors associated with measles–mumps–rubella (MMR) and diphtheria–teta-nus–pertussis–poliomyelitis (DTaP-IPV) vaccination. Methods: We conducted a national retrospective data-base study including children born between 2008 and 2020. Individual-level data linkage allowed examina-tion of associations of sociodemographic variables with MMR and DTaP-IPV vaccination status at age 2 years. We calculated coverage for each variable, strati-fied by birth cohort. Multivariable Poisson regression assessed independent associations and changes in coverage over time. Results: MMR coverage decreased in all population subgroups (overall 95% in cohort 2008 and 89% in cohort 2020), more substantially in some. In multi-variable analysis, children of non-Dutch origin, par-ticularly Moroccan and Turkish origin, showed more pronounced declines (respectively −25% and −12% as children of Dutch origin in cohort 2020). Among children not attending daycare and children living in larger families (≥ 4 children), coverage declined faster than in those attending daycare and living in smaller families (both −12% in cohort 2020). Coverage among children of self-employed mothers and children in the lowest income households was lower than among children of mothers in employment and the highest income households (respectively −8% and −7% in cohort 2020). Trends for DTaP-IPV vaccination were nearly identical. Conclusion: Childhood vaccination coverage in the Netherlands declined substantially, with increasing disparities between sociodemographic groups. Vaccination efforts should be prioritised to protect public health equitably.