Bluetongue Surge Sweeps Britain and Ireland as Warm Weather Amplifies Midge Activity; Vaccination Urged Ahead of Autumn Risk

Britain’s sheep sector is facing its sharpest bluetongue surge in years — with more than 590 cases reported in a single week — as warm, humid conditions fuel midge activity across England, Wales and Ireland, prompting urgent calls for vaccination as the disease spreads beyond sheep into cattle and camelids on both sides of the Irish Sea.

Britain’s bluetongue situation has deteriorated rapidly, with the National Sheep Association reporting more than 590 confirmed cases in a single week. Defra says 12 cases of bluetongue serotype 3 have been confirmed in England since 1 July, with the 2026/27 season opening when a ewe in Staffordshire tested positive on 10 July. Cases are concentrated in south-west England and Wales — particularly Devon, Somerset and Cornwall — with affected animals including sheep, cattle and at least one llama.

The disease, spread by biting Culicoides midges, causes fever, swelling and prolonged recovery, and is flourishing in conditions that favour insect activity. The National Farmers’ Union says producers are moving vulnerable stock away from wet, sheltered land and housing animals at dawn and dusk when midge numbers peak, though reporting systems are struggling to keep pace with case volumes.

In Ireland, the picture is equally concerning. The first BTV-3 case was confirmed in a County Wexford suckler herd in January 2026 following slaughter surveillance, with historic infections subsequently identified across nine counties. Irish authorities believe infected midges blown across the Irish Sea in late autumn 2025 introduced the virus, and officials now warn temperatures have been high enough for overwintered midges to become infectious again ahead of autumn.

Irish Agriculture Minister Martin Heydon has authorised bluetongue vaccination in 2026 and incorporated it within Beef and Sheep Welfare Schemes. Both governments are urging farmers to discuss vaccination with their vets — with immunity requiring approximately 28 days to establish, the window for pre-autumn protection is narrowing.