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Of the approximately 374 million cattle in Latin America and the Caribbean, 70% are held in areas where rates of Mycobacterium bovis infection in cattle are higher than 1%. The remaining 30% are in countries where infection affects less than 1% of cattle, including 62 million in countries where bovine tuberculosis infection is virtually nil. Measures for controlling bovine tuberculosis are partially or extensively applied in most of the countries in the Region. These measures are based on test and slaughter, notification, post-mortem inspection and surveillance in slaughterhouses. A coordinated production, standardization and quality control of purified protein derivatives is urgently required for use in control and eradication campaigns in order to assure reliability of reagents and comparability of data on tuberculin testing within the Region. On the basis of information from Argentina, M. bovis is estimated to cause 2% of all human cases of tuberculosis in the Region. Slaughterhouse and dairy farms workers are most-frequently infected, with infection occurring via the respiratory tract. Various in vitro assays for the diagnosis of bovine tuberculosis have been developed and/or assessed in the Region, and DNA fingerprinting has been applied for a comprehensive understanding of the epidemiology of bovine tuberculosis at the local and regional level.

Bovine tuberculosis is one of the most complex animal health problems that the farming industry in Great Britain faces today. In leading and facilitating the changes to policy required to reverse the long-term upward trend in the disease, Government is heavily reliant on evidence emerging from its wide-ranging bovine tuberculosis research programme. The paper outlines development of policy in Great Britain and its relationship to research findings.

The paper reviews the eradication of bovine tuberculosis from Australia with special reference to surveillance and managing the risk of animals exposed to tuberculosis infected animals during the latter stages of eradication. The successful eradication was based on a sound technical program with strong industry and government support. The model of joint industry and government funding and decision-making first used during the brucellosis and tuberculosis eradication campaign (BTEC) has been successfully incorporated within subsequent livestock disease control programs in Australia. An overview of the history of tuberculosis eradication in Australia provides a background to the surveillance approach. Australia was fortunate that there were no wildlife reservoir hosts. Feral animal reservoir hosts were removed during the eradication program. Surveillance to detect rare diseases is recognised to be statistically challenging with high resource requirements. Australian veterinary authorities have a high level of confidence that the combination of increasing sensitivity of abattoir surveillance systems by the submission of all granulomas detected at slaughter with increasing risk management of animals exposed to tuberculosis infected animals during the final stages of eradication provides a high level of assurance that Mycobacterium bovis has been eradicated.

Abattoir, or slaughter, surveillance has been an important component of bovine tuberculosis control and eradication programs in the U.S., and has adapted to changes in the livestock market from farm to table, and the threat of bovine tuberculosis from a wildlife reservoir. The purpose of this overview was to describe the current goals of U.S. bovine tuberculosis slaughter surveillance, describe the elements of slaughter surveillance in the U.S., describe enhancements to the slaughter surveillance system, and discuss future challenges for the U.S. bovine tuberculosis surveillance program. Government regulations and the scientific literature were examined to provide information for this paper. The control and eradication of bovine tuberculosis in livestock falls to the United States Department of Agriculture and two agencies within the Department: the Food Safety and Inspection Service (FSIS) and the Animal and Plant Health Inspection Service (APHIS). FSIS conducts routine slaughter surveillance for disease or conditions that render carcasses unsuitable for human consumption, while APHIS is involved in antemortem bovine tuberculosis testing, and necropsy and investigation of bovine tuberculosis cases identified through slaughter surveillance or antemortem testing. Results from the previous 5 years of surveillance are presented. Enhancements have been added to the current surveillance system to improve its performance. An incentive program has been used to increase the numbers of tissues submitted for laboratory examination, the state of Michigan is implementing electronic animal identification under a pilot program, and expansions to the current system are being developed to accommodate new livestock industries. The success of these programs and challenges for the future are discussed.

In the later stages of eradication of tuberculosis in cattle there is a need to take account of the fact that Mycobacterium bovis infection in cattle presents, not as cases of clinical disease but most commonly as apparently healthy animals showing an immunological response to tuberculin. This is an entirely different scenario to that seen when national eradication programmes were first devised, at a time when the protection of public health rather than animal health was the prime motivation. In countries with active programmes to eradicate bovine tuberculosis, it is critical for the programme's success that account is taken of this redefinition of tuberculosis, side by side with changes in modern animal production systems and their impact on the transmission of M. bovis. This paper highlights factors critical to the success of a national eradication programme, including a clear identification of the goals, of the policies that guide actions, and of the sequences of actions that are required within the programme to accomplish these goals. Experience has illustrated the adverse effects of compromise on outcome when the application of fundamental principles of disease control such as sound animal management, removal of known sources of infection, early diagnosis, quarantine, movement control and environmental hygiene are less than enthusiastically promoted and applied. The reality is that where these principles are applied in a sustained manner, the outcome is more likely to be successful. Therein lies the challenge for the risk manager.