Battle Bluetongue – information for vets

A: Defra’s Secretary of State has permitted the use of three unauthorised bluetongue serotype 3 (BTV-3) vaccines within the UK, subject to licence (16 September 2024).

A: The BTV-3 vaccines claim to reduce viraemia rather than prevent it. This means they may not prevent animals from being infected or infectious, but (depending on the vaccine) their claims include reduction or prevention of clinical signs and/or mortality.

A: The decision to vaccinate is a matter for farmers to discuss with their vet. It is impossible to predict the impact BTV-3 will have in 2025, but vaccination is of benefit in the case of significant disease and should be considered as an appropriate insurance to protect animals and businesses.

Our focus is to ensure that farmers and their private vets are fully informed of the current situation.

Vaccination will be less effective once disease is significant.

A: For serotypes where vaccines are available (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.

Vets can apply to the Veterinary Medicines Directorate (VMD) for a Special Import Certificate, which will allow livestock keepers to import safe and effective bluetongue vaccines directly from the EU.

A: All movement controls and trade restrictions still apply to vaccinated animals. This is subject to change; for the current status, please see: Bluetongue movement licences and designated slaughterhouses

(gov.uk/guidance/bluetongue-movement-licencesand-designated-slaughterhouses)

The BTV-3 vaccine cannot be used in Scotland and Wales at this time, but BTV-3-vaccinated animals from England (from the BTV-3-free area) are permitted to move into Scotland and Wales, as any other animal can.

A: Farmers should consider vaccinating animals if:

• There is a high density of ruminant farms in the area, particularly if any of these had confirmed cases of BTV-3 in 2024
• The farm is situated in a high-risk area (south/east England)
• They plan to buy in animals or to transport animals back home from distant sales or shows
• The weather conditions have been unseasonably warm
• They keep cattle, sheep and/or other ruminants or camelids Prioritise the following livestock:
• High-value breeding stock, rare breeds and pedigrees
• Animals not pregnant or in mid pregnancy
• Breeding males – particularly if they only have a few and expect them to serve lots of females

A: Like any sheep or cattle vaccine, there will be maternal transfer of immunity in the colostrum to lambs and calves, and this will protect newborns.

This immunity will wane over the first few months of life, and lambs and calves will require their own vaccination to be protected in the longer term.

The timing of this vaccination is important, as the maternal antibodies will inhibit the vaccine – the manufacturers’ recommendation for most vaccines (including BTV vaccines) is to wait 1–3 months before vaccinating lambs and calves.

A: If you have vaccinated your livestock, you will still need to test if you suspect BTV as the vaccine does not prevent infection.

A No the BTV-3 vaccines are only licensed against the bluetongue virus serotype 3.

While BTV-12 is currently lower priority, we are not aware of any plans to develop and licence a vaccine for serotype 12, however the situation for BTV-12 will continue to be monitored.