Brucellosis and bovine tuberculosis prevalence in livestock from pastoralist communities adjacent to Awash National Park, Ethiopia

This cross-sectional study investigated the prevalence of brucellosis and bovine tuberculosis (BTB) in local cattle and goat breeds of Oromo and Afar pastoralist communities living in two distinct parts around the Awash National Park. A questionnaire survey was carried out to assess information on husbandry, milk consumption habits, and on knowledge-attitude-practice regarding both diseases. Among a total of 771 animals from all sites tested by comparative intradermal tuberculin test (CIDT) none were BTB reactors with the <4mm cut-off. Using the <2mm cut-off, individual apparent prevalence was 0.9% (95%CI: 0.23-3.56%) in cattle and 0.7% (95%CI: 0.12-3.45%) in goats. Herd prevalence in Oromia and Afar sites was 0% and 66.7% respectively in goats and 16.7% and 50% in cattle. Among the 327 animals tested by enzyme linked immunoassay for brucellosis, 4.8% (95%CI: 1.2-17.1%) of cattle and 22.8% (95%CI: 5.98-29.5%) of goats were reactors. Highest individual prevalence of both diseases was found in Afar settlements with brucellosis being as high as 50%. Respondent ethnicity was the only risk factor for brucellosis positivity in goats in the univariable risk factor analysis. Knowledge about the diseases was poor. Raw goat milk was regularly consumed by women and children, putting them at risk for brucellosis. This study highlighted an increased prevalence gradient of BTB and brucellosis from West to East along the study sites with high brucellosis individual prevalence and abortion rates among Afar settlements in particular.