An overview of the eradication of Brucella melitensis from KwaZulu-Natal

Abstract

Brucella melitensis is a Gram-negative bacterium whose primary hosts are goats and sheep. Like the other Brucella spp., with the exception of Brucella ovis, it is not particularly host specific as it is pathogenic for a variety of other mammal species including humans. In humans the disease caused by it is rated as one of the most important zoonoses. Three outbreaks have been recorded in goats and sheep in South Africa; the first outbreak occurred in sheep in 1965 in the Mpumalanga and Northern Provinces (then both part of the Transvaal Province), the second occurred in sheep in 1989 near Pretoria, Gauteng Province, and the third and current outbreak was diagnosed in a flock of goats in northern KwaZulu-Natal in September 1994. Following the initial diagnosis of B. melitensis in north-eastern KwaZulu-Natal, a serological survey was conducted in order to identify foci of infection in the goat and sheep populations. Six positive foci were identified. In March 1996 a test-and-slaughter eradication campaign was initiated in these areas. Initial test results revealed a prevalence of between 1.23% and 4.02%. All positive animals were identified and slaughtered. Eradication programmes were repeated between March 1996 and June 2000, in the populations at risk, and the disease prevalence was reduced in all the affected populations.