Human papillomavirus (HPV) Vaccination programmes across European countries: time-harmonized coverage among adolescent females, socioeconomic predictors, and impact on public interest

BACKGROUND: Human papillomavirus (HPV) vaccination represents a cornerstone of cervical cancer prevention and is essential to achieving the WHO elimination targets in Europe. The study aimed to assess HPV vaccination coverage trends among adolescent females across Europe, identify key predictors of uptake, and evaluate the association between the introduction of HPV vaccination into National Immunization Programmes (NIPs) and public interest, as reflected by online search activity. METHODS: This country-level longitudinal study analysed available 2010-2023 full-dose HPV vaccination coverage data among 15-year-old females across 43 European countries, by years since introduction within the NIPs. Socioeconomic, institutional, health-system, and delivery indicators were integrated with Google Trends Relative Search Volume for the "HPV vaccine" topic. Multivariable GEE models were used to identify predictors of vaccination coverage, while Pearson correlations assessed the association between Relative Search Volume and coverage. RESULTS: Coverage among adolescent females increased markedly after NIP introduction, with population-weighted coverage reaching about 40% by year 2 and stabilising at 55-60% by year 5. Coverage exceeded 60% in most countries by year 15. Multivariable analyses identified lower public disagreement with vaccine safety and higher physician density as significant determinants, with interactions between time since NIP introduction and HDI. School-based programmes were associated with a faster increase. Among 32 countries with Google Trends data, 53% showed significant Relative Search Volume changes after NIP introduction, and Relative Search Volume strongly correlated with coverage (r = 0.89). CONCLUSIONS: HPV vaccination coverage among adolescent females in Europe remains uneven and below the WHO 90% target. Strengthening public confidence, primary care capacity, school-based delivery, and digital monitoring may help close immunization gaps and accelerate progress toward cervical cancer elimination.