Updated:13/09/2024

Latest bluetongue virus update

This page will be updated regularly with resources and information – for any queries email RuminantHW@ahdb.org.uk 

Latest update 12 September 2024

Following a report of clinical suspicion in sheep near Faversham in Kent, BTV-3 has been confirmed. In accordance with the disease control framework, a 20km temporary control zone has been declared.

Three further cases were identified through surveillance testing in Essex in the current Restricted Zone, and one further case was identified through surveillance testing in East Yorkshire in the current Temporary Control Zone. No changes in these zones are necessary.

This brings the total number of premises affected to 46.

Recent BTV-3 updates

BTV-3 update 11/9/24

Following surveillance within the temporary control zone in North East Lincolnshire, 2 further cases of BTV-3 was detected. In accordance with the disease control framework, the temporary control zone has been further extended.

One further case was identified through surveillance testing in Essex in the current Restricted Zone. No changes in this zone are necessary.

This brings the total number of premises affected to 41.

BTV-3 update 10/9/24

Following surveillance within the temporary control zone in North East Lincolnshire, a case of BTV-3 was detected. In accordance with the disease control framework, the temporary control zone has been extended.

Following reports of suspicion in cattle and sheep, the chief veterinary officer confirmed the presence of bluetongue serotype 3 (BTV-3) on 2 new premises in the Restricted Zone on 10 September. One further case was identified through surveillance testing in the zone.

BTV-3 update 8/9/24

Following reports of suspicion in cattle and sheep, the chief veterinary officer confirmed the presence of bluetongue serotype 3 (BTV-3) on 3 new premises in the Restricted Zone on 8 September. One further case was identified through surveillance testing in the zone. This brings the total number of premises affected to 34.

View all the BTV-3 updates here: 

Advice for farmers

RH&W’s advice to farmers and their vets remains three-fold, farmers need to beware when buying animals in, take action to report any signs, and always, remain vigilant:

  1. Buyer beware, source animals from Europe responsibly and request pre-movement testing.
  2. Take action, prioritise biosecurity and report any suspicious clinical signs.
  3. Vigilance is key, monitor livestock closely.

To ‘act’ on BTV-3, be aware of how bluetongue is transmitted as a vector-borne disease, take caution against misinformation, and promote evidence-based tactics on-farm.

  1. Awareness of how BTV-3 is transmitted as a vector-borne disease
  2. Caution against any misinformation, but instead view the latest facts
  3. Tactics on-farm to help with midge control must be evidence-based

BTV-3 detection update – August 2024

Detection of evidence of disease/exposure to a virus usually falls into two categories:

  1. Looking for the virus itself (antigen testing).
  2. Looking for an animal’s response to the virus (antibody testing). Both natural infection and vaccination should result in a positive test for antibodies.

There are different samples that can be collected for these tests. Most commonly a blood test, but other samples such as swabs, urine or bulk milk samples from a dairy herd, can also be used to detect both virus and antibody with varying degrees of success. The best sample to take to be certain of infection, and the timing of sample collection, is dependent on the virus we are working with.

There are three main reasons why bulk milk testing is not suitable for early detection of BTV-3 in England.

1.1. The BTV-3 bulk milk ELISA is not very sensitive for early detection application. The sensitivity of the test is 54% when the herd prevalence is <2%. Herd prevalence is likely to be low at the start of an outbreak, so only having a sensitivity of 54% will mean close to half of antibody positive animals will be missed. Even in a more widespread outbreak where the herd prevalence is 4%, the sensitivity is 85%, which is still relatively low. Ideally a test would have a sensitivity of 100% (meaning it would not miss any antibody positive animals). With sensitivity below 100%,  animals that have been exposed to the virus may not be detected (false negatives) by the bulk milk sample ELISA test. In early surveillance, this would be detrimental to any control plan.

1.2 There is a risk of vaccinated (but not infected) animals being detected. This would cause significant inconvenience for affected farms.

  1. Animals imported from a BTV positive country must be vaccinated before entry to the UK. In 2016, a survey showed that there were a significant number of vaccinated cattle in the UK. If these are detected on surveillance testing, a full BTV investigation, together with movement restrictions would potentially be conducted.
  2. There is a possibility that some animals that were vaccinated or infected during the previous BTV-8 outbreak are still alive. The test cannot distinguish a response to BTV-3 from BTV-8.

1.3 Bulk milk testing is not suitable to detect the BTV-3 itself, the current test is to detect antibodies against it. BTV is associated with red blood cells and hence is very difficult to detect in other samples such as urine or milk where red blood cell content is low. While PCRs tend to be extremely sensitive in detecting BTV (i.e., they will pick up virus if it is there), this is not the case for BTV in milk.

Bulk milk testing is relatively quick, easy and cheap and it does not require blood samples to be taken. The Netherlands did use this method in the early stages of the outbreak to determine whether they had had earlier infections that they had not been detected clinically or by PCR. While this testing did identify some antibody positive bulk milk samples, they could not determine if these were previously infected or vaccinated animals (to other BTV serotypes like BTV-8 or BTV-4) which did result in full investigations. However, it was useful to give an indication of how far the virus had spread throughout the country.

In conclusion, in an early outbreak situation, prevalence is likely to be less than 2% and therefore a sensitive test is required. The current BTV bulk milk ELISA is not sensitive enough (54%) to provide useful data. As the virus is associated with red blood cells , there is little virus, if any, found in milk. Therefore, if we want to detect virus, blood samples need to be collected for PCR.

In England, early detection sampling for BTV-3 will be performed by strategic blood testing for virus detection (by PCR).

Bluetongue is a notifiable animal disease. If you suspect it you must report it immediately by calling the Defra Rural Services Helpline on 03000 200 301. In Wales, contact 0300 303 8268. In Scotland, contact your local Field Services Office. Failure to do so is an offence.

APHA interactive BTV-3 map 

Click to view the APHA interactive BTV map

Additional Resources

What is bluetongue?

Bluetongue (BTV) is a viral disease transmitted by biting midges, which affects all ruminants (e.g. sheep, cattle, goats and deer) and camelids (e.g. llama and alpaca). 

The latest strain, BTV-3 appear to mimic BTV-8 in its behaviour, however the existing BTV-8 serotype vaccine will not offer cross protection against this new strain.

Bluetongue movement licenses and designated slaughterhouses

Temporary Control Zones (TCZs) and Restricted Zones (RZ) are now in place following the localised outbreak of the disease beginning in August 2024.

Movement of animals in these zones is likely to risk causing more spread of the virus – think before you move.

 If it is essential for you to move animals please observe the following information on licensing.

Licence overview
There are two types of licence required for movement of animals:  

  1. General Licence
    Please check carefully that the general licence applies to you and the movement you are making before moving any animals and that you comply by the conditions of that licence. A copy should accompany any animals moved under a general licence. You do not need Defra approval to use a general licence.
  1. Specific licence
     This covers any movement or activity within any current disease control zones that are not covered by a general licence. These licenses need Defra approval before the movement can be authorized.

Please view the live APHA interactive bluetongue virus map to find the latest RZ and TCZ information.

For all animal movements, prepare and have your movement licenses to hand.

Licensing advice:

  • Please allow 5 days or more for any licence application to be processed given that complex and high-risk movements will need extra time to process.
  • Contingency planning will be required to allow for the licenses to be issued.
  • Plan for what steps you will need to take if the license is refused or your application cannot be met in time.

Please note if a specific license is issued, it will usually only be for a one off movement based on disease control risk.

  1. If premovement testing is required, the following steps are to be taken:
  2. Keeper arranges with their private veterinary surgeon to take 1x EDTA blood sample (purple top tube) and 1x plain blood sample (red top tube) from each animal.
  3. The veterinary surgeon will complete a sample submission form, available on the Pirbright website.
  4. On the sample submission form, the veterinary surgeon is to select both options for RT-PCR testing for bluetongue virus.
  5. The veterinary surgeon is to write in the additional information section of the sample submission form that this submission is for (specify as appropriate) pre-/post- movement testing.
  6. The veterinary surgeon is to package the sample in a way that prevents leaking.
  7. The veterinary surgeon will send the package by Royal Mail, ideally through next day delivery, addressing it to: NVRL, The Pirbright Institute, Ash Road, Pirbright, Woking, GU24 0NF
  8. Pirbright will complete the PCR tests for bluetongue and will send the results by email to the veterinary surgeon and the APHA licencing team. Results are usually returned within a week.

BTV-3 events and webinars

Date Time Details Location For who?
Tue 19 Dec 2023
Available on-demand
Online
Vet only
Wed 20 Dec 2023
Available for members
Online
NFU Members only
Wed 20 Dec 2023
Available on-demand
Online
Farmers, vets and industry
Wed 10 Jan 2024
Available on demand
Online
Vets, industry and farmers
Mon 15 Jan 2024
7.00pm-8.30pm
Dunston Hall Hotel, Norfolk, NR14 8PQ
Farmers and vets
Wed 24 Jan 2024
Available on-demand
Online
Vets, industry and farmers
Wed 7 Feb 2024
Available on-demand
Online
Vets, industry and farmers
Wed 21 Feb 2024
Available on-demand
Online
Vets, industry and farmers
Wed 6 March 2024
Available on-demand
Online
Vets, industry and farmers
Thurs 25th April 2024
Available on-demand
Online
Veterinary professionals
Wed 1st May 2024
Available on-demand
Online
Vets, industry and farmers
Wed 15th May 2024
Available on-demand
Online
Vets, industry and farmers
Wed 12th June 2024
Available on demand
Online
Vets, industry and farmers
Wed 10th July 2024
Available on-demand
Online
Vets, industry and farmers
Wed 7 Aug 2024
Available on demand
Online
Vets, industry and farmers
Thurs 22 Aug 2024
Available on demand
Online
Vets, industry and farmers
Wed 4 Sept 2024
Available on demand
Online
Vets, industry and farmers
Wed 11 Sept 2024
Available on demand
Online
Vets, industry and farmers
Wed 18 Sept 2024
5-6 pm
Online
Vets, industry and farmers
Wed 25 Sept 2024
5-6 pm
Online
Vets, industry and farmers

Bluetongue prevention Q&A

Ruminant Health & Welfare and AHDB has brought together experts right across the four nations, including scientists, research and veterinary professionals to ensure the following information is available for farmers.

BTV is transmitted by Culicoides biting midges. These are the smallest blood feeding insects; 2-4mm long and are hugely abundant.

 

Midges breed in damp organic matter such as soil, leaf litter, compost, and animal dung (different to mosquitos who breed in water such as ponds)

An uninfected adult midge bites an infected ruminant animal taking in blood and therefore taking in the virus. The virus replicates within the insect (4-20 days depending on air temperature) and moves to the salivary glands. The infected adult midge then bites an uninfected ruminant, transmitting the virus. A single bite from a single infected midge is sufficient to reliably transmit the virus. This ruminant animal will be infectious within 2-4 days.

A single bite from a single infected midge will reliably transmit the virus. Additional bites will not result in greater levels of infection or worse clinical signs.

BTV transmission is seasonal because midges are seasonal. Culicoides midges are active in Northern Europe between April and November with peaks in May and September due to temperature.

Midges are most active at dusk and dawn. Their activity is strongly influenced by the weather. Midges are not able to fly in high winds or rain. Average daily temperatures need to be above 15 degrees Celsius for BTV to replicate within the midges.

There is no way of protecting all livestock from being bitten by midges. Use wind to your advantage as midges cannot fly in high winds.

There is no evidence that insecticides (applied to the animal) can kill midges fast enough to prevent the first bite and will not prevent onward transmission of bluetongue. There are no products licensed for Culicoides ‘control’. Residual spraying of insecticides around your farm would present a significant environmental risk to all other insects.

There is no evidence that insect repellents prevent onward transmission of bluetongue virus. Repellents have very short retention/efficacy times, especially in the rain. Any products claiming medicinal effects are doing so illegally.

Midge traps are used in midge monitoring, but they are not effective at reducing midge population size.

Midge nets on buildings were used in The Netherlands, however, it was thought that air movement above the animals (at a speed of >3m/s) was more important in preventing the midges coming into contact with livestock than the nets themselves. ‘Midge nets’ available to purchase often do not have small enough aperture for Culicoides midges (less than 0.5mm aperture) and are very costly.

Effectively screening a whole barn could be practically challenging. Housing animals during a hot summer could have welfare implications if air flow is insufficient.

No. Midges breed in a wide range of habitats. If you remove or cover dung heaps, they will find alternative.

Midges do not like wind or rain. Take advantage of windy, high, colder grazing areas.

Good biosecurity is the best method of control, i.e. keeping trailers clean. Avoid moving during dawn and dusk when midge biting activity is highest. Movement restrictions are the best method of reducing disease transmission during an outbreak.

  • How far a midge can fly depends on multiple factors including wind speed, direction and obstacles. Midges will travel up to 3km across land. Midges can be transported further in winds across seas.

There is no way of knowing if midges are infected with bluetongue virus. Midges are more likely to be infected with bluetongue if there are reports of the virus on neighbouring farms and within TCZs.

No. There is no evidence that dipping sheep will kill Culicoides or prevent onward transmission of bluetongue.

No. Midges tend to bite around the face, ears, legs etc. which will still be accessible.

Free BTV-3 testing Q&A – June 2024

As the weather gets warmer, the likelihood of BTV-3 incursion is increased, especially in the East and South Coast counties. The testing will reduce the risk of virus spreading to animals susceptible to BTV-3 infection in other areas, via the movement of livestock from the high risk counties.

All ruminants: cattle, sheep, deer and goats, and camelids: alpacas and llamas.

If you are moving lambs and kids that are 3 months or not yet weaned, or calves under a week old, speak to your vet about testing.

Their dam should also be tested before moving – even if you are not moving her. Keep the young with their mother until you have results.

Currently – all livestock keepers in the high risk counties: Norfolk, Essex, Kent, Suffolk and East Sussex.

See if you are in  high risk county here to access the free testing. 

  1. For movement out of the high risk counties, for example animals who are being sold at markets in the high risk counties who may be sold and taken outside of those 5 counties.

  2. For livestock movements out of those counties to live.

You can choose from free sampling and testing, or select free testing only and then pay for sampling from a private vet.

  1. Allow the minimum of 10 working days (Mon – Fri) from applying for testing between application and moving livestock.

The vet should be sampling animals 5 working days before you plan to move livestock.

The results are emailed to you 3 working days after samples are received but allow 5 days for contingency as there may be a delay during busy periods.

If results are delayed, past the planned move or market date, you can move your animals without waiting for the results because testing is voluntary. However, APHA would strongly advise against this. 

No further action is needed – you will not need to complete post moving testing or face additional restriction.

APHA will only share results with you and your private vet if they submitted the samples. You will need to inform the buyer or recipient of the animals of the negative results. 

APHA will contact you and place your premises under restriction while they investigate further. This means you will only be able to move susceptible animals and their germinal products off your premises with a licence. 

APHA official vets will likely re-sample and re-test any positive animals and others in the same group. They will also ask you about the movement history of your animals, including any that have moved off the premises in recent weeks. 

View full information on what may happen next here.  

View the bluetongue disease control framework for 2024 in England 

  1. Please book free testing (and free sampling) by contacting Farmcare: 

– Telephone: 0800 612 5289 (Monday to Friday, 9am to 5pm. You can leave a message out of hours.)

– Email: admin@ukfarmcare.com

The vet will send the samples to APHA or The Pirbright Institute for testing. 

 More info: Bluetongue: get free testing for your animals – GOV.UK (www.gov.uk)

Samples can be submitted only if there is NO suspicion of BTV3 infection.  

Samples should be collected and submitted to Pirbright by the private veterinary surgeon at the client’s expense.  This would be considered good practice when hiring bulls.

Bluetongue FAQs

The following information has been developed with Defra and industry input to ensure farmers and vets have factual, up-to-date information.

Adult animals may show little or no clinical signs, so farmers and their vets need to be vigilant.

In sheep: 

  • Lethargy, reluctance to move 
  • Crusty erosions around the nostrils and on the muzzle 
  • Discharge of mucus and drooling from mouth and nose 
  • Swelling of the muzzle, face and above the hoof 
  • Reddening of the skin above the hoof 
  • Redness of the mouth, eyes, nose 
  • Breathing problems 
  • Erosions on the teats

In cattle:

  • Crusty erosions around the nostrils and muzzle 
  • Redness of the mouth, eyes, nose 
  • Redding of the skin above the hoof 
  • Nasal discharge 
  • Reddening and erosions on the teats 

Cattle do not often show clear signs of disease so owners should also look out for signs of fatigue and lower productivity including reduced milk yield. 

In calves:

Calves can become infected with bluetongue (BTV-8) before birth if the mother is infected while pregnant. Signs of infection include: 

  • Calves born small, weak, deformed or blind 
  • Death of calves within a few days of birth 
  • Abortions 

Livestock keepers and vets should consider bluetongue as a possible cause for calves showing these signs. 

BTV is a notifiable disease which has the potential for rapid spread via biting midges to other ruminating animals with significant production losses in livestock. Suspicion of BTV in animals in England must be reported to the Animal and Plant Health Agency on 03000 200 301. In Wales, contact 0300 303 8268. In Scotland, contact your local Field Services Office. Failure to do so is an offence.

BTV is mainly spread by adult-infected midges (various Culicoides species) biting (vector) an animal susceptible to the disease. This is classed as ‘vector-borne’ transmission.

Infected midges can spread locally and more widely in certain temperatures and wind conditions.

The second but less common way the disease is spread is through movement of infected animals. That is why movement of animals from BTV areas is controlled.

The time of year, i.e. whether during the active vector season (normally March-September), and meteorological conditions, i.e. temperature and wind direction, and the proximity and density of neighbouring farms are significant factors in the potential incursion and spread of this disease. It is however possible to move infected animals at any time of year.

Control of midges is difficult and although there are things that can be done to reduce their spread, it is unlikely that the risk of them can be removed on any individual farm. Reducing the risk is therefore the aim.

The main preventative measure is movement controls and restrictions for susceptible livestock species in relevant areas to reduce the opportunity for vector transmission between holdings. Midges often accompany the animals as they move e.g. in livestock trailers, therefore moving animals increases the risk of midge spread too.

Whilst insecticides do kill insects, their efficacy on Culicoides midges has not been shown outside of the laboratory, and there is no evidence that use of insecticides on animals reduces bluetongue virus transmission in the field.

Whilst treating with insecticides may feel like ‘doing something’, there is no evidence that they will protect livestock from bluetongue and excessive use will cause considerable negative environmental and ecological impacts. Furthermore, these products have a poor retention/efficacy time (especially in the rain) so would require repeat administration.

There are no products licensed for Culicoides ‘control’. Any products sold for this purpose would be off licence and therefore can only be prescribed by vets.

Midges breed in damp soils with high organic content, such as muckheaps. So, keeping these distant from susceptible livestock and livestock-housing may reduce biting frequency and therefore BTV transmission.

Unless specifically directed to by an inspector, or instructed to by the conditions of an official notice, declaration or licence, you are not required to house ruminant animals at your premises. However, you may wish to consult your veterinary surgeon for advice on any protective steps you might take.

Unless specifically directed to by an inspector, or instructed to by the conditions of an official notice, declaration or licence, you are not required to take action to kill or control insects around your premises. However you may wish to consult your veterinary surgeon for advice on any protective steps you might take.

The number for the Bluetongue hotline is 024 7771 0386. NFU members can also access the CallFirst hotline: 0370 845 8458

There are several serotypes of BTV but vaccines are only available for certain serotypes. Unfortunately, there are no authorised vaccines for BTV3 in the UK. Vaccination against BTV3 is therefore not possible.

Vaccines do not offer cross-protection, i.e., vaccinating your animals against BTV8 will not protect them from infection with BTV3.

Unfortunately, there are no authorised vaccines for BTV3. Vaccination against BTV3 is therefore not possible.

The decision to vaccinate against other strains of BTV is a matter for farmers based on the possible impacts for their businesses. In the current situation we do not believe there is a case for mandatory vaccination, nor for the Government to provide or fund vaccination. Our focus is to ensure that farmers and their private vets are fully informed of the current situation.

For serotypes where vaccination is possible (such as BTV 1, 2, 4 and 8), vaccination is the best way to protect livestock. Livestock keepers should discuss with their vet whether vaccination is an option which will benefit their business. Veterinary surgeons can apply to the Veterinary Medicines Directorate for a Special Import Certificate, which will allow keepers to import safe and effective bluetongue vaccine directly from the EU to vaccinate their stock. 

Because BTV is transmitted by midges carrying the virus, and not from one animal to another, vaccination will not necessarily prevent all future potential disease spread but would enable farmers to protect their own herds.   

Unfortunately, there are no authorised vaccines for BTV3 in the UK or EU. Vaccination against BTV 3 is therefore not possible.

  • Following confirmation of BTV in a non-imported animal in England, the UK may no longer be considered as a BTV-free country.
  • Trade with trading partners, including trade to the EU, may be subject to additional control measures imposed by the importing authority.
  • Some countries may restrict UK exports of susceptible animals or their products as a result, although it is expected that exports of many commodities will be able to continue. In some cases, there may be a requirement for additional checks, testing or treatments.
  • The latest information on availability of individual export Health Certificates can be found via Get an export health certificate – GOV.UK (www.gov.uk)

To protect the biosecurity status of Northern Ireland movement of susceptible livestock from GB will now be stopped as epidemiological investigations continue. Movement of germplasm will be subject to appropriate restriction.

Action is being taken to ensure the risk of spread of the disease is reduced – the infected cow has been humanely culled to reduce the risk of onward disease transmission and livestock movements from the affected premises are restricted.

We have also put in place a 10km temporary control zone around the affected farm which will restrict movements of susceptible animals except under license in that wider area, while we undertake additional surveillance to assure ourselves this is an isolated case. The fact that this single case was picked up shows our surveillance programme is working.

Culling may be used in circumstances where it is believed disease is not circulating and an outbreak might be prevented.  Once bluetongue is known to be circulating in the domestic midge population, culling of livestock is not an effective control measure to deal with disease.

If your animal were required to be culled to control Bluetongue disease then you would receive compensation for that animal (unless you had imported diseased animals).  However, we would not expect to cull large numbers of animals since culling becomes ineffective once disease is established within midge populations.

We have robust rules and procedures in place to protect our borders from disease and animals or their germinal products can only be imported if they meet these. It is essential that keepers source responsibly.

Over and above this, we carry out compulsory post-import testing of susceptible animals from areas around and known to have BTV infected regions.

The disease does not affect meat or animal products, and meat and milk from infected animals are safe to eat and drink. Over and above this, we carry out compulsory post-import testing of susceptible animals from areas around and known to have BTV infected regions.

No, BTV viruses do not affect people.

Ruminant wildlife such as deer could become infected if the disease was circulating in the local midge population.

The main direct economic impacts will vary depending on the strain of BTV and at this stage, with only one animal infected, we cannot make such assessments.  

Bluetongue can reduce milk yield, cause sickness, and reduce reproductive performance. The imposition of movement controls may require some farmers to change their usual routes to markets.  Farmers may incur costs from reduced market access, including export markets.

As a notifiable disease, the control of bluetongue is legislated for. The control strategy includes good biosecurity and animal care, responsible sourcing of animals, monitoring of the disease situation in Europe and internationally, and having in place appropriate risk-based import conditions and testing.

Vigilance by animal keepers is key. Anyone keeping an animal must notify any suspicion of notifiable disease. This will be investigated by government veterinary inspectors.

If faced with challenges, there are a number of resources you can access and charities that you can contact for support.

RABI – 0800 188 4444

FCN – 03000 111 999

YANA – 0300 323 0400

Addington Fund – 01926 620135

DPJ Foundation– 0800 587 4262

We Are Farming Minds – 0808 802 0070 / Text – 07786 203 130

Forage Aid – 01926 620135

Mind Charity – 0300 123 3393

Samaritans – 116 123

C.A.L.L (Wales)  0800 132 737

RSABI (Scotland) – 0800 1234 555