This week animal health chiefs predicted the resurgence of Schmallenberg following its prevalence in 2012/13, as new cases were reported across the UK.
AHDB Dairy’s lead veterinary science expert Derek Armstrong said the UK was particularly at risk from Schmallenberg (SBV) due to its ’sandwich position’ between Ireland and the Netherlands-Belgium border, where there have been a number of confirmed reports.
Cases have already been confirmed by the Animal and Plant Health Agency (APHA) in Devon, Dorset, Cornwall, Somerset, Co Laios and Co Cork, with more instances arising in Worcester, Gloucester, Pembrokeshire, Cheshire, Northampton and Carmarthenshire.
SBV causes major abnormalities in new-born animals, including birth defects and twisted limbs in lambs and calves. It can also cause adult sheep to have early abortions.
It came as bird flu continued to spread across the UK.
"It is expected SBV will be found in the later lambing season," Mr Armstrong said. "Milder weather conditions earlier in November were a perfect platform for the midge-borne virus to breed and prolong the period of infection."
He said while a vaccine had been formulated, it was not licensed in the UK.
But farmers have been urged to take suspected SBV-infected lambs and calves for testing at a veterinary investigation (VI) centre, to encourage pharmaceutical companies to produce the vaccine and gain a license for use in next year’s lambs.
The National Sheep Association (NSA) said despite circulation of more suspected cases, the 'true picture of the problem' could not be found until incidents were confirmed by post-mortem.
An APHA spokesperson said: “Advice to farmers is that Schmallenberg virus (SBV) remains a threat in 2017 and vigilance should be maintained for signs of fever and milk drop in dairy cows and for deformed lambs and calves.
“Vets can advise on how best to manage the risk on farms, including making business decisions about diagnostic testing to confirm presence of disease.”