Badgers only need to be vaccinated with BCG once to confer a protective effect on an individual badger. However, it is unnecessary to vaccinate every individual, although the more badgers vaccinated the better overall.
We do not know how long the protection lasts but an annual vaccination campaign is consistent with published results that BCG protection lasts at least one year in animals. Safety data from the Badger Vaccine Study (BVS) on repeated annual vaccinations will be reported in the final report of the BVS which is expected in March 2010.
The temporary marks on vaccinated badgers will last for at least several weeks, depending on weather conditions. This is so a marked badger re-trapped in any given trapping session can be released without further vaccination. There is no need for long-term marking as there is no detrimental effect if a badger is injected again in subsequent years.
DEFRA has recently had a series of meetings with key regional representatives and local veterinary practices in each of the proposed deployment areas. The next step is speaking with farmers in these areas, followed by signing-up participants and training contractors, which will begin during the autumn.
Sign-up will be in phases to allow capacity to be built up and early lessons to be implemented. Therefore, during 2010, vaccination will be carried out in a lead demonstration area, where contractors will be trained, and 20 per cent. (20 km2) of the other five areas. The project will be fully rolled out, in all the areas, by the third year (i.e. all areas will have been vaccinated by 2012). Once this initial phase has been completed vaccination across 100 per cent. of the areas will continue each year and each area will be vaccinated for at least five years.
(2) what estimate has been made of the proportion of farmers and landowners needed to participate in the Badger Vaccine Deployment Programme for the results of the programme to be scientifically meaningful.
The Badger Vaccine Deployment Project aims to increase farmer confidence in TB vaccines and develop practical know-how for vaccinating badgers, including how best to deploy vaccines in an area and developing an understanding of training needs and costs. To this end, we will be monitoring levels of take up among farmers and contractors, and training will be assessed and monitored throughout the project. We will also build up an understanding of the costs of injectable badger vaccination. This information will inform plans for future use of both injectable and oral badger vaccines for bovine TB. Possible further measures of success are currently being considered.
The Badger Vaccine Deployment Project is not a scientific trial, but a practical project to develop know how for vaccinating badgers. The project will target cattle farming areas of up to 100km2 (25,000 acres) in each of the six high incidence TB areas for five years vaccination. While the project will be unable to demonstrate a treatment effect of the vaccine in cattle herds, an exploratory analysis of routinely collected cattle disease data will be carried out at the end of the project and independent expert statistical advice has been taken to ensure the project design gives a good chance of detecting any changes in cattle TB trends that may be associated with vaccination. We expect landowner participation in the project to be at least 70 per cent. within the 300km2 catchment areas, which will enable us to reach our 100km2 target in each area. Social science research looking at changes in farmers’ attitudes to vaccination and factors that influence farmer behaviour can provide meaningful results on a smaller scale. The project design has also been discussed and agreed with the TB Science Advisory Body, along with two of its subgroups dealing specifically with TB vaccines and economics and social science, key farming and veterinary stakeholders and the TB Eradication Group for England.
(2) whether all badgers will be treated as part of the Badger Vaccine Deployment Programme.
All trapped badgers will be vaccinated. It is not necessary to trap and vaccinate every individual in a population or to prevent the entry of unvaccinated ones to control a disease. This is because as the proportion of immunised individuals increases, the risk to all individuals, whether vaccinated or not, decreases. The stable social structure of undisturbed badger populations, where there is little mixing of individuals between social groups, lends itself to the generation of this ‘herd immunity’ through vaccination.
The final business case for the badger vaccine deployment project is still being developed, and cost estimates will be subject to change to reflect, for example, the costs of contractors bidding for the work and the final costs for purchasing the vaccine. We do not propose to release cost estimates until these are more certain.
We do not know at this stage exactly how many people will be employed on the Badger Vaccine Deployment Project. However, we do know that it takes 10 people (five teams of two) to vaccinate a 100 km2 area in one trapping season. The Food and Environment Research Agency (Fera), which already has a number of trained staff, will vaccinate badgers in the training area and will train contractors who will work in the remaining five areas.