Effect of school-based HPV vaccine campaigns on inequalities in uptake in France: the PrevHPV trial

BACKGROUND: HPV vaccination is recommended in France for all adolescents aged 11-14. Coverage has increased over recent years but remains below 50% by age 15, with social disparities by area deprivation level, parental education and income. We analysed the effect of school-wide campaigns on adolescent vaccine uptake and related disparities. METHODS: PrevHPV is a controlled cluster-randomised trial to assess the effectiveness and efficiency of a multi-component intervention targeting middle schools and general practitioners. Sixty-one French middle schools were randomised in a partial factorial design to one of six intervention arms, some of which included school-based vaccine campaigns combined with in-class education and motivation. We assessed HPV vaccine status using online questionnaires that were administered in class to pupils (aged 13-15 years) at baseline and after 5 months. Using linear regression, we explored the decomposed effect of campaigns on vaccine uptake and interactions of the effect with sociodemographic variables. RESULTS: In total, 2639 adolescents provided complete vaccination data on both questionnaires, with a ≥ 1-dose coverage of 24% at baseline. Among previously unvaccinated pupils (N = 2017), 21% (7%) of girls (boys) in the control group reported receipt of first vaccine dose during the follow-up period, compared to 49% (33%) in arms with vaccine campaigns. Adjusting for baseline vaccine intention, vaccine campaigns increased the 5-month probability of a first dose by 25 (95% confidence interval: 19-31) percentage points compared to the control group. The effect of vaccine campaigns on student-reported vaccine uptake did not substantially vary by school area deprivation level, parental education level, or family multilingualism (compared to French monolingual family). CONCLUSIONS: School-based campaigns substantially increased vaccine coverage among all adolescents within a short time period. Yet, underlying disparities in HPV vaccination were unchanged. KEY MESSAGES: • School-based vaccine campaigns can quickly increase HPV vaccine uptake among adolescents. • Vaccination campaigns need tailored implementation strategies to eventually reduce social disparities in HPV vaccination.