A sheep on a farm in South Norfolk has been confirmed as the UK’s first official case of bluetongue disease this summer.
The case at the farm near Haddiscoe was reported on Monday, August 26.
Earlier this year, farmers were urged to remain vigilant for BTV-3 — a new strain of the bluetongue virus — amid a “high probability” of infected midges blowing over from Europe. Animal and Plant Health Agency (APHA) assessments in May concluded that there was “a very high probability” that the virus could reappear during the summer.
Countries including the Netherlands, Luxembourg, Germany, France and Denmark have seen a sharp rise in livestock cases, officials said.
The Norfolk case is not the first time bluetongue has been detected in the UK. However, the virus’s impact on farming in the UK has been relatively small.
There have been 126 documented cases of the virus in England, according to official reports.
There is no vaccine for the BTV-3 strain but emergency vaccines have recently been approved in parts of Europe.
So what is bluetongue, what are its symptoms and how can you prevent it?
What is bluetongue?
Bluetongue is caused by the bluetongue virus (BTV), which belongs to the genus Orbivirus within the family Reoviridae. The disease is transmitted by certain species of biting midges (Culicoides), which act as vectors for the virus.
Bluetongue primarily affects ruminants, animals with stomachs divided into four compartments and chew cud. The main species impacted by bluetongue disease include:
- Sheep: They are the most severely affected by the disease. Infected sheep can show significant symptoms including fever, swelling of the face, tongue, and lips, lameness, and sometimes even death. The severity of the disease in sheep can vary depending on the strain of the virus and the breed of the sheep.
- Cattle: While cattle can be infected with the bluetongue virus, they often exhibit milder symptoms or may be asymptomatic carriers. However, they can still play a role in the spread of the disease since infected cattle can harbor the virus and be a source of infection for midges, which can then transmit the virus to other animals.
- Goats: Like cattle, goats are generally less affected by bluetongue than sheep, but they can still be infected and contribute to the spread of the virus.
- Deer and wild ruminants: Wild ruminants including deer can also be affected by bluetongue. The disease can lead to significant morbidity and mortality in these populations, particularly in areas where the virus is newly introduced.
There were reportedly 800 outbreaks in Europe as of October 2023.
Can bluetongue spread to humans?
Humans are not susceptible to this virus. There is no risk of transmission from infected animals to people, either through direct contact, consumption of meat or milk, or through the bites of the midges that spread the virus among animals.
UK chief veterinary officer Christine Middlemiss said in 2023: “Bluetongue does not pose a threat to human health or food safety, but the disease can impact livestock farms, and cause productivity issues.”
How to prevent bluetongue
Farmers are urged to be vigilant, source their livestock responsibly, and practise good biosecurity to prevent the spread of bluetongue.
Previous outbreaks of bluetongue in the UK have resulted in swift action from local farmers and authorities.
The APHA implemented strict rules when bluetongue was detected and ensured that imported animals had compliant paperwork.
For instance, in November 2023 a cow was diagnosed with bluetongue and efforts were quickly introduced to limit the disease's spread.
The Government said the cow was culled to reduce the risk of onward disease transmission.
A 10-kilometre temporary control zone around the affected farm was also established.
Suspicion of bluetongue in animals in England must be reported to the Animal and Plant Health Agency on 03000 200 301.
