A high incidence of bovine tuberculosis is a major impediment to the agricultural economies of many developing countries, including Latin America. This disease, which persists at lower incidences in Europe, can infect man and is a serious threat especially where AIDS is prevalent. Current methods to eradicate bovine tuberculosis use skin tests with crude antigens which lack specificity and cannot differentiate non-symptomatic cases from those with severe diseases (which spread infection). The present project will identify new antigens for use in better tests with defined applications as required in regions of different disease incidence. The tests will be optimised for field situations in Latin America (high incidence)and Europe (low incidence). Ultimately, antigens which are recognised by cattle with different levels of disease will be identified for use in efficient disease control programmes.