A prioritised research agenda to inform the introduction and use of Lassa fever vaccines in West Africa

Building the evidence base for future Lassa fever vaccine decisions

Lassa fever is a viral haemorrhagic disease endemic in West Africa, and several vaccine candidates are currently in development. To help ensure that future vaccine decisions are timely, evidence-informed, and aligned with country needs, we convened a Policy Research Working Group to identify the most important research priorities for Lassa fever vaccines.

Using the Child Health and Nutrition Research Initiative methodology, the group carried out a two-phase prioritisation process. A rapid review of the literature and expert interviews first identified key evidence gaps, which were refined into 29 research questions across four thematic areas. These questions were then scored by 235 experts against five criteria.

The process identified 13 priority research questions, with strong agreement among experts. The highest-priority areas included defining vaccination target groups, assessing vaccine efficacy in special populations, evaluating the economic impact of vaccination, and understanding vaccine acceptance.

This stakeholder-driven research agenda highlights the critical evidence needed to guide vaccination policy, national decision-making, and implementation planning for future Lassa fever vaccines. Aligning research with policy needs early can help accelerate vaccine introduction and support equitable access in endemic regions.