Resumen:
Universal access to influenza vaccination in pediatric age is crucial to reducing the burden of influenza among children. This study aimed to assess whether school-based influenza vaccination programs improve access and equity compared to health center-based campaigns, by comparing coverages by parental origin and economic status. We performed an observational, cross-sectional, population-based study in the Region of Murcia, Spain, using data from the regional registry of vaccinations (VACUSAN). Participants were 2018 and 2019-borns vaccinated with live attenuated influenza vaccine (LAIV) during the 2022-2023 health center-based vaccination campaign, and 2019 and 2020-borns vaccinated during the 2023-2024 school-based campaign as well as children born in 2021 before October 9, vaccinated during the 2023-2024 campaign at health centers. The outcome measure was vaccination coverage for each campaign and birth cohort by main parent's origin and economic section. During the 2022-2023 campaign 11,122 3 and 4-year-old children were vaccinated and 16,870 during the 2023-2024 school-based campaign; an additional 4605 2-year-old children were vaccinated at health centers in 2023-2024 campaign. Global coverage rose for 3 and 4-year-olds between campaigns for all main parent's origin and economic sections, with the biggest rise for the Western Mediterranean Origin. Similar results were observed for economic section F003 (foreign children without residence permit). During 2023-2024 campaign, 3 and 4-year-olds, vaccinated at school, achieved higher coverages than 2-year-olds, vaccinated at health centers, with the biggest differences for section 001 (lowest income). School vaccination campaigns achieve higher coverage than health center-based campaigns, particularly among children from disadvantaged socioeconomic groups, thereby promoting equity.