As the cull of badgers has recently started in West Somerset and is due to start shortly in Gloucestershire, I feel I cannot let this moment pass without comment. This is obviously a highly controversial and divisive subject but it is also complicated and all aspects of the debate cannot easily be understood via short articles such as this. However, I will try to distil some of the information which I think is particularly pertinent.
First, it is quite clear that the policy of trying to control the spread of TB in cattle is not working. In 1986 only 235 cattle tested positive in Great Britain for TB but by 2010 28,541 cattle tested positive.
It is also important to note that in 1992 the Protection of Badgers Act was introduced which provided legal protection for badgers. As a result the badger population has increased dramatically because the badger has no natural predator. It is estimated that between 1988 and 1997 the badger population increased by 77% and has since increased further to 288,000 in 2005. It is thought the badger population continues to increase and having seen one this summer on the Liberty in Wells and two badgers killed on New Street, I can believe this is true.
It is also not in dispute that Badgers can transmit bovine TB to cattle and despite ever increasing levels of bio-security to reduce the impact of cattle to cattle transmission of TB and a regular programme of cattle testing and slaughter of infected animals, the disease continues to spread in cattle. The implication of this is that cattle herds are in many cases being re-infected from another source, the most likely of which is the badger population.
So what are the options that could be deployed alongside the continuing bio-security measures? I think there are three:
• Vaccination of cattle
• Vaccination of Badgers
• Culling of Badgers
My thoughts on these are as follows:
Vaccination of cattle is currently forbidden under EU legislation. Deploying a vaccine in the face of the European ban could lead to a ban on the trade of live cattle, meat and dairy products with other EU countries. In 2011, these trades amounted to £496,000, £490m and £1.2bn respectively. It is likely that countries outside of the European Union would follow the EU's lead. To change the legislation a significant amount of work will be required proving the safety and effectiveness of a vaccine and developing an effective test to distinguish between infected and vaccinated animals. We are currently many years away from achieving this although if successful, cattle vaccination would become an important element to help control TB in cattle but it would not be a comprehensive solution because the vaccine will not create anywhere near 100% immunity in vaccinated animals.
Vaccination of Badgers is another possibility and trials with an injectable vaccine are underway in Wales for example. However, the cost of doing this on a large scale and the need to vaccinate every year makes this unlikely to be a cost effective or practical solution country wide but it could be used to vaccinate badgers in target areas which could have a role to play in places. If an oral vaccine could be developed this would make it much easier and cheaper to administer a vaccine on a large scale but at present such a vaccine is not available.
Culling badgers is the most controversial proposal. Professor Bourne, who was in charge of the trial badger culls which took place early this century concluded that badger culling did reduce the disease in cattle but also spread the disease at margins of the cull area due to perturbation of badger social groups. As a result he concluded that the badger culling was not cost effective.
Since then Bourne’s conclusions have been open to debate but what has become clear is that continuing to only implement bio-security measures is not cost effective either. There is also a significant body of evidence from abroad that a disease such as TB, where a wildlife reservoir is an important source of re-infection, cannot be successfully brought under control without addressing the problem in the wildlife reservoir also.
Thus it seems to me that culling badgers widely will become an unfortunate but necessary means of bringing this costly disease under control. Culling badgers will only be one aspect of the control measures which will need to be put in place – continued testing and slaughter of cattle, on farm bio-security measures, possible targeted vaccination of badgers and in time the vaccination of cattle are all likely to play a role but there is a long road ahead before the incidence of TB in both cattle and badgers can be brought under control.
First, it is quite clear that the policy of trying to control the spread of TB in cattle is not working. In 1986 only 235 cattle tested positive in Great Britain for TB but by 2010 28,541 cattle tested positive.
It is also important to note that in 1992 the Protection of Badgers Act was introduced which provided legal protection for badgers. As a result the badger population has increased dramatically because the badger has no natural predator. It is estimated that between 1988 and 1997 the badger population increased by 77% and has since increased further to 288,000 in 2005. It is thought the badger population continues to increase and having seen one this summer on the Liberty in Wells and two badgers killed on New Street, I can believe this is true.
It is also not in dispute that Badgers can transmit bovine TB to cattle and despite ever increasing levels of bio-security to reduce the impact of cattle to cattle transmission of TB and a regular programme of cattle testing and slaughter of infected animals, the disease continues to spread in cattle. The implication of this is that cattle herds are in many cases being re-infected from another source, the most likely of which is the badger population.
So what are the options that could be deployed alongside the continuing bio-security measures? I think there are three:
• Vaccination of cattle
• Vaccination of Badgers
• Culling of Badgers
My thoughts on these are as follows:
Vaccination of cattle is currently forbidden under EU legislation. Deploying a vaccine in the face of the European ban could lead to a ban on the trade of live cattle, meat and dairy products with other EU countries. In 2011, these trades amounted to £496,000, £490m and £1.2bn respectively. It is likely that countries outside of the European Union would follow the EU's lead. To change the legislation a significant amount of work will be required proving the safety and effectiveness of a vaccine and developing an effective test to distinguish between infected and vaccinated animals. We are currently many years away from achieving this although if successful, cattle vaccination would become an important element to help control TB in cattle but it would not be a comprehensive solution because the vaccine will not create anywhere near 100% immunity in vaccinated animals.
Vaccination of Badgers is another possibility and trials with an injectable vaccine are underway in Wales for example. However, the cost of doing this on a large scale and the need to vaccinate every year makes this unlikely to be a cost effective or practical solution country wide but it could be used to vaccinate badgers in target areas which could have a role to play in places. If an oral vaccine could be developed this would make it much easier and cheaper to administer a vaccine on a large scale but at present such a vaccine is not available.
Culling badgers is the most controversial proposal. Professor Bourne, who was in charge of the trial badger culls which took place early this century concluded that badger culling did reduce the disease in cattle but also spread the disease at margins of the cull area due to perturbation of badger social groups. As a result he concluded that the badger culling was not cost effective.
Since then Bourne’s conclusions have been open to debate but what has become clear is that continuing to only implement bio-security measures is not cost effective either. There is also a significant body of evidence from abroad that a disease such as TB, where a wildlife reservoir is an important source of re-infection, cannot be successfully brought under control without addressing the problem in the wildlife reservoir also.
Thus it seems to me that culling badgers widely will become an unfortunate but necessary means of bringing this costly disease under control. Culling badgers will only be one aspect of the control measures which will need to be put in place – continued testing and slaughter of cattle, on farm bio-security measures, possible targeted vaccination of badgers and in time the vaccination of cattle are all likely to play a role but there is a long road ahead before the incidence of TB in both cattle and badgers can be brought under control.
James Stephen MRICS FAAV
Partner
Rural Practice Chartered Surveyor, Wells
T: 01749 683381
E: james.stephen@carterjonas.co.uk
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