A systematic review of the determinants of vaccine hesitancy in the UK: Implications for future TB vaccine adoption

BACKGROUND: Tuberculosis (TB) is a deadly yet vaccine-preventable disease mostly affecting adolescents and adults. Novel TB vaccines are now emerging, particularly for these populations; however, vaccine hesitancy, characterised by delays, doubts or refusal to seek or accept vaccines, poses a challenge for sufficient adoption once these vaccines become available. Thus, this review systematically explored system- and individual-level determinants of vaccine hesitancy among adults in the UK, interpreting implications for the adoption of novel TB vaccines. METHODS: Five databases systematically searched for studies from 2020 - 2024 reporting qualitative outcomes on determinants of vaccine hesitancy among people living in the UK. Thematic analysis mapped extracted data onto a framework combining the Strategic Advisory Group of Experts (SAGE) model to explore system-level factors (e.g., vaccine-specific influences) and the Perceptions and Practicalities Approach (PaPA) to explore individual-level factors (e.g., perceptual influences) of vaccine hesitancy. The Mixed Methods Appraisal Tool was used to assess study quality. RESULTS: 29 qualitative and 21 mixed methods studies; 87.5% investigated hesitancy to COVID-19 vaccines. All SAGE themes were identified at the system level, most notably vaccine novelty, the media environment and health system experiences. At individual-level, all PaPA themes emerged, with vaccine-specific beliefs and knowledge most frequently identified. Overall, themes varied across the lifespan, with adolescents influenced mainly by media and social norms, and older adults by safety concerns and trust in health professionals. CONCLUSIONS: Vaccine hesitancy determinants interacted and were compounded in vulnerable subgroups, while post-pandemic disruptions to TB services may undermine adoption of novel TB vaccines. Addressing these challenges requires multi-level strategies centred on trusted, culturally sensitive communication. Delivery through routine, school and community-based programs aligns with evidence from high-incidence settings and highlights the need for coordinated action by policymakers and healthcare providers.