Lumpy skin disease: Cirad mobilised as a national reference laboratory and disease expert

Lumpy skin disease (LSD) was detected for the first time in mainland France on 29 June 2025, on a cattle farm in Savoie. CIRAD acted immediately, deploying all necessary resources as the national reference laboratory (LNR) to conduct emergency diagnostics. It was able to identify over 51 outbreaks between 27 June 2025 and 30 July 2025, the first cases to affect mainland France.

Emergency diagnostics and training for departmental analysis laboratories

At that time, the LNR was the only laboratory with the diagnostic capacities for LSD, a disease that had never previously been detected in France. To enable rapid local diagnostics to be conducted in the areas affected, the LNR deployed LSD diagnostic capacities to the departmental analysis laboratories (LDAs) concerned, coordinated by the MAASA and the Directorate General for Food (DGAL). At the same time, the LNR offered technical assistance and expertise to the LDAs throughout the process. To date, five departmental analysis laboratories (Ain, Pyrénées-Orientales, Haute-Garonne, Pyrénées-Atlantiques, Savoie) have been granted temporary approval by the DGAL, following the recommendation of the LNR, and currently conduct LSD diagnostics throughout France.

Expertise and consultations on disease management

On 15 December 2025, the MAASA set up a scientific consultation committee in the Occitanie region to assess proposals from professional agricultural representatives in the region regarding possible changes to the sanitary protocol implemented to control the disease. On 22 December 2025, the committee concluded that, based on the current scientific knowledge and the sanitary situation, the protocol in place in France since the emergence of LSD could not be altered. The committee also recommended an additional in-depth risk analysis to inform public decisions on “the feasibility of targeted culling in areas where immunity has developed”.

The MAASA then entrusted CIRAD with the task of coordinating a team of scientific and technical experts to produce this risk analysis.

This process is led and facilitated by Philippe Caufour, a national and international virologist specialising in LSD and head of the LNR for ruminant poxviruses, together with an epidemiologist at CIRAD.

The group is made up of 20 experts, including:

• field experts representing farmers and veterinarians (GDS, Société Nationale des Groupements Techniques Vétérinaires) ;
• experts in risk management for diagnostics, control, and regulatory matters (DGAL, Ruminant Poxviruses LNR, CIRAD) ;
• national and international scientific experts (Spain, Italy, Balkan countries, EU and non-EU) (ENVT, INRAE, ANSES, CIRAD, international consultants, University of Barcelona, University of Liège).

The expert group will specifically examine the risk of viral dissemination and the potential failure to manage the sanitary situation in such a context.

To achieve this outcome, expected by the end of June, the working group will concentrate on:

• summarising and analysing the existing scientific knowledge on LSD (virus, epidemiology, experience in France, management of outbreaks outside France, including in the Balkans, diagnostic and vaccination tools currently available, existing transmission models, etc.) ;
• conducting a qualitative risk analysis to compare different scenarios in terms of effectiveness, feasibility, cost and acceptability ;
• drawing up recommendations to support the conclusions of the risk analysis.

Scientific research is ongoing, with a focus on the vaccine

CIRAD’s research on LSD, conducted over many years, focuses primarily on developing tools to control the disease. Efforts to create new vaccines have been underway for the past 10 years, with the goal of bringing to market safer vaccines with DIVA properties (“Differentiating Infected from Vaccinated Animals”) and lower residual virulence.

The vaccines currently used against LSD are live attenuated vaccines, including the one used in France to control the disease. Although they are effective in reducing morbidity and viral transmission, they retain residual pathogenicity that can cause visible post-vaccination reactions (skin nodules, fever, reduced milk production). In some epidemiological contexts, these effects may complicate disease management, clinical monitoring and the acceptability of vaccination for farmers.

Current vaccine strains do not enable serological differentiation between vaccinated and infected animals, which limits the ability to monitor viral circulation accurately and may delay the lifting of trade restrictions.