June 27, 2024

 

Veterinary professionals warn of bluetongue and ASF threats to UK livestock

Veterinary professionals have identified diseases such as bluetongue and African swine fever (ASF) as potential risks to UK livestock this summer, Farmers Weekly reported.

 

The presence of these diseases in UK herds could negatively impact export trade to certain global markets.

 

Speaking at AHDB's Red Meat Export Conference, UK Chief Veterinary Officer Christine Middlemiss indicated that warmer weather could result in more infected midges carrying bluetongue crossing over from Europe.

 

Bluetongue was first confirmed in England last November from infected midges believed to have blown over from the Netherlands.

 

Dr Middlemiss noted that the Netherlands had recorded clinical signs with sick and dying animals. However, there had not yet been any clinical cases in the UK, with all confirmed cases found through surveillance of animals that appeared to be well.

 

"We are working very closely with vaccine manufacturers," she said. "It's good that they are now vaccinating in the Netherlands. That should reduce our risk a bit."

 

She added that the industry was working to get a dossier of information approved by the end of the year, though it would not be in time to stop the disease spreading this year.

 

Like bluetongue, cases of Schmallenberg have been more prevalent this year. A vaccine is available for Schmallenberg in the UK, but manufacturing had stopped due to the lack of prior demand.

 

The UK remains at medium risk for ASF, which continues to spread in wild boar in Europe, according to Dr Middlemiss.

 

Human-mediated transmission poses a higher risk, as it allows for longer jumps between countries.

 

Dr Middlemiss stated that until a vaccine is available in the UK, the risk status would not change.

 

However, significant research is underway to find a vaccine, led by organisations such as the Pirbright Institute.

 

"There are vaccines people hear about being used in Asia, and they are helpful there because they are suppressing the disease," she said.

 

"When you have 80% of your swine population on farms infected and when you are so reliant on pork for domestic consumption, there is some benefit from suppression. But they are not vaccines that would help stamp out and get rid of the virus, and that is what we in the western world are looking for."

 

The UK is currently classed as a "controlled risk" country for Bovine Spongiform Encephalopathy (BSE); however, the industry is pushing for this to be downgraded to "negligible risk" status.

 

Dr Middlemiss mentioned that despite a case of BSE being reported in Scotland last year, the UK can apply for negligible status because all the necessary controls are in place.

 

A case is due to be submitted to the World Organisation for Animal Health in a few months' time to move the UK to negligible risk, and it is set to be voted on in May 2025.

 

Cases of avian influenza on US dairy farms have impacted trade, with Colombia recently banning imports from some US states as a result.

 

Dr Middlemiss noted that the mixed strain currently seen in the US includes both high-pathological and low-pathological strains.

 

She explained that most transmission on US farms is mechanical, such as through equipment in dairy parlours. She also noted that pasteurisation kills the virus, so the risk of it arriving in the UK in dairy products is very low.

 

The incidence rates of bovine TB in higher-risk areas have fallen by about 7%, according to Dr Middlemiss.

 

She attributed the fall to a combination of increased cattle controls, skin testing and gamma testing, and the badger cull.

 

-      Farmers Weekly