Livestock vaccination during humanitarian crises in Sub-Saharan Africa: a scoping review of evidence of impact.

BACKGROUND

In Sub-Saharan Africa (SSA), livestock are central to livelihoods and food security for hundreds of millions of people, yet are acutely vulnerable during humanitarian crises including drought, conflict, and disease outbreaks. Mass vaccination is routinely deployed as an emergency livestock intervention, but evidence of its actual impact on herd survival, livelihoods, and human nutrition remains scarce and methodologically weak.

METHODS

This scoping review synthesized available evidence on livestock vaccination during humanitarian crises in SSA, drawing on 57 sources identified through structured database searches supplemented by grey literature and expert workshop insights.

RESULTS

Of these, only 20 directly addressed vaccination in crisis or disaster-response contexts, nine reported direct measures of impact such as mortality reduction, herd recovery, or economic outcomes and eleven comprising of guidance documents or programme reports without outcome measurement. Most relied on coverage figures, programme reports, or operational guidance rather than rigorous outcome evaluation. Findings are labelled according to their context of origin: crisis setting (CS), non-crisis setting (NCS), or programme guidance (PG). Three studies from Kenya and Ethiopia reported reduced livestock mortality, while one study from South Sudan reported a positive benefit-cost ratio in a crisis context with vaccination associated with reduced livestock mortality and positive economic returns, particularly when implemented early and integrated with feed, water, and veterinary support. Key barriers to effectiveness included cold chain failures, delayed delivery, antigenic mismatch, weak coordination, and inequitable access, with women consistently less likely to benefit from vaccination programmes.

CONCLUSIONS

Based on this review, we recommend: (1) shifting evaluation frameworks from coverage outputs to measurable livestock and livelihood outcomes; (2) investing in preparedness and pre-crisis vaccination before animals are debilitated; (3) adopting thermostable vaccine formulations for remote and crisis settings; (4) systematically integrating gender equity into programme design and monitoring; and (5) prioritizing rigorous crisis-specific evaluation to strengthen the evidence base. Evaluation of crisis-response livestock vaccination remains methodologically weak and further rigorous evaluation is urgently needed.