Welsh farmers were today urged to be vigilant following the detection of Schmallenberg Virus (SBV) antibodies in three cows and one calf on premises in Ceredigion.The Farmers’ Union of Wales described the development as very concerning. The history of the three animals suggests they were infected by SBV while on the holding, up to a year ago. FUW animal health and welfare committee chairman Catherine Nakielny said: "I would reiterate the warning we put out in January that all farmers in Wales need to be on the lookout for any unusually high incidences of abortion or congenital abnormalities - deformed lambs, swollen heads, weak lambs etc.“They should report anything unusual to their veterinarian, especially given the recent developments."The presence of SBV in Wales is not unexpected. The Animal Health Veterinary Laboratories Agency (AHVLA), the Welsh Government and the Wales Animal Health & Welfare Strategy Steering Group have kept SBV under close scrutiny since its arrival in Britain late in 2011.As of July this year, there were 275 UK farms reporting positive for SBV. Of these, 53 were in cattle, 219 in sheep and three in both. “There is a strong need to continue to monitor SBV in Wales and to this end livestock farmers should be vigilant and report suspicions to their private veterinary surgeon,” added Dr Nakielny . “SBV is not currently a notifiable disease in the UK but farmer’s need to remember that test samples taken from suspect animals will still be paid for by Government for the time being.” It remains possible that midges could continue to spread SBV in Britain through the autumn and into the winter but the FUW hopes the poor weather which has blighted the industry over the summer has reduced the risks of transmission.There is no known risk to human health from SBV but the advice for pregnant women remains to be cautious around farm animals and to follow strict hygiene procedures, the union has stressed.Advice to farmers is to make use of two AHVLA programmes of enhanced surveillance for foetal deformities and for acute SBV disease in cattle. FUW members wishing to know more about these programmes should contact their county office.“Advice from the AHVLA for possible actions to reduce the impact of Schmallenberg virus in sheep flocks is to delaying tupping until midge activity is reduced, delaying breeding from ewe lambs until 2013,” said Dr Nakielny. Immunity may have then developed by the 2013 tupping season either by exposure to infected midges or through the use of vaccine, if such becomes available.Farmers are also advised to use products which repel or control biting insects prior to tupping and in early pregnancy. The likely benefit of these products is uncertain particularly as midges are widespread and appear to be particularly effective in transmitting the virus. Other measures such as housing ewes, and removing muck heaps to deny breeding habitats from the vicinity of housed sheep may help to reduce midge exposure.Many aspects of this virus remain unknown and there is currently no vaccine or treatment available. SBV research and surveillance remains ongoing and the FUW will continue to monitor the scientific and technical developments relating to this virus.