Typhoid conjugate vaccine implementation in India: A review of supportive evidence.

BACKGROUND: Typhoid conjugate vaccines are available in the private market in India and are also recommended by the National Technical Advisory Group on Immunisation (NTAGI) for inclusion in India's Universal Immunisation Programme in 2022 to control and prevent typhoid fever. Our study aims to synthesise the supportive evidence for typhoid conjugate vaccine implementation in the routine immunisation programme of India. METHODS: We conducted a literature review to identify supportive evidence for typhoid conjugate vaccine implementation in India based on the key criteria of the World Health Organisation's Evidence-to-Recommendation framework for National Immunisation Technical Advisory Groups. RESULTS: We synthesised evidence on typhoid disease burden, benefits and harms of typhoid conjugate vaccine, cost-effectiveness analysis, and implementation feasibility. However, the in-country evidence on budget impact analysis, vaccine demand and supply forecast, equity analysis, target population values and preferences, immunisation service providers' acceptability, co-administration safety, and antimicrobial resistance tracking were limited. CONCLUSION: Based on the literature review, we identified evidence gaps. We recommend identifying research priorities for supporting typhoid conjugate vaccine implementation decision-making in India by combining evidence gaps with the perceived importance of the same evidence criteria and factors among immunisation stakeholders.