Mon, 4 November 2019 - 15:33
- Bluetongue virus, in particular BTV8 and BTV4 has been spreading throughout Europe and especially France, Germany, Switzerland and Belgium, which are the nearest countries to the UK under BTV restrictions. We therefore need to develop a surveillance programme to demonstrate to trading partners that we remain free from disease. The survey is designed to detect possible incursions into the UK, which might occur if infected midges are blown across the Channel.
- Bluetongue is a notifiable disease and anyone suspecting disease must report it to APHA. Although cattle can be more frequently infected than sheep, they usually present with mild or no clinical signs. The current BTV epidemic strain can cause milder clinical signs in sheep compared to the 2007 BTV strain but research has shown that the current strain can still severely impact sheep than have not been vaccinated or previously exposed to the virus. Because cattle are more likely to be bitten by midges than sheep, we plan to monitor the disease situation in cattle via targeted laboratory based surveillance in cattle herds.
- A survey has been designed to sample cattle in areas which are considered at greatest risk of incursion due to their relative proximity to the nearest countries to the UK under BTV restrictions. At least 6 farms in each of the counties of East Sussex, West Sussex and Dorset, and 12 farms in Hampshire (including the Isle of Wight), Kent, Essex and Suffolk will be recruited, and sampling will take place in the vector free season, from mid- November 2019 until end of January 2020.
- The Animal and Plant Health Agency (APHA) will be contacting farms registered as keeping cattle in these counties to ask for their participation in the study. Farms scheduled for TB testing during the BTV survey window will be prioritised when possible to reduce inconvenience to farmers. They will run through a short questionnaire (4 questions) which will help to determine which farms are most at risk of bluetongue and therefore most appropriate for inclusion in the study. These questions will also take into account practical consideration such as the availability of handling facilities.
- Veterinary surgeons already commissioned by APHA as part of the Veterinary Delivery Partnership, will visit the farm to collect blood samples from 15 animals and will send them to the National Reference Laboratory at the Pirbright Institute. The blood samples will be tested for bluetongue using PCR and this testing will be paid for by Defra.
- Whilst we expect test results will demonstrate BTV has not arrived in the UK, it is always possible that test results will indicate BTV is present in one or more animals.
- If BTV is detected, the herd will be placed under movement restrictions and an APHA vet will visit to undertake a more thorough veterinary investigation to ascertain how many other animals are affected. To do this, further testing of susceptible animals within the herd will be carried out. APHA may visit other nearby farms to determine whether other animals in the area are affected by Bluetongue virus. They will also try to establish whether there is evidence of BTV circulating in local midges, if present.
- The UK Chief Veterinary Officer will use these findings to decide whether she should declare an outbreak of Bluetongue.
- If disease is confirmed on a premises, susceptible animals will be placed under movement restrictions. We expect infected animals will be restricted for at least 60 days, allowing them to recover from BTV and gain natural immunity. Our disease control strategy will only consider culling animals in very limited circumstances. At this time of year midges, which spread BTV to other animals, are unlikely to be active so it is very unlikely infected animals will need to be culled to stop disease spreading. However, each situation will be assessed on a case by case basis, and in the very unlikely event that an animal is culled market-value compensation will be paid. https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/343402/bluetongue-control-strategy-140727.pdf
- If BTV is confirmed, the survey will cease but disease control measures and surveillance required under the Bluetongue regulations will be put in place.
- We appreciate that the farmers involved in the survey will need to give up their time to facilitate sampling and may have concerns about taking part. Participation in the survey will enable us to meet our legal obligations and to provide assurance to trading partners that the UK remains free from bluetongue. You may recall a similar survey was completed in 2017 and in 2018.
- On the basis of these wider benefits to the industry we seek your support for this project and would be grateful if you could share the information above with your members/clients who keep cattle in these areas so that they are aware of the survey in advance of APHA contacting them.
Defra Exotic Disease Policy Team
APHA Surveillance Intelligence Unit
27 September 2019