Schmallenberg virus (SBV) was first identified in 2011 and the disease subsequently spread widely throughout Europe. During the 2012 and 2013 lambing and calving seasons, there were numerous cases of congenital defects in lambs and calves. This was due to in-utero exposure to SBV in UK flocks and herds.
In the summer of 2016, Schmallenberg virus re-emerged. This resulted in the birth of typically affected lambs and calves the following year.
There is a recognized pattern of 3-5 year cycles with endemically established viral vector borne (arbovirus) diseases. This pattern suggested the possibility of another wave of infection, which would manifest itself this lambing and calving season. PCR testing in lambs and a calf has already detected SBV at four post-mortem centres.
Following on from the announced enhanced surveillance for SBV in small ruminants, APHA will also offer to test cattle samples free of charge. A fresh brain sample will be tested from calves with arthrogryposis and/or spinal defects.
Since the detection of the virus in the fetal brain depends on the stage of gestation when the fetus became infected, a negative PCR test would not rule out in utero infection. As such, serum samples can also be submitted from up to six cows/heifers. This includes any that have aborted a calf (particularly those with the gross pathology described above), so that they can also test these to detect antibodies to SBV in the dam.
Please contact us if you’d like to discuss this further, or if you have any concerns about Schmallenberg on your farm.
You can read more about the virus here.