Brucellosis is a contagious bacterial disease of livestock and a major zoonosis – it remains endemic in many parts of the world, posing a threat to food safety, causing economic losses and trade impacts. It primarily affects livestock, especially cattle, sheep and goats, and is caused by bacteria of the genus Brucella. Humans are most commonly infected through direct contact with infected animals or by consuming unpasteurized milk and dairy products. In animals, the disease is mainly associated with reproductive problems such as abortions, infertility and reduced milk production, and often requires laboratory testing for confirmation.

Beyond its direct health impacts, brucellosis is a major development challenge. In humans, it is a chronic and debilitating illness that can lead to long-term disability if not properly treated. In livestock, it causes significant production losses and trade restrictions, disproportionately affecting rural communities and pastoralists whose livelihoods and nutrition depend on livestock.

Because most human infections originate from animals, controlling the disease in livestock is the most effective way to reduce risks to people and improve food safety. Successful control requires sustained commitment and coordinated action across sectors, including strong surveillance and laboratory capacity, vaccination where appropriate, animal movement control, and a multisectoral One Health approach involving animal, human and environmental health authorities.

FAO's role

FAO supports countries in preventing, controlling and progressively eliminating brucellosis through a multisectoral One Health approach that integrates animal, human and environmental health. This work focuses on helping countries assess their epidemiological situation, strengthen surveillance and diagnostic capacities, and implement risk-based control strategies adapted to national contexts.

Through technical cooperation, FAO assists governments in strengthening veterinary services, surveillance systems and laboratory capacity, as well as workforce skills for disease detection and response. Support includes programme design, planning of targeted interventions, and monitoring and data management to ensure control strategies reflect local livestock systems and socio-economic conditions.

FAO also promotes coordination between animal and public health sectors and collaboration with international partners. By supporting capacity development, technical guidance and sustained programme implementation, FAO contributes to long-term brucellosis control that protects livelihoods, improves food safety and reduces zoonotic risk.

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