Evaluating Management Strategies for the Lumpy Skin Disease Outbreak in France
Researchers used epidemiological modeling to analyze management strategies for the 2025 Lumpy Skin Disease outbreak in France. The study demonstrates why selective depopulation of herds is less effective than total herd culling in controlling the rapid spread of the virus among cattle.
Highlights
- •Lumpy Skin Disease caused major impacts on French cattle farms throughout 2025.
- •Authorities successfully managed the outbreak using emergency vaccinations and total herd culling.
- •Epidemiological models indicate that selective depopulation is unlikely to contain the virus effectively.
- •Future disease management will involve navigating a partially vaccinated bovine population.
Throughout 2025, the Lumpy Skin Disease (LSD), also known in French as dermatose nodulaire contagieuse (DNC), significantly impacted cattle farms across France. To manage this outbreak, authorities relied on emergency vaccination campaigns and the complete culling of affected herds. Researchers have recently utilized epidemiological modeling to determine if alternative management strategies, such as the selective culling of only diseased animals, could have effectively controlled the spread of this viral infection.
While Lumpy Skin Disease has been spreading in southern Europe, including recent detections in Sardinia, Italy, no new cases have been identified in France since January 2, 2026. This period of stability follows the intensive sanitation measures implemented during the previous year. The initial cases in France were detected in June 2025 in the Savoie department, subsequently spreading to the Auvergne-Rhône-Alpes region. By October 2025, the virus had moved into the Bourgogne-Franche-Comté and Occitanie areas, raising substantial concerns regarding a large-scale epidemic.
Epidemiological Insights on Disease Transmission
The virus causing Lumpy Skin Disease is primarily transmitted between cattle by the Stomoxys calcitrans, a biting fly found in high densities within stables. Because these flies are easily disturbed while feeding, they often move between multiple hosts, facilitating rapid viral transmission that is difficult to curb. While the government's strategy of total herd depopulation and emergency vaccination was successful, it drew heavy criticism from the agricultural sector. Critics frequently proposed "selective depopulation"—regular testing combined with the euthanasia of only infected individuals—as a preferred alternative.
To evaluate this proposal, researchers developed a mechanistic mathematical model to simulate viral transmission in a herd of 100 cattle. Their findings indicate that a single infected cow can transmit the virus to an average of 19 other animals through fly bites, establishing a high basic reproduction number. Simulations suggest that without intervention, there is a 91 percent probability that an entire herd of 100 cows would become infected within 51 days.
The models further analyzed the effectiveness of selective depopulation. Simulations involving testing the entire herd every two days showed that, despite such efforts, the herd would ultimately face complete infection. This outcome is attributed to the delay between the introduction of the virus and the detection of the first case, as well as the presence of asymptomatic animals that continue to contaminate the fly population. Consequently, the research underscores that there is no universal optimal strategy; management decisions must balance economic losses, animal welfare, and specific local environmental factors. Future research is now focused on how these dynamics change within a partially vaccinated cattle population.
