Bluetongue Virus

BTV is a notifiable disease which has the potential for rapid spread via biting midges to other ruminating animals with significant production losses in livestock. Suspicion of BTV in animals in England must be reported to the Animal and Plant Health Agency on 03000 200 301. In Wales, contact 0300 303 8268. In Scotland, contact your local Field Services Office. Failure to do so is an offence.

BTV is mainly spread by adult-infected midges (various Culicoides species) biting (vector) an animal susceptible to the disease. This is classed as ‘vector-borne’ transmission.

Infected midges can spread locally and more widely in certain temperatures and wind conditions.

The second but less common way the disease is spread is through movement of infected animals. That is why movement of animals from BTV areas is controlled.

The time of year, i.e. whether during the active vector season (normally March-September), and meteorological conditions, i.e. temperature and wind direction, and the proximity and density of neighbouring farms are significant factors in the potential incursion and spread of this disease. It is however possible to move infected animals at any time of year.

Control of midges is difficult and although there are things that can be done to reduce their spread, it is unlikely that the risk of them can be removed on any individual farm. Reducing the risk is therefore the aim.

The main preventative measure is movement controls and restrictions for susceptible livestock species in relevant areas to reduce the opportunity for vector transmission between holdings. Midges often accompany the animals as they move e.g. in livestock trailers, therefore moving animals increases the risk of midge spread too.

Synthetic pyrethroid (e.g. deltamethrin)-based pour-on insecticidal products are approved in the UK for use on cattle and sheep against some biting flies and lice. In laboratory conditions, deltamethrin is a highly effective toxin for Culicoides (midges). However, their efficacy has not been shown outside of the laboratory, and they have not been proven to have a direct impact on BTV transmission.

Deltamethrin-based products can be used at maximum levels recommended by the manufacturer and may at least reduce the biting pressure on an animal, although this effect will be temporary. The same active ingredient would be appropriate for spraying of housing/trailers for animal movement.

Please follow product label recommendations and adhere to responsible use guidelines when using insecticides to ensure no environmental adverse affects to non-target organisms.  

Midges breed in damp soils with high organic content, such as muckheaps. So, keeping these distant from susceptible livestock and livestock-housing may reduce biting frequency and therefore BTV transmission.

Unless specifically directed to by an inspector, or instructed to by the conditions of an official notice, declaration or licence, you are not required to house ruminant animals at your premises. However, you may wish to consult your veterinary surgeon for advice on any protective steps you might take.

Details can be found here – Bluetongue: GB disease control strategy – GOV.UK (www.gov.uk)

The number for the Bluetongue hotline is 024 7771 0386. NFU members can also access the CallFirst hotline: 0370 845 8458

There are several serotypes of BTV but vaccines are only available for certain serotypes. Unfortunately, there are no authorised vaccines for BTV3 in the UK or EU. Vaccination against BTV3 is therefore not possible.

Vaccines do not offer cross-protection, i.e., vaccinating your animals against BTV8 will not protect them from infection with BTV3.

Unfortunately, there are no authorised vaccines for BTV3. Vaccination against BTV3 is therefore not possible.

The decision to vaccinate against other strains of BTV is a matter for farmers based on the possible impacts for their businesses. In the current situation we do not believe there is a case for mandatory vaccination, nor for the Government to provide or fund vaccination. Our focus is to ensure that farmers and their private vets are fully informed of the current situation.

For serotypes where vaccination is possible (such as BTV 1, 2, 4 and 8), vaccination is the best way to protect livestock. Livestock keepers should discuss with their vet whether vaccination is an option which will benefit their business. Veterinary surgeons can apply to the Veterinary Medicines Directorate for a Special Import Certificate, which will allow keepers to import safe and effective bluetongue vaccine directly from the EU to vaccinate their stock. 

Because BTV is transmitted by midges carrying the virus, and not from one animal to another, vaccination will not necessarily prevent all future potential disease spread but would enable farmers to protect their own herds.   

Unfortunately, there are no authorised vaccines for BTV3 in the UK or EU. Vaccination against BTV 3 is therefore not possible.

• Following confirmation of BTV in a non-imported animal in England, the UK may no longer be considered as a BTV-free country.
• Trade with trading partners, including trade to the EU, may be subject to additional control measures imposed by the importing authority.
• Some countries may restrict UK exports of susceptible animals or their products as a result, although it is expected that exports of many commodities will be able to continue. In some cases, there may be a requirement for additional checks, testing or treatments.
• The latest information on availability of individual export Health Certificates can be found via Get an export health certificate – GOV.UK (www.gov.uk)

To protect the biosecurity status of Northern Ireland movement of susceptible livestock from GB will now be stopped as epidemiological investigations continue. Movement of germplasm will be subject to appropriate restriction.

Action is being taken to ensure the risk of spread of the disease is reduced – the infected cow has been humanely culled to reduce the risk of onward disease transmission and livestock movements from the affected premises are restricted.

We have also put in place a 10km temporary control zone around the affected farm which will restrict movements of susceptible animals except under license in that wider area, while we undertake additional surveillance to assure ourselves this is an isolated case. The fact that this single case was picked up shows our surveillance programme is working.

We have robust rules and procedures in place to protect our borders from disease and animals or their germinal products can only be imported if they meet these. It is essential that keepers source responsibly.

Over and above this, we carry out compulsory post-import testing of susceptible animals from areas around and known to have BTV infected regions.

The main direct economic impacts will vary depending on the strain of BTV and at this stage, with only one animal infected, we cannot make such assessments.  

Bluetongue can reduce milk yield, cause sickness, and reduce reproductive performance. The imposition of movement controls may require some farmers to change their usual routes to markets.  Farmers may incur costs from reduced market access, including export markets.

As a notifiable disease, the control of bluetongue is legislated for. The control strategy includes good biosecurity and animal care, responsible sourcing of animals, monitoring of the disease situation in Europe and internationally, and having in place appropriate risk-based import conditions and testing.

Vigilance by animal keepers is key. Anyone keeping an animal must notify any suspicion of notifiable disease. This will be investigated by government veterinary inspectors.