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 Bovine TB in GB. Latest SAM data, maps and older VETNET data.
Added or updated 4 days ago
PDF icon Wildlife management and zoonotic infections. A one day symposium held at The Royal Society of Medicine, London on 17 November 2010.
Added or updated 5 days ago
 Gassing of badger setts
Added or updated 6 days ago
PDF icon Badgers prefer cattle pasture but avoid cattle: implications for bovine tuberculosis control. R Woodroffe et al. Ecology Letters. 2016.
Added or updated one week ago
PDF icon Programme for the eradication of bovine Tuberculosis, bovine Brucellosis or sheep and goat Brucellosis (B. melitensis) for obtaining EU cofinancing. Submitted by the Republic of Ireland on 28th May 2015.
Added or updated 3 weeks ago
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Added or updated 4 weeks ago
 Did culling affect TB infection in badgers?
Added or updated 4 weeks ago
PDF icon Post-mortem Examination of TB Reactors (R), Inconclusive Reactors (IRs) and Direct Contacts (DCs): PRELIMINARY RESULTS
Added or updated 4 weeks ago
 An example of how badger culling in the UK is being cast in a negative light
Added or updated one month ago
PDF icon Standard requirements for the submission of programme for eradication, control and monitoring. Submitted 21 Sep 2016 by Rosanne Greene of DAFM of the Irish Republic to the European Commission.
Added or updated one month ago
PDF icon Ireland to be bovine TB free by 2030 under new Government plans - FarmIreland.ie. @farm_ireland. May 10 2018 6:00 AM
Added or updated one month ago
PDF icon Differences between bovine TB indicators in the IAA and the Comparison Area. First six years, 1st May 2010 to 30th April 2016.
Added or updated 2 months ago
PDF icon Results of Badger Vaccination Modelling Report. 3 February 2016. Rebecca Evans, Deputy Minister for Farming and Food.
Added or updated 2 months ago
 Bovine TB in Ireland
Added or updated 2 months ago
PDF icon Badgers removed in the Irish Republic
Added or updated 2 months ago
 Does badger culling make economic sense?
Added or updated 2 months ago
PDF icon Bovine TB Eradication Programme IAA Vaccination Project - Year 4 Report
Added or updated 2 months ago
PDF icon Laboratory Analysis of TB Reactors (R) / Inconclusive Reactors (IRs) and Direct Contacts (DCs) to the Tuberculin Test. APHA. 12/04/2018.
Added or updated 2 months ago
 Data needed to achieve meaningful results in the 2013 badger culls
Added or updated 2 months ago
PDF icon Badger Culling in England By R Giesler et al. House of Commons Library. BRIEFING PAPER Number 6837, 12 April 2018.
Added or updated 2 months ago

Impact of the BCG vaccine on the prevalence of TB in badgers

The largest and most thorough trial of badger vaccination ever undertaken in the UK was conducted in Gloucestershire between 2006 and 2009. The report was peer reviewed and one of the authors was the APHA Chief Scientist Glyn Hewinson.

In the vaccination trial about 200 badgers were vaccinated each year over 4 years over an area of about 55 sq km. Badgers were vaccinated on a group by group basis instead of over one wide area. This means that the mixing between vaccinated and unvaccinated badgers would have been greater in the trial than if the treatment had been implemented in a wide-area roll out. As such the challenge to the vaccine was greater in the trial than in a typical rollout.

What impact did the BCG vaccine have on the prevalence of TB in badgers after 4 years? This is an important question because it is hoped that vaccination will build herd immunity in treated badger populations over the course of time.

The scientists failed to detect a significant herd effect in terms of prevalence in the 200 badgers vaccinated at the end of the 4 years. In fact when these badgers were triple tested in 2009, the prevalence level in the 100 unvaccinated controls was 36.8% and in the 200 vaccinated treated badgers was 33.8%. Another words the prevalence level of TB in badgers had dropped by (36.8 - 33.8) / 36.8% = 8% over the course of 4 years2. When 95% confidence levels are considered this effect is statistically insignificant.

So where is this 79% reduction in risk in unvaccinated cubs coming from?

This is the amount by which TB incidence reduced in unvaccinated cubs. It is thought that TB in these cubs dropped because they were subjected to less infection largely on account of the vaccinated badgers they came into contact with.

Ultimately however what counts is the amount by which TB levels (i.e. prevalence) drops. Incidence is a measure of the number of events which gives rise to TB level. If the incidence drops but does not lead to a drop in TB level, there would have been no benefit.

Although the impact of the treatment on incidence is encouraging, the ultimate test is if TB levels drop. If the treatment is causing badgers to live longer and hence spread their reduced infection during the course of a longer lifetime, it is possible that the treatment had no impact on the overall extent to which they were exposing other badgers (and cattle) to their infection.

To see the report, please refer to,

BCG Vaccination Reduces Risk of Tuberculosis Infection in Vaccinated Badgers and Unvaccinated Badger Cubs

References

  1. Bovine Tuberculosis. Glyn Hewinson. Lead Scientist. APHA. Presentation at EFSA Conference on Wildlife. 5th May 2015, Brussels.
  2. Impact of BCG vaccine on badgers
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