Socioeconomic Risk Factors for Incomplete Vaccination in Swedish Two-Year-Olds—A Nationwide, Population-Based Cohort Study

Abstract

Aim: To analyse the association between specific socioeconomic measures and the risk of incomplete vaccination for diphtheria-tetanus-pertussis (DTP) and measles-containing vaccine (MCV) in Swedish two-year-olds. Methods: This nationwide, population-based cohort study included 227 457 children born in Sweden during 2014–2015. Data were obtained from the National Vaccination Register (NVR) and linked to socioeconomic data from Statistics Sweden. Multivariable logistic regression was used to estimate the associations between family characteristics—including income, education, employment, and family structure—and incomplete DTP and MCV vaccination at 24 months of age. Results: Incomplete vaccination was found in 13.1% of children for DTP3 (three doses) and 8.7% for MCV1 (one dose). Low family income, single parenthood, parental unemployment, frequent residential mobility, and parental immigration were risk factors for incomplete vaccination. A previously unreported risk factor was having a sibling with a disability or chronic disease, which increased the risk of incomplete DTP3 (aOR 1.15, 95% CI 1.05–1.27) and MCV1 (aOR 1.27, 95% CI 1.14–1.41). Conclusion: Despite a tax-funded national immunisation programme, socioeconomic disparities in vaccination coverage exist in Sweden. Children in socially vulnerable families, and those with siblings requiring disability support, need targeted interventions to ensure full immunisation.