The use of vaccination in the control of bluetongue in southern Africa.

The eradication of bluetongue virus (BTV) from endemic regions of Africa is virtually impossible due to the role played by widely distributed Culicoides spp. midge vectors and the ubiquitous distribution of vertebrate reservoir species. In endemic areas, attempts can only be made to limit the occurrence of bluetongue (BT) disease and its economic impact through vaccination. Despite several potential problems (teratogenicity, risk of reassortment, and reversion to virulence of the attenuated viral strains), the current live-attenuated vaccine, produced by Onderstepoort Biological Products (OBP), South Africa, has been used for decades in enzootic regions, and has been shown to provide a safe and efficacious means to control the disease in regions of southern Africa, as well as other areas of the world.