Digital health technology used in emergency large-scale vaccination campaigns in low- and middle-income countries: a narrative review for improved pandemic preparedness.

INTRODUCTION: Large-scale vaccination campaigns can benefit from using digital health tools, particularly in low- and middle-income countries (LMICs). Selecting the best tool to fit into a pre-existing digital landscape can be challenging. AREAS COVERED: We conducted a narrative review in PubMed and the grey literature for data available within 5 years to provide an overview of digital health tools used in large-scale vaccination campaigns for outbreak response in LMICs. We discuss tools used along the typical steps of a vaccination process. Digital tool functionalities and technical specifications, open-source options, data privacy and security concerns, and lessons learned from the use of these tools are discussed. EXPERT OPINION: The landscape of digital health tools for large-scale vaccination processes in LMICs is growing. For efficient implementation, countries should prioritize the appropriate tool(s) depending on their needs and available resources, develop a robust framework around data privacy and security, and select sustainable features. Improving internet connectivity and digital literacy in LMICs will facilitate adoption. This review may aid LMICs still needing to prepare large-scale vaccination campaigns in the selection of supporting digital health tools. Further research on impact and cost-effectiveness is needed.