Important events that preceded the Southern Africa Newcastle Disease Control Project (SANDCP) project are considered. Severe Newcastle disease (ND) was first described in the accessible scientific literature in the late 1920s.The disease rapidly spread around the world. Milder unremarked forms of the disease may have been present before this, with possible earlier severe episodes in Asia and Africa escaping historical notice. The developing commercial poultry industry at that time was obliged to cometo terms with this devastating disease. Flocks of village chickens had no protection from it. Early studies on the causative virus depended on transmission to chickens. In the 1930s, it was shown that the virus could be cultivated in embryonated eggs and that the virus could be easily quantitated by measuring its haemagglutinin. A simple haemagglutination inhibition test detected and titrated anti-viral antibody. These tests are still basic to studies on ND virus. Vaccines for use in commercial flockswere produced by the standard contemporary approaches for the control of serious veterinary diseases. Crude inactivated vaccines were produced first, then virulent virus was applied together with antiserum. A later refinement was the use of viable attenuated vaccines. These have served the commercial industry well but they have found little use in village chickens. There has been no tradition of vaccination in village flocks. The commercial vaccines have been too expensive and insufficiently robust forrural flocks. Unusual, avirulent strains of ND virus have been recognised in Australia since 1966. The first isolate, strain V4, was later developed as a commercial vaccine. When the Australian Centre for International Agricultural Research (ACIAR) was founded, an initial project (in 1984) was to develop a ND vaccine suitable for use in village chickens. The first trials, conducted jointly by the University of Queensland and the Universiti Pertanian Malaysia, used variants of strain V4, artificially selected for enhanced heat resistance. Following successful laboratory and field trials, ACIAR supported a regional approach, with confirmatory studies in Indonesia, Philippines, Thailand and Sri Lanka. In the initial trials, V4 vaccine was presented to chickens on food. This was a concession to the lack of physical control over the chickens at the time. Eye-drop vaccination has proved more effective and is now advocated where husbandry conditions are favourable. When V4 became a commercial vaccine, a newvaccine strain was required for village use, to avoid legal complications. ACIAR sponsored the development at the University of Queensland of a new vaccine master seed. The result was strain 1-2, another Australian avirulent virus that had properties, including heat resistance, similar to V4. The master seed, controlled by ACIAR and held at the University of Queensland, is available without cost to developing countries. Tests with the heat-resistant vaccines V4 and 1-2 have been undertaken in many countries in Asia and Africa. Some of the countries have adopted one or other of these vaccines and produced them on a large scale. Vietnam is a particular example where local initiative has seen full exploitation of the vaccine. Agencies other than ACIAR have become involved in the projects, supporting vaccine activities in country or training projects at home or in Australia. These agencies include the Food and Agriculture Organization of the United Nations, the United Nations High Commission for Refugees,the World Bank, the International Atomic Energy Agency and the Australian Agency for International Development. Many non-government organisations have been supportive.Vaccine production and testing was only the foundation for the successful projects. Sustainable vaccination campaigns have required in-country vaccine production, and this depended on appropriate training at international workshops or at the University of Queensland. Also essential t
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