Although brucellosis has been, or is close to being, eradicated from a number of developed countries, it continues to be a major public and animal health problem in many regions of the world, particularly where livestock are a major source of food and income. There are many reasons why brucellosis remains endemic. These include expansion of livestock herds and flocks, with associated uncontrolled movements; lack of veterinary support services and vaccines; and husbandry practices favouring the spread of infection. Human cases continue to occur following international travel, traditional use of raw milk products and following close contact with infected animals.
The approach to control, prevention, or eradication of brucellosis in a country or region will depend on many factors, such as the level of infection in the herds or flocks, type of husbandry, economic resources, public health impacts, and potential international trade implications. Decision-making by those charged with policy making is likely to be intuitive unless accurate and current epidemiological information is available. The purpose of these general guidelines on surveillance in both human and animal populations is to provide a set of principles and techniques that can be used to develop and monitor new or existing brucellosis control programmes. The guidelines can also help in assessing the effectiveness of regulatory and advisory measures designed to safeguard public health.
In using these guidelines to develop new or to review existing surveillance systems, it is unlikely that adoption of all recommendations is possible, or even necessary. Rather, specific recommendations should be adapted to fit local or regional resources, needs, knowledge and practices, at least initially. As progress is made, changes can be incorporated to ensure that success is finally achieved. If progress is not made, then note should be taken of key epidemiological indicators, and corrections made on the basis of this information rather than for intuitive or political reasons.
