Bluetongue is a notifiable insect-borne viral disease that affects all ruminants, such as cattle, goats, deer and more severely sheep. It cannot be spread directly between animals and relies on the midge as a vector for transmission.
The disease does not affect humans and there are no public health or food safety implications.
On this page: Current situation Clinical signs Biosecurity guidance Control Strategy Vaccination Relevant Legislation Frequently Asked Questions
Great Britain is officially a free area from bluetongue. The last outbreak in Great Britain was in 2007.
Post-import checks are carried out routinely by APHA (Animal and Plant Health Agency) and immediate action will be taken in response to any non-negative results, in order to prevent spread of disease. Further information about this process and the recent (October 2017) detection of the virus in post-import tests in Scotland can be found in our FAQ section.
The Bluetongue situation in the EU has considerably changed in recent times with incursions of new serotypes, namely of serotype 8 (in an area of the EU where outbreaks have never been reported before and which was not considered at risk of bluetongue) and also of serotype 1 of that virus on southern Europe.
Defra have published a detailed assessment of the risk of bluetongue virus (BTV-8) entry into the UK and will keep this under review. In view of the latest disease intelligence, suitable weather over Europe, considerable midge activity, short virus replication rates, the overall risk level for the UK is "low".
Animal keepers should be very vigilant for any signs of notifiable disease and report any suspected cases to APHA immediately. When importing animals into Scotland, animal keepers should ensure they consider the risks carefully and check the health status of the animals. Animal keepers should also consult their vet on other measures, such as protective vaccination.
An updated map showing the location of current EU restriction zones can be found on the following webpage - Bluetongue - European Commission
Infection with bluetongue can significantly compromise livestock welfare, both in terms of unpleasant symptoms and a potentially high mortality rate (around 30%). Animals can recover from the disease. Such animals become immune to the strain with which they were infected and, after around 60 days, they stop shedding virus into the bloodstream, meaning that they no longer pose a risk in terms of onward infection of the midge population. However, there are long terms impacts on productivity and fertility.
The clinical signs are more apparent in sheep, than other ruminants, and can include:
- swelling of the head and neck
- inflammation and ulceration of the mucous membrane of the mouth, nose and eyelids
- loss of muscle tone and weakness
- haemorrhages in the skin and other tissues
- respiratory signs such as froth in the lungs and an inability to swallow and discolouration; swelling of the tongue.
Although bluetongue usually causes no apparent illness in cattle or goats, cattle may display clinical signs including:
- nasal discharge
- swelling and ulceration of the mouth
- swollen teats
As with any notifiable disease, if you suspect that your livestock may be infected with bluetongue, you must contact your local Animal & Plant Health Agency (APHA)
How Bluetongue is spread
Midges carry the bluetongue virus. The disease spreads when infected midges bite an animal affected by the disease. The midge season is normally March to September. The weather (especially temperature and wind direction) affects how the disease can spread.
As bluetongue is only transmitted via an insect vector (midge) additional cleaning and disinfection is not required, other than that routinely used as protection against infection from other diseases. However there are other biosecurity precautions that you can take:
- Be vigilant. Be aware of the clinical signs of bluetongue and inspect your livestock regularly. If you suspect the presence of the disease, contact your local Animal Health Office immediately.
- Be cautious when sourcing replacement livestock. Where possible, avoid importing livestock either originating in or transiting bluetongue Restricted Zones. Where this is not possible, ensure that livestock are symptom free before arriving, find out if they have been vaccinated and protected with insecticide whilst travelling.
Use of Insecticides
A list of Health and Safety Executive ( HSE) authorised insecticides for use against flying insects in animal housings or similar areas such as abattoirs can be found via the links below. Please pay particular attention to the guidance notes. If in doubt please contact your local SEPA office.
Insecticides licensed by the Health and Safety Executive
The GB Bluetongue Virus Disease Control Strategy sets out the disease control measures we would consider if bluetongue virus was suspected or confirmed in farmed ruminants (including cattle and sheep).
The measures to control and eradicate the disease include vector control, (use of insecticides in the animal premises and in the areas where these insects live, insect repellents onto animals, mosquitoes nets, etc.), restriction to movements of live ruminants from affected areas to non-infected regions where the vector is present and the use of vaccines.
Zones and Movement Controls
Following confirmation of circulating bluetongue virus, we are required to declare a Restricted Zone (RZ) around the Infected Premises (IP). The RZ will comprise:-
- A Control Zone (CZ) around the IP with a minimum 20km radius;
- A Protection Zone (PZ) with a minimum 100km radius; and
- A Surveillance Zone (SZ) a further 50km beyond the PZ.
It is important to note that the zone sizes above are the minimum requirements. We have the flexibility to declare larger zones. In determining the zone sizes and shape, we will need to consider a wide range of factors including risks, impacts, geographical barriers and time of year.
Restrictions are placed on movements of susceptible animals out of these zones and some may be permitted under licence. More detailed information about movement restrictions during an outbreak is provided in the GB Bluetongue Virus Disease Control Strategy. This page will be updated if zones are declared.
Trade, Import and Export
No specific restrictions currently apply. The most important defence for Scotland is for the livestock industry to avoid sourcing livestock from high-risk areas and to ensure that they know the health and vaccination status of any animals brought into Scotland.
The APHA Centre for International Trade (CIT) Carlisle should be contacted for advice about imports and exports to and from Great Britain.
General enquiries email: CentralOps.Carlisle@apha.gsi.gov.uk
Telephone: 03000 200 301
Fax: 0208 0260 498
Further contact details - team contact detail
Vaccination against bluetongue is permitted. The declaration allowing voluntary vaccination is made under The Bluetongue (Scotland) Order 2012. In making this declaration, the Scottish Ministers have completed a specific risk assessment, as required under EU Legislation. Only vaccination using an inactivated vaccine is permitted. Vaccination against the disease is effective and helps to reduce the spread of infection.
Culling and Compensation
If infection is confirmed on a premises and there appears to be limited local spread e.g. on the farm and no evidence of widespread circulation of disease by midges, Scottish Government is likely to try and contain and eradicate it by culling relevant ruminant animals. Compensation would be paid for animals destroyed for the purpose of disease control and diagnosis, unless they are slaughtered because of non-compliance with import requirements. Once BTV is in the midge population, the culling of susceptible animals is unlikely to be a proportionate or effective control measure.
Powers for the control of bluetongue are laid out in:
- The European Commission Directive 2000/75/EC as amended, laying down specific provisions for the control and eradication of bluetongue
- The Commission Regulation (EC) No. 1266/2007 as amended, on protection and surveillance zones in relation to bluetongue and conditions applying to movements from or through these zones (updated as new outbreaks occur and as new information on control methods arises).
- The Bluetongue (Scotland) Order 2012, lays out how European rules on bluetongue are implemented in Scotland.
- The following Declaration is made under The Bluetongue (Scotland) Order 2012: Declaration of area in which voluntary vaccination against bluetongue is permitted.
Further advice and guidance
JAB. Bluetongue Guidance for GB Livestock Keepers http://www.nfuonline.com/assets/63528
A full list of disinfectants and dilutions approved for use can be found in The Diseases of Animals (Approved Disinfectants) Amendment (Scotland) Order2006
NFU have produced a leaflet and poster on Bluetongue.
APHA have produced a video which provides information about the clinical signs of Bluetongue.