Joint human and animal vaccination strategies to reach mobile pastoralists and their livestock in Africa: A scoping review.

Africa's pastoralist population exceeds 268 million and occupies over 40% of the continent's land. Mobile pastoralists connected to their livestock are underrepresented in data and face barriers to accessing fixed vaccination services. We aimed to identify and describe joint human-animal vaccination strategies to improve immunisation coverage among mobile pastoralists and their animals. We conducted a scoping review and followed Joanna Briggs Institute and PRISMA-ScR guidelines. We screened 2469 records from 12 databases. Five studies (2004-2016) from Chad, Nigeria, and Somalia met the inclusion criteria. Joint vaccination campaigns were implemented in three phases: planning, implementation, and post-vaccination. A participatory approach across both the planning and implementation phases was a key enabling factor and was operationalised through multiple mechanisms, including intersectoral collaboration, and community engagement. These joint vaccination campaigns improved vaccination coverage among children and women, and among livestock, compared to baseline, though animal outcomes were less emphasised. These strategies are promising as an equitable approach for mobile pastoralists. Future research should assess their cost-effectiveness and added benefits for animal health, which potentially lead to broader human health gains beyond vaccines.