Culling protocol proposed for brucellosis outbreaks

The National Agency for Food, Environmental and Occupational Health Safety (Anses) has proposed a partial culling protocol for isolated brucellosis outbreaks in response to a request from the General Directorate of Food (DGAL) on September 3, 2024. This method involves strict sanitary measures that could last several months or even more than a year, and it awaits approval from French and European authorities.

Protocol targets specific outbreak scenarios

The proposed protocol is designed for specific cases involving isolated outbreaks, requiring strong cooperation from the farmer, a limited number of infected animals, and support from local actors such as veterinarians, the departmental directorate for population protection (DDPP), and health defense groups (GDS). It involves culling infected animals, followed by a rigorous cleaning and disinfection process, during which no new animals can be introduced or removed from the herd.

Strict limits on infection levels

Experts recommend a maximum infection threshold of 15%, with no more than 15 animals identified as infected or suspected of being infected. This limit must not be exceeded throughout the entire duration of the protocol. Farmers must request the protocol due to its specific requirements and operational constraints, and they must have a separate birthing area to prevent contamination and extra forage supplies until the farm is reclassified.

Health and safety precautions required

Brucellosis can be transmitted to humans, so all individuals working with animals must be informed of the risk and wear appropriate protective equipment. The approval of this method depends on its acceptance by French and European authorities, which will consider the proposed approach before implementing it.

France's brucellosis history

France was officially declared free of bovine brucellosis in 2005, in line with European regulations, with no outbreaks recorded between 2003 and 2011. However, two outbreaks were confirmed in 2012, prompting increased vigilance. In 2021, a brucellosis outbreak was identified on a dairy farm in Haute-Savoie, highlighting the need for continued monitoring and control measures.

Challenges in eradicating brucellosis

The bacteria responsible for brucellosis in cattle are primarily Brucella abortus, while Brucella melitensis affects sheep and goats. According to Florence Etoré, head of the unit for Risk Assessment related to Animal Welfare, Health, Animal Food, and Vectors, "The elimination of these bacteria is very complicated. They are persistent in the environment, and their detection in animals is difficult. Clinical signs are only visible during pregnancy and calving."