Sheep farming

Bluetongue threat to the UK

There has been much information on bluetongue in the press of late discussing the risk of a disease incursion into the UK.

Bluetongue is a notifiable disease of ruminants caused by infection with the bluetongue virus (BTV). There are a number of different strains or serotypes but the one currently circulating in France and of concern to the UK is serotype 8 (BTV-8).

The main route of transmission of disease is via the Culicoides biting midge. Climate change and warmer winters has allowed wider distribution of these midges allowing bluetongue in recent years to extend into most of Europe and the UK.  Infection is transmitted when biting midges are most active, between May and October.

The effectiveness of disease control in France is important in terms of risk of a disease incursion into the UK. Movement restriction zones now cover most of France and vaccines are being used and targeted at animals in pedigree breeding programmes, animals destined for trade and those moving out of the restriction to the free zone.

Figure 1 - Map showing confirmed BTV-8 outbreaks and restriction zones in France as of 19th May 2016.

clincal signs of bluetongue in sheep

Figure 2 - Clinical signs in sheep (© Pirbright Institute)

Protection against bluetongue is through keeping susceptible animals away from the vector (the midge) and vaccination. Pour-on insecticides are helpful but do not achieve total freedom from the midge, and therefore vaccination is the only sure way to protect animals against infection. Vaccination played a key role in keeping the UK free from circulating disease in 2008-2009 following the prior outbreak. 

Since 2012 there have been no restrictions on use of bluetongue vaccines meaning farmers can choose to vaccinate at any time. Pre-emptive vaccination offers the most effective strategy for ensuring animals are protected prior to disease entry into the UK.

Vaccines against BTV-8 will be available in the UK from July; Zulvac® 8 Ovis is specifically licensed against BTV-8 in sheep, and Zulvac® 8 Bovis against BTV-8 in cattle.  Animals require a 2 dose primary course, with the injections given 3 weeks apart. Animals are protected 25 days after the second dose. It therefore takes just over 6 weeks from starting the vaccine course to animals being protected, and with APHA predicting an 80% risk of disease entering the UK by September, for those in high risk areas who wish to vaccination it’s important that this is done as soon as vaccine is available. Of course farmers should discuss with their vet the most appropriate control strategy for their farm.

Zulvac Bovis 8 and Ovis 8

Further information regarding Bluetongue and the Zulvac 8 vaccines can be found by clicking the button below:

Visit bluetongue website

The NFU are leading a joint action against bluetongue (JAB) campaign and as part of this have organised a series of farmer meetings details of which can be found on their webpage.

JAB

For further information APHA/DEFRA in collaboration with the Pirbright Institute have produced two useful information videos:

  1. Find out about the risk of bluetongue disease spreading into the UK here.
  2. Find out about bluetongue transmission, clinical signs & pathology here.

Additional information on how to spot and report bluetongue can be found here and further reading on monitoring for major, notifiable or new and emerging animal disease outbreaks can be found on the government website.

Zulvac 8 Bovis contains inactivated Bluetongue Virus, serotype 8.  For the active immunisation of cattle from 3 months of age for the prevention of viraemia caused by Bluetongue Virus, serotype 8. POM-V Zulvac 8 Ovis contains inactivated Bluetongue Virus, serotype 8.  For the active immunisation of sheep from 1.5 months of age for the prevention of viraemia caused by Bluetongue Virus, serotype 8. POM-V For further information please see the product’s SPC, contact your veterinary surgeon or contact Zoetis UK Limited, Walton Oaks, Dorking Road, Tadworth, Surrey KT20 7NS. www.zoetis.co.uk. Customer Support: 0845 300 8034. Use medicines responsibly (www.noah.co.uk/responsible).
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