Determinants of COVID-19 and non-COVID-19 vaccine confidence in low- and middle-income countries: A systematic review of qualitative evidence and thematic synthesis

The COVID-19 pandemic has shown the immediate risk for global and public health posed by vaccination inequities worldwide. The regions most affected are low- and middle-income countries (LMICs). In addition to systemic challenges, vaccine hesitancy driven by low vaccine confidence has been identified as a threat to vaccine uptake. The aim of this systematic review of qualitative literature is to explore the determinants of COVID-19 and non-COVID-19 vaccine confidence in LMICs. A systematic review was conducted following the PRISMA and ENTREQ guidelines. The electronic databases Cinahl, Embase, Pubmed, Scopus and Web of Science were searched for qualitative studies focusing on the topic of interest in LMICs published between 2013 and 2023. The quality of the studies was assessed using the Joanna Briggs Institute's Checklist for Qualitative Research. A thematic synthesis was conducted. The study was registered on the Open Science Framework platform. 66 studies were included in the review. Three main determinants of vaccine confidence were identified: (1) General perceptions of the safety and efficacy of vaccines; (2) Information and experience; (3) Trust in healthcare providers, institutions, and systems. General perceptions of vaccine safety and efficacy were similar between COVID-19 and non-COVID-19 vaccines, and doubts regarding vaccine safety were neither new nor exclusive to the COVID-19 vaccine, indicating a persisting challenge. Furthermore, low vaccine confidence was partly determined by broader dynamics of mistrust towards Western countries and institutions, which was reflected for both vaccine groups. While conspiracy theories have been persisting determinants of low confidence, low COVID-19 vaccine confidence was partly determined by what was perceived as a lack of specific information. Persistent challenges to vaccine confidence were identified, rooted in colonial legacies and global health inequities, as well as limited intercultural approaches to building trust with regards to vaccines.