This study shows the absence of the world's most common bacterial zoonoses caused by Brucella abortus and Brucella melitensis in cattle, goats and dogs in an agro-pastoral community in South Africa, where heifer vaccination against brucellosis with the live Strain 19 vaccine is compulsory. The study site is bordering wildlife reserves with multiple wildlife species infected with brucellosis. The results showed a low seroprevalence (1.4%) in cattle. Seroprevalence in cattle decreased with age after 4 years in females, males were less positive than females and a tissue culture from a brucellin skin test-positive male was negative. The results indicate that Brucella seropositivity in cattle is due to S19 vaccination and not natural infections. This conclusion is reinforced by the absence of Brucella seropositivity in goats (1/593 positive result) and dogs (0/315), which can be seen as potential spillover hosts. Therefore, the close proximity of brucellosis-infected wildlife is not a threat to domestic animals in this controlled setting with vaccination, fencing and movement control.
- S19 vaccine
- South Africa
- Transfrontier Conservation Area