Livestock farmers gathered in droves to air their concerns about Norfolk's growing number of bluetongue disease cases - and the restrictive "zone" now affecting animal movements.

Around 400 people crowded into Dunston Hall, south of Norwich, for an urgent meeting with Defra officials, the Animal and Plant Health Agency, and industry organisations.

Since December 8, Norfolk has recorded 13 cases of bluetongue, a potentially fatal animal disease which affects ruminants including cattle, sheep, goats, deer and camelids.

All infected cattle found within the 10km temporary control zone (TCZ) established around the initial case, found during routine surveillance on a farm near Cantley in the Broads.

Eastern Daily Press: A 10km Temporary Control Zone was set up around a farm near Cantley on December 8A 10km Temporary Control Zone was set up around a farm near Cantley on December 8 (Image: Defra)

Gordon Hickman, head of exotic disease policy at Defra, said none of the animals showed clinical symptoms, but all have been culled to stop the virus spreading.

As no animals had been imported from abroad, or moved from the other bluetongue zone in Kent, it is believed the disease was carried here by infected midges, blown across the Channel from Europe during optimum wind and temperature conditions in September or October.

In the right weather conditions and temperatures, the disease can be spread between animals by biting midges - although there is still no evidence of this in the UK. 

Eastern Daily Press: The bluetongue virus affects ruminants including cattle and sheepThe bluetongue virus affects ruminants including cattle and sheep (Image: Newsquest)

But if the virus is confirmed to be circulating in midges, Mr Hickman said an outbreak will be declared, and a much larger Restricted Zone will be enforced - typically at least 150km.

He said a "worst case scenario" would be similar to The Netherlands, where almost 6,000 cases have been confirmed. But for now, it is hoped the cold and wet weather will limit the midges' ability to transmit the virus.

Mr Hickman said: "Unfortunately we have had an unseasonably warm autumn, so the midge activity has carried on much later than usual and we have had to extend these control measures longer than we originally envisaged.

"We are trying to contain the disease and do as much as we can to stop that explosion when it warms up again in the spring, and buy ourselves some time before a vaccine is available – and that won’t be any time soon."

Questions from farmers ranged from how to protect animals in the absence of vaccines, compensation values, and a lack of designated abattoirs.

But the discussion was dominated by the movement restrictions within the Norfolk TCZ.

Specific licences are now needed to move animals out of the zone, which are only permitted where there is an "urgent and genuine welfare need”, or to go directly to slaughter at a designated abattoir.

Farmers asked how they could plan for turning out cattle from winter sheds onto grazing marshes in the spring, when future virus levels and movement restrictions cannot be predicted.

Mr Hickman said: "We will allow calves grazing to go to those marshes. What I can’t tell you now is the size of the zones in terms of being able to licence these animals back to their winter accommodation in September. That is going to be the problem.

"We have got to work together for the best interest of the livestock sector to minimise the risks of this."

Eastern Daily Press:  The bluetongue virus affects ruminants including cattle and sheep The bluetongue virus affects ruminants including cattle and sheep (Image: Denise Bradley)

Another farmer asked at what point a lack of food, bedding and housing would be considered a "welfare need" rather than a commercial decision, as owners of store cattle had planned for animals to be at different locations at different times of the year.

Mr Hickman said: "We would urge all the farmers to talk to their private vets and put in a licence application if it is a genuine welfare issue. What we won’t allow at the moment is a batch of stores going to a market because that is what you normally do at this stage.

"We are not saying never, but at the moment the risk is so high that we are not prepared to move that until we get into the 'low vector' period. That should be in the next couple of weeks, so there is some potential for that, but they will need to be tested.

"I would like to think that together we can try and find some solutions and support each other in this really difficult place. I do accept that at the moment you are taking the pain for the rest of the country."

'One infected midge can kill a sheep'

Sascha Van Helvoort, outbreak veterinary head at APHA, explained how the virus was spread by infected Culicoides midges, and the potential clinical effects on sheep and cattle.

“It is a very efficient transmission – one infected midge can actually kill a sheep," she said.

She said the midges are usually most active between April and November, and virus transmission can occur when temperatures are higher than 12C - although insects are still active above 4C.

Aled Edwards, head of field delivery for APHA, said about 45,000 livestock needed to be sampled in Norfolk and Kent - of which about 50pc have already been sampled. APHA hopes to complete testing by the end of February.

Farmers were told that all questions handed in at the meeting would be answered on Ruminant Health and Welfare’s dedicated bluetongue web page. There is also a dedicated bluetongue advice hotline on 024 7771 0386.

Defra says bluetongue does not affect human health or food safety, but livestock keepers must report suspicions of the virus immediately to the APHA on 03000 200 301.