Vaccination

The logical way forward is to vaccinate the cattle and this is the one area where both sides agree. The reason we don't vaccinate cattle at this time is we couldn't sell them in Europe due to regulations. This was proposed in 1997 by Lord Krebs in his report. We are waiting for a DIVA test to be accepted to differentiate between vaccinated and wild strains. We are supporting the campaign to vaccinate badgers. Badger BCG can protect a badger from infection. We don't think  that btb is self-sustaining in the badger population. However vaccinating badgers should help protect them from cattle-to-badger infection.

The Badger Vaccine Deployment Project involves trapping and vaccinating badgers (using an intra-muscular injection of BCG) in a 100km2 area near Stroud in Gloucestershire. It dealt with the practicalities of a vaccination programme and in 2011 628 badgers were vaccinated against TB.

The primary aims of vaccinating badgers in the Stroud area are to maintain Fera's capability to vaccinate badgers, and to provide training for others who may wish to apply for a license to do so. The Government are considering vaccination along with culling as components of a package of measures to address the TB issue. 

Laboratory and field studies have demonstrated that vaccination of badgers by injection with BCG significantly reduces the progression, severity and excretion of TB infection.

Chambers et al (2010) showed the BCG vaccination of free-living badgers reduced the incidence of positive serological test results by 73.8%.

 Some wildlife trusts  are currently vaccinating their badgers. This paper was written by Gloucestershire Wildlife Trust.

References

  1. http://www.brockvaccination.co.uk/why-vaccinate-badgers/
  2. http://www.shropshirewildlifetrust.org.uk/Badgers+and+bovine+TB/Badger+vaccination   

 

10:15 Comparing the epidemiological effects of badger vaccination and culling

Prof Rosie Woodroffe, Zoological Society of London

  

Vaccination and culling have both been used in attempts to control wildlife diseases, but work in fundamentally different ways. Culling is intended to reduce transmission by removing infected animals (which can transmit disease) and by removing susceptible animals (which can become infected). By contrast, vaccination is intended to “remove” susceptible animals by making them immune. Although culling is generally intended to reduce disease transmission, badger culling is associated with increases in the proportion of badgers infected with Mycobacterium bovis (the pathogen which causes bovine tuberculosis [TB]). This increase in M. bovis transmission reflects changes in badger behaviour caused by culling. Such changes limit the extent to which culling can reduce the density of infected badgers. Unless badger numbers are drastically reduced, badger culling increases the incidence of TB in cattle.

Fewer data are available on the impacts of badger vaccination for TB control. Nevertheless, scientific consensus indicates that this approach would be expected to reduce the proportion of infected badgers, if implemented annually over several years. Vaccination is likely to be less costly than culling because it is unlikely to require much policing. Costs can be reduced still further by involving volunteers in fieldwork.

There is interest in exploring combinations of badger vaccination and culling. Culling would be expected to undermine the benefits of subsequent vaccination by leaving a lower proportion of susceptible animals to be protected by vaccination. Moreover, evidence suggests that perturbation might also compromise attempts at selective culling of infected badgers.

Overall, badger vaccination may potentially contribute more than culling to eventual TB eradication, because the proportion of infected badgers would be reduced rather than increased. While the consequences of badger vaccination for cattle TB control are still unknown, unfavourable comparisons with culling are frequently based on an incomplete picture of the consequences of culling.

 

 

ROSIE'S POWERPOINT ABOVE AND PRESENTATION BELOW 

 

 

10:35 Badger vaccine development and efficacy

Dr Mark Chambers, Animal Health-­‐Veterinary Laboratories Agency

  

Increased incidence of bovine TB in the UK caused by infection with Mycobacterium bovis is a cause of considerable economic loss to farmers and Government. Eurasian badgers represent the most significant wildlife source of recurrent M. bovis infection to cattle in the UK.

In March 2010 a licence was granted to AHVLA for an injectable form of Bacille Calmette-­‐Guérin (BCG) vaccine for use in Eurasian badgers in the UK -­‐ called BadgerBCG. This was the culmination of 10 years of effort and £11 million of government investment. Vaccination of badgers against TB with BCG is now one of the disease control options available. Over 4000 doses of the vaccine have been administered since July 2010.

To obtain the licence, a series of studies were conducted in both captive and wild badgers to demonstrate vaccine safety and efficacy. I shall describe these and present highlights from the programme of work.

The cost of trapping and vaccinating badgers with BadgerBCG has been estimated to be £1700-­‐£4,000 per km2. A vaccine that can be delivered orally is a potentially cheaper and more practical way of vaccinating large numbers of badgers in the wild than an injectable vaccine, although this is dependent on the required dose and number of baits that need to be delivered per sett to ensure adequate uptake.

AHVLA has been leading on the oral badger vaccine effort since 2005. Whilst the steps to licensing an oral vaccine are the same as for the injectable vaccine the research and development phase is demanding and there is no guarantee of a successful outcome. I shall give a brief outline of some of the issues to consider in the development and licensing of an oral vaccine and describe progress to date. Much of the work is on-­‐going and specific details are commercial in-­‐confidence.

 

https://www.youtube.com/watch?v=0teq0Bt7W4A

 

 

POWERPOINT ABOVE AND PRESENTATION BELOW 

 

 

 

10:55 Development of oral badger vaccines

Dr Eamonn Gormley, School of Veterinary Medicine, University of Dublin

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The eradication of tuberculosis from cattle herds in Ireland and the UK is compromised because infected wildlife species, such as Eurasian badgers (Meles meles), share the same environment and contribute to transmission of infection. The short-­‐term options for dealing with tuberculosis in the wildlife reservoir hosts are limited to segregation of domestic animals from the wildlife or culling of the wildlife host, which remains highly controversial. Vaccination of badgers against M. bovis, if successfully employed, could directly facilitate the advancement of bovine tuberculosis eradication. Programmes of research into vaccination of badgers are being undertaken in both countries and vaccine trials in captive badgers have established that the M. bovis bacille Calmette-­‐Guérin (BCG) vaccine, when delivered by the oral route, can induce a protective response that limits the distribution and severity of tuberculosis disease following experimental challenge. The results from a field oral vaccine trial in Ireland will provide a framework for the development and implementation of strategies that will address the disease in badger populations, and if successful will remove this major impediment to bovine tuberculosis eradication. 

https://www.youtube.com/watch?v=YyUE5oryuUQ

 

 

POWERPOINT ABOVE AND PRESENTATION BELOW

https://www.youtube.com/watch?v=LPtK7-q5T_s

ZSL Badger Vaccination Conference 2013 Dr Eamonn Gormley

 

 

11:30 Badger vaccination – impacts and implementation in the field

Dr Gavin Wilson, Wildlife Programme, Animal Health-­‐Veterinary Laboratories Agency

 

 

BadgerBCG, an injectable vaccine against bovine tuberculosis, was licenced in March 2010 after being shown to be safe and efficacious in badgers. Soon after, the Veterinary Surgery (Vaccination of Badgers against Tuberculosis) Order 2010 came into effect allowing trained lay persons to vaccinate badgers by injection, under the direction of a veterinary surgeon. In June 2010, the Badger Vaccine Deployment Project (BVDP) was launched, aiming to vaccinate badgers in the endemic TB area, build farmer confidence in vaccination, and learn lessons about vaccine deployment. The BVDP area includes over 100 farm premises, covering approximately 100km2 of Gloucestershire farmland. A key component of the BVDP is a bespoke course to train lay vaccinators, approved by the Secretary of State and developed in consultation with the Royal College of Veterinary Surgeons. This four day course covers the essentials of legal responsibilities, cage trapping badgers, and storage and handling of BadgerBCG. Under the Certificate of Competence Scheme, all lay vaccinators submit detailed records to AHVLA showing location and numbers of badgers vaccinated. Hence, we maintain a growing record of all vaccinations carried out in England and Wales. Up to the end of 2012, a total of 4029 vaccine doses had been delivered in England and Wales. In 2012 alone, 998 were vaccinated in the BVDP, 1424 in the Welsh Intensive Action Area, and a further 278 vaccinations were delivered by a range of other organisations. To date, 167 people have attended the training course. Although BadgerBCG has a proven protective effect in badgers, a key knowledge gap is an understanding of the effect that badger vaccination may have on reducing the incidence of disease in cattle. We are discussing with Defra and academic

collaborators the possible use of the growing badger vaccination database to help address this issue.

 https://www.youtube.com/watch?v=     

 

 

GAVIN'S POWERPOINT ABOVE AND PRESENTATION BELOW

https://www.youtube.com/watch?v=                                                                       

 

11:50 From fridge to field -­‐ using badger vaccination at the business scale Dr Gordon McGlone OBE, former CEO of Gloucestershire Wildlife Trust

 

 

BadgerBCG is available as a veterinary product. It can be used by lay badger vaccinators licensed by Natural England working under the aegis of organisations with a Certificate of Competence.

A summary of the practical experience of field deployment of badger vaccination for the period 2011 to 2013 in England has been compiled for a number of SMEs, including not for profit organisations and a specialist commercial company. Estimated and actual costs have been considered and a typical figure for badger vaccination within land management presented.

Conventional audit cycle headings of Commitment, Planning, Doing and Reviewing have been used for compiling a number of recommendations for improvements to and increased uptake of badger vaccination in England at the business scale.

 

GORDON'S POWERPOINT ABOVE AND PRESENTATION BELOW

12:10 Development of cattle vaccines

Dr Martin Vordermeier, Animal Health-­‐Veterinary Laboratories Agency

 

 

Co-­‐authors: Adam Whelan, Bernardo Villarreal-­‐Ramos, Gareth Jones, R. Glyn Hewinson

Cattle vaccination against bovine TB (bTB) is a disease control tool that could reduce the prevalence, incidence and spread of bTB in the cattle population. Bacille Calmette Guérin (BCG), the human TB vaccine, is the only vaccine that could become available in the medium term for use in cattle. However, it is not licensed for this application, and its functional characterization in respect to its protective efficacy and safety in this target species are required to support licensure. As BCG will compromise the specificity of conventional tuberculin based ante-­‐mortem diagnostic tests, there is also a need for the parallel development of associated diagnostic tests that distinguish infected from vaccinated animals (so-­‐called DIVA). Consequently, research in GB has been directed towards these goals, namely the characterization of BCG in respect to efficacy and safety and the development of immunological DIVA. I will summarize data generated towards these two objectives and also highlight issues that need to be resolved before BCG can be trialed in the field, which is one of the conditions sine qua non towards eventual licensure. However, our development efforts are not restricted to testing BCG as we are also developing measures that improve BCG efficacy, such as so-­‐called heterologous-­‐prime boost approaches that comprise of BCG combined with subunit vaccines. We are also exploring the possibility that vaccines can be developed that will not compromise tuberculin specificity, which would allow the continuation with tuberculin-­‐based diagnosis alongside vaccination. An overarching goal is the definition of host biomarkers that predict vaccine efficacy, whose application would significantly accelerate vaccine development. These objectives are not being developed in isolation as we are fully embedded in a wide network of national and international collaborators of researchers working not only on cattle vaccines but also with those engaged in the human TB vaccine development effort.

 

POWERPOINT ABOVE AND PRESENTATION BELOW 

-soon to be uploaded-  

 

 

12:30 The development of a test to differentiate infected from vaccinated animals Dr Cath Rees, Associate Professor of Microbiology, University of Nottingham

 

 

A rapid method for the detection of human tuberculosis was developed by the University of Nottingham in the 1990’s and was commercialised as the FASTPlaqueTB test. We have recently been developing new applications for this bacteriophage-­‐technology, initially focussing on rapid detection of Mycobacterium paratuberculosis (MAP) -­‐ the causative agent of Johne’s disease in cattle. Using the original technology combined with PCR we have

demonstrated the sensitive detection of MAP in blood samples from infected cattle within 48 h. Interestingly we have been able to detect MAP in the blood of cattle in the very early stages of infection, before any signs of clinical disease are evident, and also in animals that give negative antibody-­‐based test results. We have also shown that the same phage-­‐based methodology developed for detection of MAP is able to detect bovine TB. There are many reports in the literature that TB can be isolated from the blood of TB-­‐infected cattle, but this cannot be used as a practical diagnostic method due to the long periods of incubation required, the need to work under high levels of biosecurity, and the low sensitivity of culture-­‐ based methods. We are now beginning to investigate whether the phage-­‐based technology can be used to detect live bovine TB cells in blood samples to form the basis of a DIVA test that can Distinguish between Infected and Vaccinated Animals. To allow high through-­‐put analysis of large numbers of samples we have also developed a new assay format that allows detection and identification of Mycobacterial pathogens within 5 h.

 

https://www.youtube.com/channel/  

 

 POWERPOINT ABOVE AND PRESENTATION BELOW

 

 

 

14:00 Developing policy for the use of TB vaccines in badgers and cattle in England Stephen Cane, Department of Environment, Food and Rural Affairs

 

 

Few people would dispute that achieving freedom from bovine TB in England should be high on any Government’s agenda. There is far less agreement, however, on the means by which it should be achieved – or, more precisely, whether it is right to use some of the available tools at all. So decisions for Ministers on what interventions to deploy – or not deploy -­‐ are always tough and often controversial.

Happily, vaccination is a tool that just about all organisations agree should be in the toolbox. The questions with which Governments grapple then tend to be about how much of a finite resource should be devoted to vaccination – resource for delivery of available vaccines and resource for developing new and better vaccines – which in turn informs things like who does it, what is done and how.

In England, the Coalition Government’s ambition to develop an oral vaccine for badgers and bring a cattle vaccine to the market is evidenced by its investment in R&D. Despite the fact it is possible that research will never yield an efficacious oral badger vaccine, high priority is being given to further efficacy studies. On cattle vaccination, despite the big regulatory hurdles – necessary hurdles given that any veterinary medicine needs to be safe to animals, those who administer them and those who consume their products – work towards field trials likely to cost tens of millions of pounds is moving with pace. It is necessary process, rather than money, that will continue to be the major constraint to progress towards both of these highly prized goals.

There is more of a debate to be had on the ways in which the Government can be the catalyst for increased use of the injectable badger vaccine. There is no sizeable army of public sector vaccinators that could be turned loose in those parts of the countryside where the Government would like to see more and quicker progress. The capacity of others with whom the Government might share responsibility for vaccination is similarly constrained. The uptake of the badger vaccination fund this year is evidence of that. So it is important to look more closely at ways in which capacity can be built and the good intentions of many turned into practical action.

 

 https://www.youtube.com/watch?v=   

 

 POWERPOINT ABOVE AND PRESENTATION BELOW 

 

 

14:30 Developing policy for the use of TB vaccines in badgers and cattle in Wales Prof Christianne Glossop, Chief Veterinary Officer, Welsh Government

 

 

TB eradication is a priority for Welsh Government, farmers and veterinary profession. Launched in 2007, our TB Eradication Programme is based on four basic principles of infectious disease control namely:

⋅ Keeping infection out (biosecurity)

⋅ Rapid early identification of infection Limiting the spread of infection

⋅ Elimination of all sources of infection

Over the past 5 years, the focus has been on the development and delivery of policy at

the national level e.g. annual testing of all herds of cattle, zero tolerance to non-­‐compliance, and increased awareness of biosecurity. It is clear however, that the disease picture across Wales is not uniform, and that alongside these national measures we need also to take a more localised approach. To achieve this we have now appointed a dedicated TB epidemiologist to work with the Animal Health Veterinary Laboratories Agency case vets and also private practitioners to start acting in a more focussed way to deal with the unique characteristics of the TB epidemic of each area. The challenge is to identify the most appropriate tools for the differing disease scenarios – to achieve a more targeted approach as we drive towards eradication.

The overall strategy is underpinned by the recognition that all interested parties need to work honestly and in co-­‐operation with each other – hence our programme structure which includes Regional Eradication Boards and significant engagement at a local level. It also recognises that we must keep abreast of new developments across all disease control disciplines if we are to achieve our ambitious and long-­‐term objective of a TB-­‐Free Wales.

As a long-­‐term objective, we aim to make best use of new technologies as they become available e.g. in the fields of disease prevention, diagnostics and genetics. Vaccination is a tool that has yet to be exploited to the full. This presentation will consider the Welsh approach to exploring the potential benefits and limitations of vaccination in badgers, and in cattle, as we strive towards freedom from TB.

 

 https://www.youtube.com/watch?v=lGMjF-bcPa0

  POWERPOINT ABOVE AND PRESENTATION BELOW 

cal way forward is to vaccinate the cattle and this is the one area where both sides agree. The reason we don't vaccinate cattle at this time is we couldn't sell them in Europe due to regulations. This was proposed in 1997 by Lord Krebs in his report. We are waiting for a DIVA test to be accepted to differentiate between vaccinated and wild strains. We are supporting the campaign to vaccinate badgers. Badger BCG alone is not the solution to bTB, but it does have an immediate effect with no associated negative impact. The Governments Vaccine Deployment Project is one such undertaking. 

The Badger Vaccine Deployment Project involves trapping and vaccinating badgers (using an intra-muscular injection of BCG)in a 100km2 area near Stroud in Gloucestershire. It dealt with the practicalities of a vaccination programme and in 2011 628 badgers were vaccinated against TB.

The primary aims of vaccinating badgers in the Stroud area are to maintain Fera's capability to vaccinate badgers and to provide training for others who may wish to apply for a license to do so. The Government is considering vaccination along with culling as components of a package of measures to address the TB issue. 

Laboratory and field studies have demonstrated that vaccination of badgers by injection with BCG significantly reduces the progression, severity, and excretion of TB infection.

Chambers et al (2010) showed the BCG vaccination of free-living badgers reduced the incidence of positive serological test results by 73.8%.

References

  1. http://www.brockvaccination.co.uk/why-vaccinate-badgers/
  2. http://www.shropshirewildlifetrust.org.uk/Badgers+and+bovine+TB/Badger+vaccination

 

Government Chief Scientific Advisor explains Badger and Cattle vaccination 

Professor Ian Boyd is Chief Scientific Adviser at the Department of Environment, Food and Rural Affairs.

Vaccination will be an important tool to help control bovine TB in the future. But the evidence suggests it will not work on its own – and where both cattle and badgers are concerned, a realistic programme remains a number of years away.

Vaccination and Badgers

Most voices in the debate, including the NFU, support the use of badger vaccination in areas on the edge of the disease spread to help stop bTB spreading further. Farmers are getting involved in badger vaccination projects in these areas because they recognise that vaccination could have a role to play in stopping disease spread.

The Government has also set up the Badger Edge Vaccination Scheme (BEVS) to support badger vaccination projects in areas on the edge of the disease spread that are thought to be most at risk of the disease spreading from the endemic areas of the South West and West Midlands. However, in December 2015 the Government announced that all badger vaccination projects in England were being suspended due to a global shortage of the BCG vaccine. In July 2017 Farming Minister George Eustice announced that the BEVS would restart in summer 2018 and applications for grants from groups interested in running projects would be accepted from late 2017.

The only vaccine currently available for use on badgers is in an injectable form – and that presents problems. You need to cage-trap the badgers to vaccinate them and you have to it annually for a period of 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, every day.

The Welsh Assembly Government is carrying out a five-year badger vaccination programme in the Pembrokeshire hotspot area. In December 2015 the Deputy Minister for Farming and Food, Rebecca Evans, announced that the badger vaccination project in Wales was being suspended due to a global shortage of the BCG vaccine.

In May 2015, the report on the third year of the programme was published and showed that 1,316 badgers had been vaccinated at a total cost of £929,540, or approximately £706 per badger. During the second year of the programme, 1,352 badgers were vaccinated at a total cost of £926,784, or approximately £685 per badger. The first year of the programme saw 1,424 badgers vaccinated at a total cost of around £943,000, or approximately £662 per badger.

There are also question marks over the efficacy of the vaccine. It will not cure a sick badger, one which is already infected with TB. The science suggests the vaccine is most effective in very young animals, and less so in older subjects Read the full report here 

Young badgers spend their early weeks in the sett, making it impossible to trap and vaccinate them and putting them at risk of infection before they emerge. There is also no evidence as yet which shows that vaccinating a proportion of the badger population actually results in a reduced risk to cattle.

An oral bait vaccine is likely to offer the most successful route forwards but this option is still some years away from becoming a part of any badger control plan because there is no licensed or proven oral vaccine currently available. The Government's TB eradication strategy for England suggests 2019 as the earliest when an oral badger TB vaccine may be deployed, subject to research breakthrough and authorisation.

Vaccination and cows

There are calls for cows to be vaccinated against bTB. However, there is no legal vaccine available.

Currently, the only option is the BCG vaccine (Mycobacterium bovis Bacille Calmette-Guérin). The problem is that at present it is impossible to distinguish between a BCG-vaccinated and TB-infected cow, and for this reason, it is currently illegal under EU law to vaccinate cattle with the BCG jab. Work is underway to devise a DIVA test that can Differentiate between Infected and Vaccinated Animals, but even when this has been fully developed, it will need to go through EU and international approval. The upshot is that most estimates say it will be ten years before vaccinating cattle is a realistic possibility.

On top of that, there's evidence to suggest that the BCG vaccine and DIVA test will not eradicate bovine TB on their own. A recent scientific study (see the full report here)  concluded that the efficacy of the BCG vaccine in cattle was between 56% and 68%.

We know the BCG vaccination reduces the progression, severity, and excretion of TB, resulting in reduced transmission between animals, but it is not perfect, and for any vaccine to eradicate a disease it is necessary to ensure that 80% of the target population are immunised. The current BCG vaccine does not shape up.

Scientists have said that vaccination has to be used in combination with other measures, which must include dealing with the disease in badgers. You can read more about bovine TB and cattle vaccination on the Defra website.

Prof Rosie Woodroffe takes an alternative view: 

Prof Woodroffe, who was a key member of the team that spent 10 years and £50m testing badger culling before concluding that culling could "make no meaningful contribution" to reducing bovine tuberculosis (TB) claims Vaccinating badgers would cost less than culling them.

Prof Woodroffe quotes from an analysis of the Governments own data. Woodroffe's analysis used the government's own cost estimates of badger vaccination – £2,250 per square kilometre per year – and the proposed culling – £1,000/sq km/year. When government estimates of policing costs for the cull – £1,429/sq km/year – are added, vaccination becomes the cheaper option.

"Vaccination does not prompt protest, so it is cheaper to implement than culling," said Prof Woodroffe. "There is a good reason to expect badger vaccination to reduce transmission to cattle," She continued "Vaccination is often dismissed as a management option because it has no direct effect on infected badgers. But this is based on a misinterpretation of the available evidence: culling does not prompt a rapid reduction in the numbers of infected badgers."

"The general public does not object to vaccination and there is likely to be no protest whatsoever," said Woodroffe, adding that the Welsh assembly has chosen badger vaccination over culling as its TB control policy and seen no protests. Badger vaccination trials are also being undertaken in England by the Gloucestershire Wildlife Trust and the National Trust in Devon.

Woodroffe said her analysis did not include the additional costs incurred by culling as a result of having to perform expensive surveys to measure badger populations. The cull must kill at least 70% of badgers to ensure escaping animals do not spread TB further but must not kill them all, as local extinctions are illegal. "We know vaccinating badgers reduces transmission of bovine TB to other badgers, so there is good reason to expect it also to reduce transmission to cattle," she said. "Vaccination is also expected to reduce the proportion of infected badgers, rather than increasing it as culling does, so it may have greater long-term prospects for TB eradication." 

The government's cost-benefit analysis predicts a 16% reduction in TB in cattle after nine years as a result of culling but found the cost of the cull exceeded the cost of the TB infections avoided. The scientist who set up the 10-year trials, Lord John Krebs, has described the badger cull as "mindless."

 

 

 

 

 

 

 

 

 

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