Sheep and cattle farmers are being warned that the Schmallenberg virus will spread to new counties in 2013.
Alick Simmons, DEFRA’s deputy chief veterinary officer, said farms in the south and south-east England were hit hardest by the virus this year.
But the current spell of warm weather could be helping to spread the virus to other parts of the country that have not been affected, he added.
“The Schmallenberg disease has not gone away, although it may appear that it has,” said Dr Simmons.
“We are almost certainly going to get more spread this year and we can be fairly confident that the disease will spread from the areas affected last year.
“I would be surprised if the disease is quite as bad in Kent, Surrey, Sussex and Essex (next year), but I suspect we will find the disease spreading to new areas, including Cumbria, the midlands, parts of the West Country and Wales.”
Dr Simmons said the virus was largely asymptomatic in adult sheep and new cases would only become apparent once lambing starts early next year, causing deformed or stillborn lambs.
However, cattle farmers in particular should look now for the symptoms of the disease in cows, such as fever, reduced milk yield, diarrhoea, loss of appetite, and report any suspected cases to their vets.
Dr Simmons stressed that the proportion of farms that have been affected by the Schmallenberg virus was small. “To date, there have been 274 premises in England and Wales, which is still not very many.”
But he warned that around half of the cases confirmed in April and May were from animals that got infected at the beginning of the year, which suggested that the virus could still be spreading.
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