Schmallenberg virus cases increase in Welsh lambs 8 February 2013 Last updated at 07:25 A virus that leads to birth defects in lambs is being increasingly detected in Wales, say farmers and vets. The Schmallenberg virus is carried by insects and was first detected in Germany 18 months ago. But some farmers in lowland areas of south Wales say it is now clear the disease has reached Wales. UK government officials believe there are now more than 1,200 cases of the infection in Wales and England, but they say it poses no human threat. However, it is a growing concern for Welsh sheep farmers who are becoming increasingly worried about the disease's impact on flocks. Colin Evans, who farms at Pant y Goitre farm in the Usk Valley in Monmouthshire, said between 20 and 25 lambs born to his 800 ewes appeared to have been affected by Schmallenberg - up to 5% of the flock. "There are very few [farmers] that I speak to who haven't had a case, so we understand it now and are quite concerned by it because unless we find a control for this through a vaccine, we are concerned that our 3% to 5% loss might become 20% by next year," Mr Evans said. Cattle concern Dylan Morgan, deputy director of the National Farmers' Union (NFU) Cymru, said more and more sheep farmers were likely to be affected, and there were concerns for cattle farmers too. "I think cattle is more of a worry than sheep," he said. We saw the first case, the first confirmed case, back at the end of the summer and we've certainly seen more cases in late autumn, mid-winter particularly back in December in ewes that were lambing End Quote Ifan Lloyd Vet There's nothing worse really because you've looked after that animal for the year and it comes to calving time and you've got problems, you need the vet, it adds cost, the calf is maybe deformed or dead. The disease has reached as far west as Swansea and Gower, where vet Ifan Lloyd said there had been lamb losses. But because there is no legal requirement to notify authorities about the virus, he said it is difficult to get a clear idea about how many cases are being death with in Wales. "We saw the first case, the first confirmed case, back at the end of the summer and we've certainly seen more cases in late autumn, mid-winter particularly back in December in ewes that were lambing," said Mr Lloyd. Scientists and vets fear that many farmers prefer to either keep quiet in case it harms the industry - or are simply guessing they've had Schmallenberg, with an unusually high number of lambs being born with abnormalities. A potential vaccine for the disease is currently being tested by the Veterinary Medicines Directorate, but as yet, there is no timescale for when it could be approved or introduced.