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Participatory epidemiology (PE) was used on the Borana plateau of southern Ethiopia to understand pastoralist's perceptions of the clinical and epidemiological features of foot and mouth disease (FMD) in cattle. Matrix scoring showed good agreement between informant groups on the clinical signs of acute and chronic FMD, and findings were cross-checked by clinical examination of cattle and assessment of previous clinical FMD at herd level by detection of antibody to non structural proteins of FMD virus. The positive predictive value of pastoralist's diagnosis of FMD at herd level was 93.1%. The annual age-specific incidence and mortality of acute FMD in 50 herds was estimated using proportional piling. The estimated mean incidence of acute FMD varied from in 18.5% in cattle less than two years of age to 14.0% in cattle three to four years of age. The estimated mean mortality due to acute FMD varied from 2.8% in cattle less than two years of age to 0.3% in cattle three of age or older. Pearson correlation coefficients for acute FMD by age group were -0.12 (p>0.05) for incidence and -0.59 (p<0.001) for mortality. Estimates of the annual incidence of chronic FMD varied from 0.2% in cattle less than two years of age to 1.8% in cattle three to four years of age. The Pearson correlation coefficient for the incidence of chronic FMD by age group was 0.47 (p<0.001). Outbreaks of FMD peaked in Borana cattle during the two dry seasons and were attributed to increased cattle movement to dry season grazing areas. The mean seroprevalence of FMD was estimated at 21% (n=920) and 55.2% of herds (n=116) tested seropositive. Serotyping of 120 seropositive samples indicated serotypes O (99.2%), A (95.8%), SAT 2 (80%) and C (67.5%). The endemic nature of FMD in Borana pastoral herds is discussed in terms of the direct household-level impact of the disease, and the increasing export of cattle and chilled beef from Ethiopia.

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.

Because of severe resource and logistical constraints in large areas of Africa, disease surveillance systems need to maximize the use of information provided by livestock keepers and make correct interpretations of indigenous livestock knowledge. This paper describes the use of participatory epidemiology (PE) to compare the names, clinical signs and epidemiological features of cattle diseases as perceived by pastoralists and veterinarians. Using results from two previous studies with pastoralists in southern Sudan and Kenya, provisional translations of local disease names into modem veterinary terminology were used to develop a matrix scoring method for use with veterinarians. Matrix scoring data from pastoralists and veterinarians were then compared using simple visual comparison of summarized matrices, hierarchical cluster analysis and multidimensional scaling. The results showed good agreement between pastoralists' and veterinarians' disease names and diagnostic criteria. The matrix scoring method was easy to use and appropriate for use in under-resourced areas with minimal professional support or laboratory services. Matrix scoring could be used to assist livestock disease surveillance workers to design surveillance systems that make better use of pastoralist's indigenous knowledge and correctly interpret local disease names. The method should be combined with conventional veterinary investigation methods where feasible.