NSA Briefing on the discovery of Schmallenberg virus in England

26th March 2012


It is  most likely that the infection was transmitted by insects during the late summer/autumn of last year and the risk of further infection being transmitted from these farms is low.  There are currently no implications to trade and no ‘firewall movement barriers’ being put in place in the UK, although Russia has put in place export bans on live ruminants and ruminant products from the Netherlands, Belgium and Germany, where Schmallenberg virus has been present for some time.

Guidance for sheep producers

Official veterinary advice is two-fold at the moment; Farmers are strongly encouraged to support the gathering of information and report any suspicions of Schmallenberg to their veterinary practice (see below for clinical symptoms), and secondly any imports of live animals from EU regions affected by Schmallenberg virus should be undertaken in strict consultation with veterinary advice and guidance.

The clinical symptoms in sheep include late abortion and birth defects/malformed foetuses and the NSA would encourage any sheep keepers that experience such occurrences to speak to their vets and consider post mortem testing.  Producers in Scotland should also contact SAC Veterinary Services, and those in Wales and Northern Ireland their Government veterinary departments.

Schmallenberg virus also affects cattle with symptoms including fever, milk yield reduction, and diarrhoea. Defra have indicated that they will cover the costs of testing for Schmallenberg virus although post mortem costs will be at the farmers cost.  There is currently no vaccine available to protect against Schmallenberg virus, vaccine manufacturers and laboratories are currently considering whether it would be possible and effective to develop a vaccine but estimates are that such a vaccine would be at least 2 years away.  It is expected that animals that have been infected with Schmallenberg virus will develop immunity and production is likely not to suffer in subsequent years – however if experienced it could affect individual flocks seriously.  


It may seem that there is little that farmers can do to protect their flocks, and in terms of vaccine protection this is true.  However there are things that farmers can and should do and these include:

  • Support the gathering of information and reporting by speaking with their vet regarding any abnormalities in fertility, abortion, or lamb malformations
  • Take veterinary advice before importing any animals from areas affected by Schmallenberg virus (details can be found on the defra web link below).  The NSA would discourage any imports of live animals from these regions.
  • Remember that the virus can be transmitted during periods when insect activity is evident – but that clinical signs may not be seen until later in the season.  Consequently always assess the risks of bringing stock onto your farm.  
  • Always practice the highest possible levels of general biosecurity and quarantine/separation whenever bringing new animals on site.
  • Manage your stock to promote general health and vitality.  This can be helped by good nutrition including optimum mineral and trace element levels, and through managing internal and external parasites.  Given that there is no vaccine available do all you can to increase the ability of your flock to cope with disease challenges.

For more information please follow this link to the defra web site www.defra.gov.uk/animal-diseases/files/poa-schmallenburg-update-120117.pdf (note the alternative spelling – both versions are being used).

The NSA will continue to keep you informed of any developments via our web site, our regular e newsletter, and the Sheep Farmer magazine.  If you do not receive the e newsletter and would like to please email membership@nationalsheep.org.uk with your membership number, to be added to the list of recipients.