‘Very high probability’ of a new introduction of bluetongue virus into Britain – information for small animal veterinary staff

24 May 2024

Animal and Plant Health Agency (APHA) have confirmed a very high probability of a new introduction of bluetongue virus (BTV-3) into Britain1.

Bluetongue virus affects ruminant animals such as cattle, sheep, goats and deer, and camelids such as llamas and alpacas, and is primarily transmitted via bites of infected midges (Culicoides species)1. The first case of bluetongue (BTV-3) in Britain was identified in November 2023, with a total of 126 confirmed cases in sheep and cattle in southeast England as of April 20242.

Dogs and other carnivores can become infected with bluetongue if they eat infected material such as aborted products or afterbirth, but cases are rare2.

Although the likelihood of bluetongue infection in pet dogs is currently very low, we would advise that colleagues in the southeast of England are aware of the possibility. Climate change and the increased incidence of midges carrying the virus mean that cases in ruminants are highly likely to occur in those at-risk areas.

Few cases of bluetongue infection have been reported in dogs elsewhere in Europe and other parts of the world, and cases have mostly been reported in pregnant dogs3,4,5. Clinical signs reported are dyspnoea, hypoxia, pulmonary oedema, severe emaciation, lethargy and abortion4,5,6, however some animals, particularly non-pregnant animals, may show no clinical signs6. In these reported cases, the source of infection has been suspected to be through the ingestion of ruminant aborted materials and/or afterbirth4,5, however a study of infected dogs in Morocco found the likely source of infection to be via midge bites6.

An updated qualitative risk assessment by APHA has confirmed there is a very high probability of a new introduction of BTV-3 into livestock in Britain, through infected biting midges being blown over from northern Europe, with counties on the south and east coasts of England – Norfolk, Suffolk, Essex, Kent, and Sussex – most likely to be impacted1.

References

1Defra (2024a) Bluetongue virus risk set out for the year ahead. Available at: https://www.gov.uk/government/news/bluetongue-virus-risk-set-out-for-the-year-ahead [Accessed 22 May 2024].

2APHA (2024) Risk assessment for bluetongue virus (BTV-3 and BTV-8): Risk assessment of entry into Great Britain: Qualitative Risk Assessment. Available at: https://assets.publishing.service.gov.uk/media/664dcb7eae748c43d3794018/Risk_assessment_for_entry_of_bluetongue_virus__BTV-3_and_BTV-8__into_Great_Britain.pdf [Accessed 22 May 2024].

3Spickler, AR (2023) Bluetongue. Available at:  http://www.cfsph.iastate.edu/DiseaseInfo/factsheets.php    

4Wageningen University and Research (2023) Bluetongue found in Dutch dog. Available at: https://www.wur.nl/en/research-results/research-institutes/bioveterinary-research/show-bvr/bluetongue-found-in-dutch-dog.htm

5Hanekom J, Hoepner SN, du Preez K & Leisewitz A (2022) The clinical presentation and management of a naturally occurring Bluetongue virus infection in a pregnant Rottweiler dog. Journal of the South African Veterinary Association. 93(2), http://dx.doi.org/10.36303/jsava.509 

6Oura CAL & El Harrak M (2010) Midge-transmitted bluetongue in domestic dogs. Epidemiology & Infection. 139(9), 1396 – 1400.