Assessing the impact of the COVID-19 pandemic on routine childhood vaccination uptake in the Netherlands

BackgroundInitial reports from the Netherlands indicate a decline in routine childhood vaccination uptake during and after the COVID-19 pandemic, with emerging evidence of reduced parental vaccine confidence. This study aimed to evaluate the long-term impact of the COVID-19 pandemic on routine childhood vaccination uptake. MethodsWe conducted a retrospective nationwide cohort study including all children born in the Netherlands in 2016-2024. First-dose DTaP-IPV vaccination status by age six months was obtained from the national immunisation register. National trends in vaccination uptake across pre-pandemic, pandemic, and post-pandemic periods were assessed using interrupted time series analyses. To further assess the independent effect of the pandemic, a matched-sibling analysis compared vaccination uptake within families before, during and after the pandemic. ResultsInterrupted time series analyses showed significant immediate decreases in vaccination uptake both at the start and end of the pandemic, accompanied by a continuing downward trend during the pandemic (OR 0.984, 95%CI 0.982-0.985) that further declined after its end (OR 0.995, 95%CI 0.994-0.997). In the matched-sibling analysis children eligible during and after the pandemic had lower odds of being vaccinated (pandemic: OR 0.66, 95%CI 0.55-0.80; post-pandemic: OR 0.20, 95%CI 0.17-0.25) compared to their pre-pandemic siblings. Also, later birth order was associated with lower odds compared to first-born siblings (second-born: OR 0.42, 95%CI 0.37-0.48). ConclusionsBoth analyses indicate a negative impact of the COVID-19 pandemic on parental vaccination decisions, which may reflect lingering pandemic effects or new post-pandemic factors, highlighting the need for further research into the drivers of vaccination uptake changes in the post-pandemic era.