Bluetongue: Surveillance & control

Control strategy

Government is working closely with a core group of industry stakeholders to decide on actions necessary to combat Bluetongue disease. To this end a policy statement and supporting rationale and economic assessment has been agreed . This sets out the strategy and priorities for the winter period. The UK remains committed to a disease control approach which aims to contain disease within the current restricted zones.

Defra has been working in partnership with the farming industry and Devolved Administrations to revise the UK Bluetongue Control Strategy. The revised Strategy reflects lessons learned since its original publication in August 2007, addresses new risks, and reflects the developing situation in continental Europe and associated risks of incursion by new serotypes. 

The measures set out in legislation are aimed at preventing disease spread through, for example, restriction of animal movement and through vector control measures. Broadly, the controls can be summarised as follows:

    • Veterinary investigation on suspect premises, and restrictions which includes a ban on movement of susceptible animals on and off the premises.
    • On confirmation that bluetongue virus is circulating, a Restricted Zone (RZ) will be declared around the infected premises. The RZ may consist of:
      • A Protection Zone (PZ) (at least 100km radius around an IP) and a Surveillance Zone (SZ) (at least 50km in radius beyond the PZ); together they are called the Bluetongue Restricted Zone.
    • There is some flexibility in demarcating the Bluetongue Zones (with Commission agreement), but various factors such as local geography must be taken into account. The size of the Bluetongue Zones in England is based on EU legislation for the control of the disease and veterinary risk assessment.

The vector-borne nature of the disease (and distribution of vectors) ensures that the risk of disease spread can only be controlled to a limited degree (i.e. we cannot guarantee 100% protection from vectors).

The benefits of housing animals at times of the day when the midge vector is most active are unproven (at least in the context of species of midges transmitting BTV8 in Northern Europe). Treatment of midge breeding grounds e.g. manure heaps as well as using repellents and approved pour-on insecticides on cattle and sheep may reduce the risk of infection to some degree in certain circumstances.

In partnership with industry, we will be issuing guidance on the likely effectiveness of such measures. It is also important to avoid using contaminated surgical instruments or hypodermic needles on livestock.

As Bluetongue is spread via vectors (i.e. midges), rather than from animal to animal, compulsory slaughter of ruminants infected with bluetongue would not normally form part of our control strategy.

Surveillance

We have two ongoing means of detecting Bluetongue in GB.

  • There is a legal requirement for livestock holders to report all cases of Bluetongue infection on their premises. This allows us to assess any new midge-transmission from the continent or re-emergence of disease. 
  • Every susceptible animal imported from continental Europe is currently post import tested for all serotypes of Bluetongue.

March 2009

A one off bulk milk testing surveillance exercise was targeted at a selection of unvaccinated dairy herds across five areas of GB.

There has been no evidence of circulating Bluetongue in 2008 or 2009 and the negative results of this March’s surveillance exercise provide us with further assurance that we do not have circulating Bluetongue in GB.

Winter Surveillance

The survey will take place across the whole of GB, starting from 1 November and running for approximately one month. It will enable us to get a clearer picture of the BTV8 disease situation, and to detect any potential incursion of new serotypes.

The survey will test for all Bluetongue serotypes including BTV1 which is currently circulating in France.  

The results of the survey will be used to plan our future policy and any additional surveillance in 2010. Should the results of our winter surveillance show that there is no circulating virus, it will also take us a step closer to being able to consider officially declaring freedom from disease at some point in the future.

However it is important that livestock keepers continue to report suspicion of Bluetongue as this remains a legal requirement and is a key element of our surveillance. It is also crucial to continue to vaccinate against BTV8 as this is our best defence against the disease.

Legislation

Commission Regulation of 26 October 2007 on the control, monitoring, surveillance and movement restrictions of certain animals susceptible to Bluetongue (PDF 97 KB - Link to the EU website).

The Bluetongue Order 2007 implements Council Directive 2000/75/EEC concerning the control and eradication of Bluetongue.

Page last modified: 26 October, 2009