The TVR approach involves capturing live badgers, testing them for TB, vaccinating those that test negative to the disease and removing those that test positive. This balanced approach removes diseased badgers and protects the uninfected ones, which could in time lead to a reduction in transmission of TB from badgers to cattle.
Further information about TVR including related documents are available below.
Further information about the ‘Test and Vaccinate or Remove’ (TVR) wildlife intervention research
How did the idea for a TVR wildlife intervention study come about?
On 3 July 2012, the then Agriculture and Rural Development Minister, Michelle O’Neill MLA, announced to the Northern Ireland Assembly’s Agriculture and Rural Development Committee that, following discussions with industry stakeholders and the views of the external experts, she had asked her officials to design specific wildlife intervention research.
Having considered a range of possible options officials considered that a “test and vaccinate or remove” (TVR) study would increase the evidence base around badgers and bovine TB and help create well-informed and evidence-based strategies to address the issue of cattle-to-cattle spread and badger-to-cattle spread. This approach secured broad spectrum support from stakeholders.
How was the TVR project designed?
The issue of TB and badgers is very complex, emotive and contentious, and any intervention in wildlife incurs substantial cost. Designing a unique study that was both targeted and robust was therefore a complicated undertaking, and a number of steps had to be completed to ensure the approach would be scientifically valid and also provide best value for money.
The first of these steps was to commission mathematical modelling from the Food and Environment Research Agency (FERA) (now the National Wildlife Management Centre) to identify appropriate areas in Northern Ireland of sufficient size for the intervention, as well as the optimum amount of time to carry out the intervention. A copy of FERA’s modelling report is available below.
In early 2013 the Agri-Food and Biosciences Institute (AFBI) was commissioned to commence preliminary badger sett surveys in two 100km2 areas: one between Banbridge and Rathfriland; and one in the Castlewellan / Slieve Croob / Seaforde / Dundrum area. These sett surveys were necessary to gather important information about the number and location of badger setts in the areas before any intervention took place. Permission to access land in these areas was sought from landowners and in most cases was granted.
AFBI staff collated and analysed the data gathered from the sett surveys and this data helped inform the final design and costings for the TVR approach. A final copy of AFBI’s badger sett survey report is available below.
What about perturbation?
The perturbation effect has been observed in England and Wales (for example in the Randomised Badger Cull Trial). The perturbation effect is where a badger population has been disturbed and this disturbance is thought to have caused an increase in cattle TB levels in the surrounding area. However perturbation was not observed during badger interventions in the Republic of Ireland. The evidence suggests perturbation is mostly a factor in areas where the density of badgers is much higher and the social groups are larger.
However any intervention with badgers is closely monitored for effects of perturbation and action is taken to mitigate, as appropriate. This was an important consideration in the study design and is the reason why baseline ecological monitoring was so important.
What criteria were used to select the intervention area?
The modelling work carried out by FERA helped officials identify the optimum duration of the intervention as well as potential study areas that were of sufficient size. This helped ensure the study would be as scientifically robust as possible.
Of the two areas where badger sett surveys were carried out, the Banbridge / Rathfriland area was selected as the TVR study area because it had experienced a higher level of TB breakdowns in the years leading up to the TVR project than the Castlewellan area. Studying the higher incidence area maximised the opportunity to detect a TVR-associated change in incidence levels.
No intervention will take place in the area around Castlewellan, which will serve as one of the “control areas” so that TB prevalence in the study area can be compared against a non-intervention area throughout the life of the project.
What approvals and licences are required for TVR?
A Ministerial Direction was given and Executive approval was granted for the TVR intervention wildlife research in May 2014.
As the badger is a protected species, any direct interventions in the badger population here also require licences from the Northern Ireland Environment Agency (NIEA), which have been granted for each year of the TVR study to date.
How much will the TVR study cost?
The TVR wildlife intervention research was estimated to cost approximately £1-£1.5 million annually. In Year 1 the expenditure for TVR was £1,030,000, and in Year 2 it was £951,000.
What difference is TVR going to make to TB levels in cattle?
The TVR approach has never been trialled in these islands, so it is not possible to know what its impact on the TB levels in cattle will be. That is why DAERA sees value in undertaking this work that is unique and not just an expensive duplication of what is being done elsewhere.
When did the TVR project begin?
The TVR project started in the Banbridge / Rathfriland area on 27 May 2014.
During the first year of TVR all captured badgers were micro chipped, sampled, tested and released after vaccination. This allowed baseline information to be recorded on infection prevalence and various ecological measurements.
From year 2 of the study, infected badgers were humanely euthanised.
How do you know if a badger is infected?
Badgers are captured and blood samples are taken to test for the presence of TB. The badgers detected by the test as TB positive are likely to be those with the most advanced infection, and therefore pose the greatest risk to other badgers and to cattle.
What happens to badgers that test positive for TB?
Badgers that test positive for TB are humanely euthanized by a qualified veterinary surgeon.
What happens to badgers that test negative for TB?
Badgers that test negative for TB are vaccinated to further reduce the disease risk and then released.
What about infected badgers who test negative for TB?
It is possible that a badger with a low level of infection might give a negative reaction to the test. However that badger will be vaccinated before release, which should restrict the progression of the disease. Should its infection develop further we can expect that badger to give a positive response to a subsequent test.
How is the TVR project progressing?
Annual reports are produced for each year of the project and are published on the DAERA website. Links to these and other useful documents are available below.
Once the research is finished will you be rolling out this TVR approach across Northern Ireland?
TVR is a 5-year research project and not a pilot, scheme or trial. This means that certain information obtained during the project, such as badger bTB infection levels and locations, will be kept confidential to reduce premature speculation on project outcomes, especially where derived from interim conclusions or incomplete data. This approach is standard practice for research projects.
It is anticipated that following the completion of TVR field activities in late 2018, a full analysis of data will be undertaken and it is likely that a final concluding report should be available in late 2019. Officials will need to consider the final results from this research when they are available and how these might inform future wildlife interventions in Northern Ireland.
Is this not a case of more research for research sake?
Certainly not. It is vital to ensure we have the evidence base to create well-informed and evidence-based strategies to address the issue of cattle-to-cattle spread and badger-to-cattle spread. This approach has secured broad spectrum support from stakeholders.
Where can I read more about the TVR wildlife intervention research project?
The documents below provide further information about the design and progress of the TVR study.
Reports and publications:
- TVR Wildlife Intervention Research Project - year 5 report (2018)
- TVR Wildlife Intervention Research Project - year 4 report (2017)
- TVR Wildlife Intervention Research Project - year 3 report (2016)
- TVR Wildlife Intervention Research Project - year 2 report (2015)
- TVR Wildlife Intervention Research Project - year 1 report (2014)
- Field Survey for the Presence of Badger Setts in Co Down Northern Ireland
- Questions and Answers about the TVR Badger Sett Survey
- A simulation model to support a study of test and vaccinate or remove (TVR) in Northern Ireland
Press releases and announcements
- Press Release 20 June 2017: Fourth Year of TVR project set to begin
- Press Release 23 June 2016: Third Year of TVR project due to begin
- TVR Press Release 8 July 2015: Second Year of TVR Project Underway (PRONI website)
- Press Release 3 June 2014: Major research project underway to help find a solution to Bovine TB (PRONI website)
- Press Release 7 March 2013: O’Neill announces second badger sett survey in Castlewellan, Slieve Croob, Seaforde and Dundrum area (PRONI website)
- Press Release 29 January 2013: O’Neill announces badger sett survey in Banbridge/Rathfriland area (PRONI website)
- Official Report (Hansard) of Minister O’Neill’s briefing to the ARD Committee on 29 January 2013 including announcement of badger sett survey in Banbridge/Rathfriland area (NI Assembly website)
- Official Report (Hansard) of Minister O’Neill’s briefing to the ARD Committee on 3 July 2012 including announcement about wildlife intervention research (TVR) (NI Assembly website)