In the heart of UK farming communities, the emergence of infectious diseases among livestock is a persistent concern.

Among these threats is bluetongue – a viral disease predominantly affecting sheep, cattle and goats – which has surfaced as a significant challenge. This viral disease has spread across parts of Europe and has recently been detected in the UK, raising concerns among our farmers and animal health experts.

In this article, Ester Benguerel, Food Safety and Animal Welfare Technical Lead at Eville & Jones, explains everything you need to know about the virus and what measures are being taken to safeguard the nation’s vital livestock.

Transmission and risks

Bluetongue is a viral disease of ruminants and is spread by the bite of midges. Historically, the UK’s relatively cool climate provided protection against these vectors establishing permanently. However, rising temperatures associated with climate change mean more areas of the UK now offer suitable habitat.

Once infected, the midges transmit the virus for life. Bluetongue outbreaks often peak in late spring and summer when the midge population is at its highest. The virus can overwinter in cattle then infect midges again in spring.

Signs and symptoms

Bluetongue can exhibit a range of clinical signs in affected ruminant animals, particularly cattle and sheep. The severity of these signs can vary depending on the strain of the virus, the host species, and the animal’s age and health status.

Common symptoms include fever, swelling of the face and tongue – which gives the disease its name – and excessive salivation. In severe cases, affected animals may experience lameness, difficulty breathing, and, tragically, internal bleeding leading to a high mortality rate.

It’s important to note that some infected animals may show only mild symptoms.

Post-mortem lesions

Upon postmortem examination, veterinarians often observe specific signs indicative of bluetongue. These may include haemorrhages in organs, particularly the heart, lungs, and digestive tract.

Swelling in the head and neck region, along with congestion in the mucous membranes, is also commonly noted. It’s also important to note that the severity and distribution of these lesions can vary depending on the strain of the bluetongue virus, the host species, and the stage of infection.

Looking ahead

While bluetongue remains an endemic disease threat across parts of Europe, the UK is navigating the challenges posed by the virus in 2023. A collective commitment to vigilance through surveillance and proactive measures becomes imperative.

Farmers, veterinarians, and governmental agencies must work hand-in-hand to protect the health and well-being of the nation’s sheep and cattle populations.

Recognizing the clinical signs during the animals’ lives and postmortem signs in deceased animals is central to mitigating the impact of bluetongue and ensuring the resilience of the UK’s vital livestock industry.

For more information on our Official Controls, go to our Services page, and to find out how you can join our growing team of veterinarians, visit our Join The Team page.

You can also get more information on how to spot and report bluetongue from the government’s official website here.