Defining drivers of human papillomavirus (HPV) vaccine uptake in migrant populations globally and strategies and interventions to improve coverage: a systematic review

BackgroundThe Cervical Cancer Elimination Initiative by the World Health Organization (WHO) has set a target of 90% human papillomavirus (HPV) vaccination coverage among girls by age 15 by 2030 to dramatically reduce deaths from cervical and other HPV-related cancers. However, progress has been slow, with only 27% global coverage in 2023. Migrants are considered an under-immunised group globally for many vaccine-preventable diseases, with data showing that they may experience a high burden of HPV infection and widespread HPV under-immunisation. Better understanding of the factors influencing the ability of these communities to get vaccinated for HPV is important. We aimed to systematically synthesise evidence on drivers of HPV vaccination uptake in migrants, and explored recommended approaches, strategies, and best practices to promote uptake in these communities. MethodsWe searched seven databases (e.g., Medline, Global Health) and websites (WHO, IOM, Google Scholar) for literature on drivers of HPV vaccination uptake among migrants globally, published between January 2006 and December 2024 in any language. Data on influencing factors for HPV vaccination uptake in migrants were extracted for an integrated approach to synthesising findings, and recommended strategies to improve it were compiled. We conducted a hybrid thematic analysis using the WHO BeSD model and assessed risk of bias with Joanna Briggs Institute checklists. PROSPERO protocol: CRD42023401694. FindingsWe identified 1,806 database records and 1,756 records from websites, ultimately including 117 studies with 5,638,836 participants across 16 countries and one territory (including 933,187 first- and second-generation migrants, mostly defined as foreign-born in high-income countries). Factors negatively influencing vaccine uptake included concerns about vaccine safety, cultural beliefs, uncertainty about HPV vaccines/infection, low knowledge of HPV/HPV vaccine, gender/sex, inter-generational and family dynamics, exposure to negative information, and lack of recommendations from healthcare providers. Practical barriers included limited information on services, language issues combined with a lack of skilled interpreters, logistical challenges, and the high cost of the vaccine. Enablers mainly included positive perceptions and trust in the vaccine and healthcare providers, realistic expectations from parents regarding the sexual activity of adolescents, a sense of responsibility, as well as recommendations from healthcare providers and support from social networks. Other positive predictors of vaccine uptake included being female, and having a history of vaccine-preventable diseases or abnormal Pap test results. Findings highlighted that free-of-charge and school-based schemes were effective in increasing uptake, while mandatory or optional schemes were less popular. Key recommended approaches included culturally sensitive messaging and tailored communication for different target groups (e.g., parents/caregivers, adolescents), with an emphasis on strength framing. Deploying trusted mediators (e.g., peer school health promoters, religious champions, community health workers) and implementing practical solutions to address missed opportunities (e.g., bundling HPV vaccination with other services) and for mobile migrants (e.g., eHealth) were also emphasised. Additionally, strong provider recommendations and reducing access barriers through measures including walk-in, mobile, and outreach services were recommended, alongside addressing broader cross-cutting issues, such as strengthening vaccine monitoring systems. InterpretationThis review showed that migrants worldwide face complex individual, family/social, and provider/system-level barriers to HPV vaccination, resulting in missed opportunities for protection. In many low- and middle-income countries (LMICs), the vaccine is either unavailable or has to be paid for. Achieving global commitments for universal and equitable immunisation across the life-course, making progress toward cervical cancer elimination, requires addressing these barriers through multi-pronged strategies. This includes combining effective health communication to build trust and address negative perceptions, along with efforts to eliminate physical barriers to vaccine access. Given the lack of data from LMICs, future research must urgently explore specific drivers of HPV vaccination among migrants in these regions where they are more concentrated and access to the HPV vaccine is limited, as well as develop solutions to system-level problems. Collaborative efforts with migrant communities are essential to co-develop effective, tailored delivery models that meet their unique needs. FundingThis research was funded by the NIHR (NIHR300072), the Academy of Medical Sciences (SBF005\1111), and the Medical Research Council (MRC/N013638/1).