Worst Bluetongue Virus Outbreak Hits British Farms Amid Rising Temperatures

British farmers face the worst bluetongue season on record, with total cases already surpassing the past three years combined. The viral disease affects sheep and cattle, causing fevers, ulcers, a swollen head, lameness, and a tongue that can turn blue and stick out of the mouth, sometimes leading to death.

Spread and Cases

The virus originated in Africa and is spread by biting midges. It has moved into Europe over the last twenty years. The current strain, serotype 3 or BTV-3, was first found in England in 2023. Defra has recorded 2,201 cases in the current season running from 1 July 2026 to 30 June 2027, with 1,103 cases logged in September alone. A case is counted as a premises where at least one animal has the virus, meaning more animals are likely affected. The disease has now reached Scotland for the first time, spreading as far north as Aberdeenshire.

Impact and Challenges

Experts link the northern spread to hotter temperatures driven by the climate crisis, which helps the virus grow inside midges. National Farmers' Union vice-president Robyn Munt stated that farmers must keep constant watch for symptoms. She noted that getting vaccines has been very difficult because it is a demand-led process, adding extra stress and labor costs after a drought year.

Context

Warmer global temperatures allow insect-borne diseases that usually survive only in warmer regions to spread into new areas. While bluetongue does not harm humans or food safety, similar climate shifts have also led to invasive mosquitoes being found in London, highlighting broader health and agricultural challenges ahead.