Drivers of human papillomavirus vaccine uptake in migrant populations and interventions to improve coverage: a systematic review and meta-analysis.

Background: WHO's Cervical Cancer Elimination Initiative has set a target for 90% of girls to be fully vaccinated against human papillomavirus (HPV) by the age of 15 years by 2030, to substantially reduce deaths from cervical and other HPV-related cancers. However, progress has been slow, with only 27% global vaccine coverage in 2023. Migrants are an under-immunised group globally for many vaccine-preventable diseases, with data showing that they experience a high burden of HPV infection and widespread HPV under-immunisation. We aimed to identify drivers of HPV vaccine uptake in migrants, as well as assess uptake and explore recommended approaches, strategies, and best practices to promote uptake in migrant communities.

Methods: In this systematic review and meta-analysis, we searched seven databases and several grey literature sources for information published in any language between Jan 1, 2006, and Dec 4, 2024, on the drivers of HPV vaccine uptake among migrants globally. Defining migrants as foreign-born nationals, we included qualitative and quantitative cross-sectional studies, cohort studies, and randomised controlled trials focused on first-generation and second-generation migrants and excluded studies of internal migrants. Outcomes were frequency and percentage of HPV vaccine uptake; factors positively or negatively influencing uptake; and recommended approaches, strategies, and best practices to promote uptake as reported by study authors or participants. We conducted a hybrid thematic analysis using the WHO Behavioural and Social Drivers of Vaccination model to map drivers of uptake, and a random-effects meta-analysis to calculate pooled estimates of uptake. Risk of bias was assessed using Joanna Briggs Institute checklists. This study is registered with PROSPERO, CRD42022347513.

Findings: Of 3562 records returned by the search, 117 studies were included in the analysis, involving 5 638 838 participants across 16 countries and one territory, of whom 933 189 were first-generation and second-generation migrants. The pooled estimates of HPV vaccine uptake were 23·0% (95% CI 10·0-44·0; I=99·3%; n=7614) among female migrants, 21·0% (5·0-58·0; I=99·3%; n=2764) among male migrants, and 17·0% (8·0-33·0; I=98·0%; n=3583) among male and female migrants combined. 79 (68%) studies were considered at low risk of bias, 32 (27%) were considered at moderate risk, and six (5%) were considered at high risk. Factors negatively influencing vaccine uptake included concerns about vaccine safety, cultural beliefs, uncertainty and low levels of knowledge about HPV vaccines or infection, exposure to negative information, and lack of recommendations from health-care providers. Practical barriers to uptake included little information on services, language barriers, logistical challenges, and the high cost of the vaccine. Enablers mainly included positive perceptions and trust in the vaccine and health-care providers, realistic expectations from parents regarding adolescents' sexual activity, a sense of responsibility, recommendations from health-care providers, and support from social networks. Recommended strategies and interventions to improve uptake included culturally sensitive messaging and tailored communication for different target groups (eg, parents or caregivers and adolescents). Deploying trusted mediators (eg, peer school health promoters, religious champions, and community health workers) was key, alongside implementing practical solutions to address missed opportunities (eg, bundling HPV vaccination with other services), implementing eHealth initiatives, ensuring strong provider recommendations, reducing access barriers (eg, through walk-in, mobile, and outreach services), and strengthening vaccination monitoring systems.

Interpretation: We show that migrants globally face complex individual, family and social, and provider-level and system-level barriers to HPV vaccination, resulting in low uptake of HPV vaccines and missed opportunities for protection. In many low-income and middle-income countries, there is little to no availability of vaccines and/or the recipient must pay for them. Achieving global commitments to universal and equitable immunisation across the life course-and making progress towards cervical cancer elimination-requires these barriers to be addressed through multipronged strategies. Collaborative efforts with migrant communities are essential to co-develop effective, tailored delivery models that meet their unique needs.

Funding: The National Institute for Health and Care Research, the Academy of Medical Sciences, and the Medical Research Council.