Study confirms the clinical impact of a BTV-3 outbreak on the UK sheep population New research shows potentially serious consequences of bluetongue virus serotype 3, which has been detected in UK cattle and sheep and in Northern Europe18 December 2024 18 December 2024 3 minute read 3 minute read By: By: The Pirbright Institute EuropeA new study highlights the potentially serious consequences of bluetongue virus serotype 3 (BTV-3) on the UK sheep population. In November 2023, BTV-3 was detected in cattle and sheep in the South of England through routine surveillance, making it the first UK BTV incursion for over 15 years. Severe clinical disease was reported in Northern Europe, whilst no clinical disease was reported in the few initial UK BTV cases in 2023, raising questions over the potential impact of a BTV-3 outbreak on UK sheep flocks. The findings, published today in Veterinary Record, show the BTV-3 strain caused mild to moderate clinical disease in a common UK sheep breed. Clinical signs of disease varied in nature and severity between individuals and included fever, haemorrhagic diarrhoea, lameness and behavioural changes such as depression and isolation.