Bluetongue cases surge as vets warn of severe season

Rapidly rising numbers of bluetongue cases (BTV-3) have sparked growing concern among vets and industry leaders, who say this year’s outbreak is proving far more severe than previous seasons.

Speaking at the National Sheep Association (NSA) Sheep Event in Malvern on Tuesday (28 July), Sheep Vet Society president Phillipa Page said sheep were showing more severe clinical signs, and a greater proportion of animals were being affected by BTV-3.

See also: Bluetongue cases rise as farmers urged to stay alert

“Compared to the previous two years, the signs that we’re seeing in sheep this year are much more severe,” she said.

“Where we may have seen one or two animals affected clinically in flocks, this year we’ve seen up to 10-20% of animals in those individual flocks affected.”

Although official figures last week recorded 24 confirmed cases in England and Wales, Ms Page said the published total represented “the tip of the iceberg” because of delays between clinical signs appearing and laboratory confirmation.

She added that colleagues in the South West had visited as many as 20-30 farms last weekend, highlighting the scale of the outbreak.

Weather driving transmission

Unlike previous years, she said forecasting disease spread had become more difficult because the virus had successfully overwintered in the UK rather than arriving in infected midges blown across from mainland Europe.

National Beef Association chief executive Neil Shand urged livestock keepers not to delay vaccination, warning that hot, dry conditions were helping drive transmission.

“People really need to wake up to the challenge of this disease, which has overwintered in the country, and the summer is giving the disease a reservoir for growth,” he said.

Mr Shand warned farmers not to dismiss poor fertility as a consequence of the weather alone and urged producers who decide not to vaccinate this year to ensure their herds are protected before next season.

Industry collaboration

NSA chief executive Phil Stocker praised the collaboration between industry, Defra and the Animal and Plant Health Agency (Apha).

“This has been a really good example of industry and Defra and Apha and others working really well together to try to reduce the risks and overcome some of the problems we’ve got,” he said.

Farmers are reminded that bluetongue vaccination provides protection for up to 12 months, with booster doses extending immunity.