The UK is experiencing its worst bluetongue season on record, with cases in the first three months of the 2026-27 season exceeding the total from the previous three years combined.
Key facts
- •Defra has recorded 2,201 cases of bluetongue between 1 July 2026 and the end of September 2026.
- •The 2026-27 season has already recorded more cases in its first three months than the previous three seasons combined.
- •A 'case' is defined by Defra as a premises where at least one animal is infected, meaning the total number of affected animals is likely higher.
- •The virus has reached Scotland for the first time, with cases identified as far north as Aberdeenshire.
- •Experts have also observed mosquitoes capable of transmitting Zika and dengue viruses breeding in east London this summer.
British farmers are currently managing the most severe bluetongue outbreak on record, with the viral disease affecting sheep and cattle across the country. The current season, which began on 1 July 2026, has already surpassed the total case count of the previous three years. The virus, transmitted by biting midges, has spread as far north as Aberdeenshire, marking the first time the disease has reached Scotland.
By the numbers
Disease Impact and Transmission
Bluetongue is a viral disease that causes symptoms including fevers, ulcers, lameness, and swelling of the head. In severe cases, the disease can be fatal to livestock. While the virus does not pose a risk to humans or food safety, it creates significant labor and financial pressure for farm businesses, which must maintain constant vigilance to monitor for symptoms. The strain currently circulating in England is serotype 3 (BTV-3), which was first identified in the country in 2023. Experts link the spread of the virus to climate change, noting that warmer temperatures allow the midges that carry the virus to survive and develop in regions further north than previously possible.
Challenges for Farmers
Farmers are encouraged to vaccinate their livestock, but the National Farmers’ Union reports that securing vaccines has been difficult due to a demand-led supply process. This difficulty adds to the existing economic strain on farms, which have already faced increased costs due to climate-related droughts. Tom Cantillon of the Energy and Climate Intelligence Unit described the current outbreak as a sign of future trends. He warned that as winters become milder and summers hotter, the UK will likely see more frequent incursions of pests and pathogens that were previously unable to survive in the local climate.
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This article was independently rewritten by ManyPress editorial AI from reporting originally published by Guardian Science.
