10/01/2012Posted : January 10, 2012
UK farm vets urged to remain vigilant for signs of new virus

The BVA is urging farm vets and farmers to familiarise themselves with the clinical signs of the newly discovered Schmallenberg virus, particularly on farms where animals have been imported from affected countries.

The virus, of the genus Orthobunyavirus, was initially detected in cattle in Germany and, based on the geographic origin of the sample, was provisionally named Schmallenberg virus (SBV). Since the summer of 2011, clinical signs have also been reported on farms in the Netherlands.

Clinical signs include:

• fever,
  
• reduced milk yield (up to 50%),
  
• inappetence,
  
• loss of condition and, in some cases,
  
• diarrhoea.

Clinical signs are generally mild and disappear after a few days but, where pregnant animals are infected, considerable congenital damages, premature births and reproductive disorders may occur.

Since DEFRA's final report of 2011, Belgium has reported finding viruspositive lambs with congenital deformities on 11 sheep farms in the North Western region of Antwerp, as well as deformities in a further eight cattle, three more sheep and on one goat farm.

With this in mind, and although no clinical signs or neonatal deformities have been reported in the UK, both DEFRA and the BVA are urging animal keepers to remain vigilant, particularly in areas where consignments of cattle that originated in the affected regions were moved to the UK during July – November 2011 (see map below).

BVA president Carl Padgett said: "Farmers and vets should be extra vigilant where ruminants have been imported from the affected areas. The symptoms described in adults are quite generic but this disease seems to affect a few animals, not just one."

He went on: "AHVLA is now looking for reports of signs in newborn ruminants and aborted foetuses of limb or brain defects such as arthrogryposis, jaw deformations and torticollis, and ataxia, paralysis and blindness. They are particularly interested if these offspring were born to animals where there is a history of importation from the infected areas in northern Europe."

With information on the virus constantly being updated, the BVA strongly advises that vets and farmers keep up to date via the DEFRA website, while reporting any suspect signs to the local AHVLA or SAC laboratory.

Mr Padgett concluded: "Although the risk of transmission to humans is considered very low it cannot be excluded and we recommend farmers and vets take all sensible precautions to prevent infection."