As we approach the sixth year of badger culling in Somerset and Gloucestershire, and with more than 40 per cent of the high risk area signed up to manage infected populations, pressure groups are still pushing for a wider roll-out of badger vaccination.
As badger culling continues to be carried out in areas where bovine TB is endemic in England and Wales, wildlife groups and organisations such as the National Trust have ramped up their opposition.
Vaccinating badgers has been held up as a useful tool in the fight against bTB, although some groups see it as a panacea. However, farm leaders, along with some vets and politicians, have urged caution.
The Badger Edge Vaccination Scheme was relaunched by Defra last year following a global BCG vaccine shortage, which halted the programme in 2015.
The programme provides matched funding and training for groups wanting to take part.
The NFU supports the use of badger vaccination in particular areas and circumstances as one tool at the industry’s disposal.
Catherine McLaughlin, NFU chief adviser on animal health and welfare, said it was important to remember vaccination could never be a ‘silver bullet’.
“Vaccination will not work on an animal which already has bovine TB, and no country in the world where wildlife carries the disease has eradicated it in cattle without tackling it in wildlife too,” she said.
“Vaccination can play a part when used appropriately, namely where badgers are known not to be infected. Where badgers are infected, for example in the high risk area, it is not going to be an effective tool. The best tool available to eradicate TB in infected badger populations is a managed cull.”
Sir Charles Godfray, who headed up the review of the Government’s 25-year strategy and published his report in November last year, noted there had never been a large-scale trial of the impact of badger vaccination on disease risk in cattle comparable to the randomised badger culling trial (1998-2005), so the programme’s efficacy was not clear.
Sir Charles added: “Vaccination provides some, but not perfect, protection against infection but does not cure an existing infection and we do not know the duration of immunity.”
Wales was one of the first areas to trial vaccination, along with parts of South West England.
Matthew Thomas, curator of bovinetb.blogspot.com, said the idea badger vaccination was an effective alternative to a cull was a ‘myth’ being pedalled by groups such as the National Trust, Wildlife Trusts and Badger Trust.
“In Great Britain, we have scattered areas culling some 70 per cent of badgers. But many of these have patches, some large, others small, possibly keeping residual infection alive,” said Mr Thomas.
“This has become more apparent with reports from the latest statesponsored vaccinations, along with six-monthly testing and biosecurity, overseen by veterinarians, produced by the Intensive Action Area of Wales [IAA].”
This area reported its six-year results in 2016 and concluded: “Overall, the long-term trends in the IAA and the comparison area are similar.
“Notable differences in indicators of TB incidence have not been seen.”
A year later, in October 2017, University College Dublin and the Quantitive Epidemiology Group in the Netherlands published a joint study on a field trial of badger vaccination.
It concluded ‘a complete lack of effect from BCG vaccination on the infectivity of vaccinated badgers was observed, [for example] vaccine efficacy for infectiousness was 0 per cent’.
A trial led by APHA senior scientist Sandrine Lesellier in 2011 was the only project to carry out post mortem examinations on badgers after vaccination. It found all had lesions and were shedding. One badger was so badly infected it was euthanised.
Dr Lesellier’s team, similarly to previous UK badger vaccination areas, also pre-screened the badgers they used.
After blood and culture tests, they noted: “Each animal was deemed to be TB-free on the basis of three consecutive negative results to both tests spanning 24–25 weeks.”
Mr Thomas added: “This is a different scenario from cage trapping into an infected population, and vaccinating any badger, regardless of its health status.
"The BCG vaccine too is limited in its licensing, having achieved limited marketing authorisation status only in that ‘it does no harm’ to pre-screened badgers’. No efficacy data has been produced to lift this status.”
Last month, Cornwall Wildlife Trust announced its own ‘trailblazing trial’ of badger vaccination in part of Cornwall, ringed by cull areas and the sea.
The trust is seeking donations to help farmers fund it.
Mr Thomas added: “Despite the long-term vaccination results published, the wildlife trusts are encouraging hard-pressed farmers to vaccinate.
“The Somerset cull area struggled, with one farm in its centre vaccinating its badgers. And in south Devon, a National Trust estate, where personal preference and funding overrode established facts also had a trial over several years, with little or no discernible benefit to the tenant’s cattle.”
Last month Defra Secretary Michael Gove said his department would ‘investigate’ a move by the National Trust to prevent its tenants taking part in the badger cull.
The trust believes vaccination, along with improved on-farm biosecurity and ‘changes to husbandry methods’ is enough to get on top bTB.
PROBLEMS WITH BADGER VACCINATION
THE only vaccine available for use on badgers is in injectable form, which presents problems.
Badgers must be cage-trapped to vaccinate them. They must then be vaccinated annually for at least five years.
The process is costly and needs to be carried out by people who have been on accredited courses.
Every trap has to be visited early in the morning each day. A long-standing research programme at the Animal and Plant Health Agency to identify an oral badger vaccine and a palatable bait in which to deliver it is ongoing. Defra said an efficacy study was in progress, with results due later this year.
A debate in Parliament last year heard vaccination was ‘not costeffective’.
However, Labour MP for Derby North, Chris Williamson, who led the debate, argued it was more cost effective than badger culling.
Labour has been vehemently opposed to the badger cull and said it would pull the plug on the scheme if it ever returned to power.