| Recovery from an attack of rinderpest has long been known to confer lifelong immunity to the disease. Early attempts to immunize cattle artificially were unpredictable and often disastrous. In the pre-Jennerian manner, used to protect humans against smallpox, cloth setons soaked in "matter" from a sick animal were inserted into the subject's skin. The discovery in Russia in the late nineteenth century of the protective powers of serum drawn from a recovered animal (Semmer, 1893) led shortly thereafter to the development in South Africa of the serum-virus simultaneous immunization method (Kolle and Turner, 1897). The method was in vogue for nearly 35 years. As the source of the virus for immunization was the blood of a reacting ox, the risk of inadvertently injecting other bovine pathogens was high. Edwards (1928) attempted to obviate the risk by passaging the virus serially in goats and, in me process, fortuitously developed an attenuated goat-adapted virus that could be injected alone into cattle without serum. This vaccine, together with the development of lyophilization (freeze-drying) techniques in the late 1930s, revolutionized the control of rinderpest. Mass national and continental campaigns followed. The global prevalence of rinderpest reached its lowest level in 1976, when its presence was reported from only three countries. There has since been a resurgence in Africa, India and the Near East. Vigorous application of multinational eradication campaigns has curbed the resurgence so successfully, however, that active disease is restricted to defined pockets in Africa and Asia. The incidence today is the lowest it has ever been.
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