1. Badger culling to control bovine TB: its potential role in a science-led policy Professor Christl Donnelly MRC Centre for Outbreak Analysis and Modelling Department of Infectious Disease Epidemiology Imperial College London

2. Percentage of total herds with reactors (confirmed and unconfirmed) 0 0.5 1 1.5 2 2.5 3 3.5 Rest of England and Wales South-West England 1962 to 1996 Gassing 1975 Clean Ring 1982 Interim 1986 Percentage of total herds with reactors (confirmed and unconfirmed)

3. What is the national picture? Released 17 Nov 2010, “according to the arrangements approved by the UK Statistics Authority”. http://www.defra.gov.uk/evidence/statistics/foodfarm/landuselivestock/cattletb/documents/tbpn.pdf 3

4. No culling Reactive culling Proactive culling Randomised Badger Culling Trial (RBCT) areas Randomised to 30 roughly 100km 2 areas where the incidence of confirmed TB breakdowns was greatest No culling outside the field trial areas 4

5. Triplet-specific TB incidence in reactive trial areas observed and predicted had these areas received no culling. Reactives show consistently higher than expected TB incidence in cattle Donnelly et al. Nature 426, 834-837, 2003. 5

6. Policy Advice: Reactive Culling The reactive treatment was associated with a 27% increase in the incidence of cattle TB (p=0.0145; standard 95% CI of 4.8-53% increase) when compared with no culling areas. After adjustment for overdispersion, the CI expands to: 2.4% decrease to 65% increase. “… we conclude that reactive culling of badgers, as carried out in the trial, is unlikely to contribute to the control of cattle TB. … as our results show that reactive culling is unlikely to offer a viable base for future policy, we support the decision to discontinue it as an experimental treatment.” Donnelly et al. Nature 426, 834-837, 2003. 6

7. One hypothesis put forward to explain the reactive culling / increased TB in cattle finding: Culling may disrupt badgers’ territorial organization, so that the remaining animals travel more widely, coming into contact with (and potentially infecting) more cattle herds 7

8. Bait marking is a standard technique for mapping badger home ranges colour marked bait matching bait returns to setts 8

9. To investigate the effect of culling on spatial organization, we carried out bait marking in all three treatments of the RBCT no culling reactive cullingproactive culling 16km 2 study area 24km 2 study area 2004: G, H G, H G, H 2005: B, D B, D B, C, D study areas vary in their culling history with B>C>H>D>G=0 9

10. no culling Triplet D The first comparison: reactive culling Data from the bait marking study were consistent with the hypothesis that badgers range more widely when densities are reduced by reactive culling data from triplets B, D, G & H reactive culling no culling 10

11. Furthermore… Badger densities were slightly reduced, and badger movements expanded, on land immediately outside proactive culling areas badger density badger movement data from triplets B, C, D, G & H This means that, if disruption of badger spatial organization caused the increased cattle TB incidence in reactive culling areas, we should see the same effect on farms neighbouring proactive culling areas 11

12. 0 100km Results from inside proactive culling areas The incidence of cattle TB inside proactive culling areas was 19% lower than that inside no-culling areas (95% CI: 6.2 to 30% lower) Proactive Survey-only Donnelly et al. Nature, 2006. 12

13. 0 100km Results from just outside proactive culling areas The incidence of cattle TB up to 2km outside proactive culling areas was 29% higher than that on farms up to 2km outside no-culling areas (95% CI: 5.0 to 58% higher) Proactive Survey-only Donnelly et al. Nature, 2006. 13

14. Consistency of effects Observed numbers of confirmed breakdowns (following initial culls) and numbers predicted with no culling. Whole trial areas Neighbouring areas Observed Predicted Fewer observed than predicted More observed than predicted 14

15. Effect of repeated widespread culling Trend p=0.17 Trend p=0.064 15

16. The ISG Final Report The Independent Scientific Group on Cattle TB published its final report on the Randomised Badger Culling Trial in June 2007. “After careful consideration of all the RBCT and other data presented in this report, including an economic assessment, we conclude that badger culling cannot meaningfully contribute to the future control of cattle TB in Britain.” 16

17. In Dec 2007, Sir David King met with ISG members “Sir David said he agreed with the ISG’s conclusions regarding the requirements for badger culling to bring about a beneficial effect. He confirmed that badger culling would have to be undertaken competently and sustained for a minimum period of four years over a land area of at least 265km 2. … In response to a question from Dr Woodroffe, Sir David confirmed that conducting badger culls simultaneously over such an area would have to be an essential element of any culling programme that was deemed to have been undertaken competently.” [emphasis added] www.defra.gov.uk/foodfarm/farmanimal/diseases/atoz/tb/isg/mtg131207.htm 17

18. In Dec 2007, Sir David King met with ISG members All present agreed …that sustained, coordinated culling conducted simultaneously over the whole area would be necessary to achieve any improving temporal trend in the effects of culling on cattle TB incidence, and that culling conducted over short time periods or in an uncoordinated manner would be very likely to cause detrimental effects.” [emphasis added] http://www.defra.gov.uk/foodfarm/farmanimal/diseases/atoz/tb/isg/mtg131207.htm 18

19. In Dec 2007, Sir David King met with ISG members Sir David “confirmed that he accepted that badger culling will: cause immigration of badgers into the culled area and the periphery; disturb badger populations in culled areas; disrupt badger social groups in culled areas; cause some badgers to expand their ranging behaviour; reduce spatial clustering of bovine TB infection in badgers; elevate bovine TB infection prevalence in the reduced badger population in culled areas.” http://www.defra.gov.uk/foodfarm/farmanimal/diseases/atoz/tb/isg/mtg131207.htm 19

20. Ongoing monitoring of TB incidence in RBCT areas Jenkins, Woodroffe & Donnelly PLoS ONE Feb (Mar & July) 2010 Defra-funded research 34.1% lower (95% CI: 23.0% to 43.6% lower) 5.6% lower (95% CI: 31.0% lower to 29.1% higher) 20

21. Extrapolating to areas of different sizes Jenkins, Woodroffe & Donnelly Based on PLoS ONE July 2010 Update Defra-funded research 21

22. “The most pressing animal health problem in the UK today is bovine tuberculosis (bTB), which has led to the slaughter of over 250,000 cattle since 1997. As part of a package of measures, we will introduce a carefully- managed and science-led policy of badger control in areas with high and persistent levels of bTB.” 22

23. Bovine Tuberculosis: The Government’s approach to tackling the disease and consultation on a badger control policy “There is no single solution to tackling bovine TB – we need to use every tool in the toolbox.” “The main body of evidence on the impact badger culling has on incidence of bovine TB in cattle is the Randomised Badger Culling Trial (RBCT).” “The results of this trial demonstrate that badger culling, done on a sufficient scale, in a widespread, coordinated and efficient way, and over a sustained period of time, would reduce the incidence of bovine TB in cattle in high incidence areas.” 15 September 2010 23

24. Defra culling proposals “Defra is consulting on a proposal to issue licences to farmers and landowners who wish to cull and/or vaccinate badgers at their own expense. These licences would be subject to strict licence criteria to ensure badger control is done effectively, humanely and with high regard for animal welfare.” http://ww2.defra.gov.uk/news/2010/09/15/control-bovine-tb/ 24

25. Defra culling proposals – Culling method Licences will only permit culling by cage-trapping and shooting, and by shooting free-running badgers, carried out by trained, competent operators with appropriate firearms licences. Defra ruled out gassing and snaring on the basis that we do not have sufficient evidence to demonstrate that they are humane and effective methods of culling. http://ww2.defra.gov.uk/news/2010/09/15/control-bovine-tb/ 25

26. Defra culling proposals - Size This will include a requirement that any culling must take place over a minimum area of 150km 2 so we can be confident it will have a net beneficial effect. This means that we would expect to receive licence applications from groups of farmers and landowners rather than individuals. Applicants will also need to demonstrate that they have considered taking further steps to minimise the potential detrimental effect at the edge of a culling area. http://ww2.defra.gov.uk/news/2010/09/15/control-bovine-tb/ 26

27. Defra culling proposals - Funding The Government will fund the cost of the licensing operation and monitor the effects of the policy. We expect the farming industry to bear the direct costs of badger control. http://ww2.defra.gov.uk/news/2010/09/15/control-bovine-tb/ 27

28. Defra culling proposals – Other proposed licence criteria include The area has high and persistent levels of TB in cattle There is land access for culling for over 70% of the area A commitment to sustaining culling over the area at least annually for a period of at least 4 years http://ww2.defra.gov.uk/news/2010/09/15/control-bovine-tb/ 28

29. Wales – badger culling order The draft Badger (Control Area) (Wales) Order 2010 would allow for a Government-managed cull of badgers, alongside additional cattle measures, in an Intensive Action Area in west Wales. “Under the proposals, there would be an annual cull of badgers over a five year period. Based on the available evidence, at the end of a cull and post cull period (total of 10 years), through culling alone we expect to have reduced bovine TB in cattle in the area by approximately 22%, preventing an estimated 83 confirmed herd breakdowns that would otherwise have occurred in the absence of culling badgers in the area.” http://www.egovmonitor.com/node/38595 29

30. Welsh Assembly Government: Intensive Action Area We currently have the capability and equipment to deliver initially a cull in one area for five years. Expanding above this at this time would have a significant impact on our ability to deliver an effective cull. It is 288km² with a boundary of approximately 97.6km. In defining the boundary of the Intensive Action Area officials have taken the following criteria into consideration: – Level of disease in cattle. – Making best use of geographic and natural boundaries. – Inclusion of whole farms where land is contiguous. – Land usage e.g. cattle, sheep, arable, forestry. http://wales.gov.uk/docs/drah/consultation/100921badgercontroliaaen.pdf 30

31. Although primarily in North Pembrokeshire, it also includes an area of the county of Ceredigion, to the south of the River Teifi, near the village of St Dogmaels, and a small area of the county of Carmarthenshire, to the south of the village of Llanfyrnach. 31

32. Intensive Action Area: Land Access “It is important that we have access to land within the Intensive Action Area so that culling is undertaken efficiently to remove infection, which could result in continual re-infection of cattle. We would hope to gain voluntary cooperation from all landowners in the Intensive Action Area. However, Section 22 of the Animal Health Act 1981 confers power on the authorised officer to enter land to destroy wildlife for the purposes of disease prevention.” 32

33. Respond to your consultation! To respond to Defra (by 8 Dec 2010): TBBC mailbox, Nobel House, 17 Smith Square, London, SW1P 3JR tbbc@defra.gsi.gov.uktbbc@defra.gsi.gov.uk To respond to the Welsh Assembly Government (by 17 Dec 2010): TB Team, Office of the Chief Veterinary Officer, Department of Rural Affairs, Welsh Assembly Government, Cathays Park, CF10 3NQ bovinetbconsultations@wales.gsi.gov.uk bovinetbconsultations@wales.gsi.gov.uk Or use the online form! 33

34. Defra Question 8: Do you agree with the proposed monitoring? Government will take responsibility for monitoring the effectiveness, humaneness and impact of badger control 148. A policy to reduce the reservoir of disease in badgers will need to be monitored in terms of protecting animal welfare, sustainability of the local badger population and observing the effect of the control measures on the disease incidence in cattle. We propose monitoring of the following will take place: – compliance with the licence criteria; – badger welfare – spot-checking carcases to examine whether badgers are being culled in line with the licence criteria; – monitoring the status (numbers) of the badger population to ensure effective control operations and that there will not be local extinction; – incidence of bovine TB in cattle – this will be monitored through active surveillance as at present; and – monitoring protected sites (e.g. Sites of Special Scientific Interest (SSSIs), Special Protection Areas (SPAs)). 34

35. What is the national picture? Released 17 Nov 2010, “according to the arrangements approved by the UK Statistics Authority”. http://www.defra.gov.uk/evidence/statistics/foodfarm/landuselivestock/cattletb/documents/tbpn.pdf 35

36. The picture in Wales The most recent estimates for Wales show that up to the end of February 2010 there were 1,482 herds under movement restrictions, of which, 702 were under restriction because of an overdue test…. Comparative figures for the same period in 2009 were … But for the reduction in overdue tests, these figures would have remained fairly stable. Under TB restrictions Of which, for an overdue test Not due to an overdue test Feb 20081,8011,036765 Feb 20091,8901,050840 Feb 20101,482702780 http://wales.gov.uk/docs/drah/publications/100708tberadreporten.pdf 36

37. The Independent Scientific Group on TB in Cattle 37