Introduction: Influenza vaccination campaigns have difficulty in reaching the 75% uptake in healthcare workers (HCWs) that public health organizations target. This study runs a campaign across 42 primary care centers (PCCs) where for every HCW vaccinated against influenza, a polio vaccine is donated through UNICEF for children in developing nations. It also analyses the efficacy and cost of the campaign. Method: This observational prospective non-randomized cohort study was conducted across 262 PCCs and 15.812 HCWs. A total of 42 PCCs were delivered the full campaign, 114 were used as the control group, and 106 were excluded. The vaccine uptake in HCWs within each of those PCCs was registered. The cost analysis assumes that campaign costs remain stable year to year, and the only added cost would be the polio vaccines (0.59€). Results: We found statistically significant differences between both groups. A total of 1423 (59.02%) HCWs got vaccinated in the intervention group and 3768 (55.76%) in the control group OR 1.14, CI 95% (1.04–1.26). In this scenario, each additional HCW vaccinated in the intervention group costs 10.67€. Assuming all 262 PCCs had joined the campaign and reached 59.02% uptake, the cost of running this incentive would have been 5506€. The potential cost of increasing uptake in HCWs by 1% across all PCC (n = 8816) would be 1683€, and across all healthcare providers, 8862€ (n = 83.226). Conclusions: This study reveals that influenza vaccination uptake can be innovative by including solidary incentives and be successful in increasing uptake in HCWs. The cost of running a campaign such as this one is low.

Background: Invasive meningococcal disease (IMD) caused by Neisseria meningitidis remains a major public health concern due to its severity, lethality, and long-term sequelae. To address the rise in serogroups W and Y in Spain, the Community of Madrid implemented a catch-up campaign in 2019–2021, targeting adolescents (ages 13–18) alongside routine tetravalent meningococcus vaccine (MenACWY) at age 12. This study evaluated MenACWY catch-up vaccination uptake in routine practice by describing vaccine coverage, temporal trends, and associated factors in adolescents born between 2001 and 2006. Methods: A population-based cross-sectional study was conducted using data from the Community of Madrid’s vaccination registry (SISPAL Vacunas). Vaccination coverage was calculated for adolescents with at least one recorded MenACWY dose from age 10 onwards. Temporal trends were analyzed by birth cohort and calendar time, and multivariable logistic regression models were used to identify factors associated with vaccination uptake. Results: Among 424,059 adolescents, overall vaccination coverage by December 2021 was 63.8%, ranging from 54.4% to 78.2% across birth cohorts. Coverage was highest in the 2006 cohort, likely due to co-administration with the tetanus and diphtheria (Td) booster. A slightly higher uptake was observed among females and adolescents with chronic conditions, while foreign-born adolescents consistently showed lower coverage. COVID-19 disruptions led to temporal variability, with sharp declines during lockdowns and partial recoveries thereafter, with persistent sociodemographic differences in uptake. Conclusions: By December 2021, coverage was incomplete, with marked variability across birth cohorts. Higher uptake was observed when vaccination was integrated into routine visits, while persistent sociodemographic disparities remained evident. These observational findings are consistent with the programmatic value of combined catch-up and routine strategies and the need for targeted actions to ensure equitable MenACWY coverage.