Study confirms the clinical impact of a BTV-3 outbreak on the UK sheep population

A recent study conducted by The Pirbright Institute has revealed the potential impact of the bluetongue virus serotype 3 (BTV-3) outbreak on the UK sheep population. The study was conducted after the detection of BTV-3 in cattle and sheep in the South of England in November 2023, marking the first UK BTV incursion in over 15 years. The virus, transmitted by Culicoides biting midges, has since spread across the East of England. Although it does not pose a threat to human health or the food chain, it can have a significant economic impact on rural communities. The research shows that the BTV-3 strain caused mild to moderate clinical disease in common UK sheep breeds and that infectious BTV-3 could be isolated in sheep blood up to 28 days after infection, suggesting that animals infected with this strain may be infectious to midges for a longer period than other European BTV strains. The authors of the study, published in Veterinary Record, emphasize the need for continued vigilance and reporting of clinical suspicions of bluetongue disease to control the spread of the virus.