Assessing the impact of the COVID-19 pandemic on routine childhood vaccination uptake, the Netherlands, 2016 to 2025.

BACKGROUNDThe Netherlands has experienced a decline in routine childhood vaccination uptake during and after the COVID-19 pandemic, with emerging evidence of reduced parental vaccine confidence.AIMTo evaluate the immediate and long-term impact of the COVID-19 pandemic on first-dose diphtheria-tetanus-pertussis-poliomyelitis (DTaP-IPV) 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 6 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 (ITS). To further assess the independent effects of the pandemic, matched-sibling analysis compared vaccination uptake within families before, during and after the pandemic.RESULTSITS 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: 0.981-0.986) that further declined after its end (OR: 0.995; 95% CI: 0.993-0.998). 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 with their pre-pandemic siblings. Also, later birth order was associated with lower odds compared with 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 childhood vaccination uptake, which may reflect lingering pandemic effects and/or new post-pandemic factors, highlighting the need for further research into the drivers of vaccination uptake changes in the post-pandemic era.