RESUMEN
A benefit-cost analysis of vaccination for foot-and-mouth disease (FMD) was conducted in an area of South Sudan, which due to chronic conflict, had been subject to large-scale humanitarian assistance for many years. The study used participatory epidemiology (PE) methods to estimate the prevalence and mortality of acute and chronic FMD in different age groups of cattle, and the reduction in milk off-take in cows affected by FMD. The benefit-cost of FMD vaccination was 11.5. Losses due to the chronic form of FMD accounted for 28.2% of total FMD losses, indicating that future benefit-cost analyses for FMD control in pastoral and agropastoral areas of Africa need to consider losses caused by chronic disease. Participatory epidemiological methods were also used to assess the importance of milk in the diet of Nuer agropastoralists, and seasonal variations in diet in relation to cattle movements and FMD outbreaks. Marked seasonal variation in diet included a 'hunger gap' period during which households were highly dependent on milk as their main source of food. Outbreaks of FMD occurred immediately before this period of milk dependency, with chronic losses extending through this period and affecting human food security. The paper discusses the need and feasibility of mass vaccination and strategic vaccination for FMD in South Sudan. The paper also discusses the value of combining conventional benefit-cost analysis with livelihoods analysis to inform disease control efforts and funding commitments in humanitarian contexts.