Tackling Bovine TB

This blog will provide updates on the work carried out across England to tackle TB in cattle, and share information on the disease and its impact.

Jul 23

Biosecurity Expert Group to help farmers help themselves tackle bovine TB

The first meeting of a bovine TB expert group took place earlier this month. We (Defra) have set up the working group to help prepare a biosecurity action plan which will focus on actions that farmers and others in the livestock industry can take to better reduce the risk of bovine TB infecting and spreading within cattle herds.  The group is made up of representatives from the farming industry – both organisations and individuals, as well as others, including representatives from the veterinary profession, livestock auctioneers, government, and experts on various aspects of bovine TB, including wildlife ecology.  The group aims to finalise the action plan in autumn 2014, after which we will focus on working with industry to take forward the agreed work.

A workshop on biosecurity which ran in May showed that there is a lot of interest in this subject and the first meeting of the biosecurity working group in July built on that.  It was clear from the participants’ energy and expertise that there is a real appetite to work with us to help decide what the priorities should be.  As this is such an important element of our overall strategy for tackling TB, we need to help farmers and others work out what will have the biggest impact in terms of reducing their risk of a TB breakdown and, for those unfortunate enough to have had experience of the disease, how to regain disease freedom quickly and hopefully stay free thereafter.

John Royle, the NFU’s chief farm policy adviser and a member of the working group said: “I’m pleased that Defra has decided to involve an industry group, including farmers from both high risk and low risk areas to work together to develop ideas on how we might target biosecurity and disease prevention measures on farms.   There is so much advice out there, and a lot of it is not relevant or specific to an individual farmer.  Some of the measures are very expensive, not always practical and others require time to install, which farmers may not have.  I hope that this group will come up with a plan which helps us to tackle some of these issues, including access to funding, tailored, expert and independent advice to suit individual needs and circumstances.  Farmers want to know what they can do to reduce the risks to their herds, biosecurity measures are one tool that may help prevent their herd being infected with bovine TB or indeed other diseases.”


Jul 17

Latest bovine TB statistics published

The most recent bovine TB (bTB) statistics are now online. As of the end of April, more than 4,700 herds across Great Britain were affected by bovine TB, and 11,689 cattle have been slaughtered due to the disease.   The charts and tables in this statistical release illustrate how the trend in bTB incidence has changed since 1996. While it’s important to note that short term changes in these statistics should be considered in the context of long term trends, the monthly incidence rate for April is 3.0%. This is the lowest single monthly incidence rate since 2003 and the third consecutive month in which a decrease in the short-term incidence rate has been observed.

Farming Minister, George Eustice said:

“These latest statistics show that our comprehensive bovine TB eradication strategy is beginning to have a positive effect in bringing this devastating disease under control.

“However bovine TB continues to be a major issue for farmers across England. That is why we are using all the tools we have available to tackle the disease, including a new funding scheme to encourage vaccination of badgers in the ‘edge area’ to help prevent bovine TB taking hold there.”

The most recent bovine TB statistics can be viewed here.


Jun 26

Global collaboration at International M. bovis Conference 2014

By the Animal Health and Veterinary Laboratories Agency (AHVLA)

On 16 – 19 June experts in animal disease gathered in Cardiff for a major international conference looking at the global problem of bovine TB.

Co-hosted by AHVLA, the British Cattle Veterinary Association (BCVA), Defra and the Welsh Government, the International Mycobacterium bovis Conference is the sixth in a line of conferences put together under the guiding principle that successful TB eradication is a balance of science, compliance, finance and appropriate control strategies.

Chris, a scientist at AHVLA, was one of the delegates at the conference:

“Every now and again a junior researcher like myself gets the opportunity to attend a big international conference. This year I had the good fortune to attend a key event for TB science, surveillance and policy.

“The first day was a good indication of the varied and enormous scope of what was to come. After opening remarks by Professor Christianne Glossop, Chief Veterinary Officer for Wales, and Professor Glyn Hewinson, AHVLA’s Lead TB Scientist, delegates were treated to a truly international flavour of the importance of bovine TB control around the world.  Keynote talks from staff from the World Organisation for Animal Health (OIE) and the Director General’s office of the World Health Organisation kicked off proceedings, followed by a whirlwind tour of vaccine development from Professor Helen McShane from the University of Oxford. Before long we were whisked off to Australia and New Zealand with topics as varied as risk management and wildlife management.

“Between keynote talks, each day was split into three streams covering topics like vaccination; policy, legislation and regulation; epidemiology and surveillance; diagnosis; practical delivery; social science and economics; wildlife; control; and new methods and innovation.

“Given my work at AHVLA as an immunologist, I attended sessions along the lines of vaccination and diagnostics. However thanks to the world of social media I was able to follow the highlights of talks from other streams using the Twitter hashtag #Mbovis2014. In fact, Doctor Gareth Enticott from the University of Cardiff has collated all the tweets here.

“With such busy days there was too much to describe here so I’ll give you some of my personal highlights. Tuesday began with a fascinating keynote talk from Professor Ian Boyd, Defra’s Chief Scientific Advisor, about the use of evidence in policy making, and another from Peter Roeder about the practicalities of disease eradication.

“Wednesday gave us DIVA (Differentiate Infected from Vaccinated Animals) skin tests and comparisons of diagnostic tests in Mozambique.

“On Thursday we discussed the Slovenian TB eradication programme; the role of shooting permits in controlling white-tailed deer in Michigan; whole genome sequencing in New Zealand and the history of M. bovis and M. tuberculosis in Nigeria.

“It fell to Michael Sheridan, the deputy Chief Veterinary Officer for Ireland to provide the closing remarks and bring to an end the sixth International M. bovis Conference.”


Jun 11

New measures announced to help tackle bovine TB

Further measures to strengthen our bovine TB cattle controls and prevent the spread of disease have been proposed in a consultation which began today.

The proposals come as new statistics published today show that the tough measures taken to combat bovine TB are starting to have an impact, with the rate of new herd infections at its lowest point for 10 years.

Farming Minister, George Eustice said:

“Today’s statistics show that the controls in our bovine TB eradication strategy are beginning to make a difference and the further measures announced today will help even more to bring this devastating disease under control.

“However we cannot become complacent. The impact of bovine TB on our cattle farmers, their families and their communities cannot be overstated. That is why must do everything we can to reach our aim of making the whole of England TB free.”

The consultation proposes the removal of pre-movement exemptions for cattle moving between several holdings under the same farm ownership, known as Sole Occupancy Authorities. This will remove the possibility of some cattle keepers in the high risk and edge areas moving their animals over long distances without any TB testing.

Since 1 January 2014 owners of herds who fail to complete their TB surveillance test on time risk seeing their CAP scheme payment reduced, even if the test is delayed by only one day. The consultation also sets out our intention to extend this approach to also include TB tests in restricted herds.

Our current approach has already helped achieve a 60% reduction in late TB surveillance tests this year. As is the case now, farmers will not be penalised where there are good reasons for missing a TB testing deadline.

The latest bovine TB statistics show that the monthly incidence rate, which is the proportion of new outbreaks discovered through testing, was around 3.25%. This is the lowest rate since 2004 and follows a similarly low rate in February of 3.5%.

For more information visit https://www.gov.uk/government/news/new-measures-announced-to-help-tackle-bovine-tb


May 14

Latest Bovine TB statistics published

The most recent bovine TB (bTB) statistics are now online. These show that bTB continues to be a major issue for farmers across England and they reiterate the need for further robust action to tackle the disease in areas where it is endemic and prevent it from spreading further to the “edge areas”.

Since the beginning of this year another 5,928 cattle in Britain have been slaughtered due to the disease.

Other statistics published this month show that the number of new herd incidents during the two months to 28 February 2014 was 955 whereas the corresponding figure in 2013 was 898.

The charts and tables in this statistical release illustrate how the trend in bTB incidence has changed since 1996. It’s important to note that short term changes in these statistics should be considered in the context of long term trends.

The full statistical release can be found here:

https://www.gov.uk/government/publications/incidence-of-tuberculosis-tb-in-cattle-in-great-britain


May 12

David Barton, a Gloucestershire beef farmer, has been battling bovine TB on his farm for years. 

Last week he invited the NFU on to his farm to film four of his cattle, including his stock bull Ernie, being shot and removed after they had tested positive for bovine TB.

Writing on a blog he has created to share his experiences of dealing with bovine TB, David said Ernie had been the last animal to be tested and he never thought he would test positive for the disease.


Apr 16

Environment Secretary visits farm devastated by bovine TB

Environment Secretary, Owen Paterson visited a dairy farm in Dorset yesterday and met with a farmer who lost 31 TB infected in-calf heifers on Monday and a further five cows yesterday.

image

You can learn more about this farm on ITV News West Country here.


Bovine TB statistics and your chance to feed-back

The most recent bovine TB (bTB) statistics are now online. These show that bTB continues to be a major issue for farmers across England and they reiterate the need for robust action to tackle the disease in areas where it is endemic and prevent it from spreading further to the “edge areas”.

Since the beginning of this year 2,924 cattle in Britain have already been slaughtered due to the disease.

The charts and tables in this stats notice illustrate how the trend in bTB incidence has changed since 1996. It’s important to note that short term changes in these statistics should be considered in the context of long term trends. For example, the provisional incidence rate for January 2014 is 4.3% which is the same as in January 2013, but higher than the incidence rate of 1.5% in January 1996. The recent figures include a number of unclassified incidents, and as such the incidence rates are subject to further revisions as more tests and their results for the period are included.

Other statistics published this month are the number of new herd incidents up to January 2014. These were 534 in January 2014 compared with 498 for January 2013. And the number of tests on officially TB free herds was 8,083 during January 2014, compared with 7,347 during January 2013.

The TB statistics team is seeking feedback on the statistical notice over the next six weeks. There is a link to the survey next to the full bovine TB statistical notice, which can be found here: https://www.gov.uk/government/publications/incidence-of-tuberculosis-tb-in-cattle-in-great-britain


Apr 3

Independent Expert Panel report and Defra response

The findings and recommendations of the Independent Expert Panel on the pilot badger culls in Somerset and Gloucestershire:

https://www.gov.uk/government/publications/pilot-badger-culls-in-somerset-and-gloucestershire-report-by-the-independent-expert-panel

Defra’s response to the report by the Independent Expert Panel on the pilot badger culls in Somerset and Gloucestershire:

https://www.gov.uk/government/publications/pilot-badger-culls-in-somerset-and-gloucestershire-defra-response-to-the-report-by-the-independent-expert-panel


Plans to eradicate bovine TB in England unveiled

A comprehensive Strategy to achieve TB free status in England by 2038 has been announced by Environment Secretary Owen Paterson today.

Read the strategy here.

This includes continuing to strengthen cattle movement controls, a grant-funded scheme for badger vaccination projects in the ‘edge area’ at the frontier of the disease, and improvements to the four-year badger cull pilots in Somerset and Gloucestershire.

image

Following recommendations from the Independent Expert Panel that assessed the badger cull pilots last year, a series of changes will be made to improve the effectiveness, humaneness and safety of culling. These changes will be monitored to assess their impact before further decisions are taken on more badger cull licences next year.

Environment Secretary Owen Paterson:

The four year culls in Somerset and Gloucestershire are pilots and we always expected to learn lessons from them.

It is crucial we get this right. That is why we are taking a responsible approach, accepting recommendations from experts to make the pilots better.

Doing nothing is not an option. Bovine TB is a terrible disease which is devastating our cattle and dairy industries and causing misery for many people in rural communities. We need to do everything we can, as set out in our Strategy, to make England TB free.

Improvements to the pilot culls will include more extensive training for contractors carrying out the cull, better planning by the licensed companies to ensure culling is spread evenly across all land available and better data collection to assess progress. The changes being introduced will help increase the effectiveness of the culls by removing more badgers in a safe and humane way.

There will be a trial of a new service in Somerset and Gloucestershire to provide farmers with bespoke advice on how to better protect their farms from disease. This service will be available to all farmers within the licensed cull areas.

Addressing bovine TB in badgers in high risk areas is just one part of a new long-term strategy to eradicate bovine TB from England. The strategy demonstrates the wide range of tools we will use to achieve TB free status by 2038. This includes:

Offering grant funding for private badger vaccination projects in the edge areas aiming to increase TB immunity in uninfected badgers and reduce the spread of the disease. Defra will provide match-funding for successful applicants;

  • Continuing to strengthen our cattle movement controls and testing regime to stop the disease from spreading from herd to herd;
  • Improving biosecurity by helping farmers understand the disease risk of cattle they buy; and
  • Continuing to invest in development of a new vaccine for cattle which could be field tested next year, and an oral badger vaccine which we would look to have available for use by 2019.

The scale of the problem is different across the country, so we will establish three bTB management regions known as the High Risk Area, Low Risk Area and the Edge area. A range of measures will be applied to control the disease within each zone according to the risk.



Video explaining what bovine TB is, and what the Government is doing to tackle it. 


Mar 27

Cases of TB in domestic cats and cat to human transmission

Two people in England have developed TB after contact with a domestic cat infected with Mycobacterium bovis (M.bovis). M.bovis is the bacterium that causes TB in species such as cattle.

Public Health England and the Animal Health and Veterinary Laboratories Agency have made an announcement today, the full press release is here: http://www.defra.gov.uk/ahvla-en/files/20140327-cat-tb-news-release.pdf


Mar 12

90 cattle killed each day due to bovine TB

32,620 cattle were slaughtered in Great Britain due to bovine TB (bTB) in 2013, new figures released today reveal.

This equates to almost 90 cattle being killed each day as a result of the disease.

The figures published today also show that the incidence rate – i.e. the proportion of previously TB-free cattle herds found to be infected with new incidences of the disease – was 4.5%. This means the rate has been at an unacceptably high level of above 4% for a decade and shows the steady toll of bovine TB on British cattle herds.

Farming Minister George Eustice said:

“Our efforts to control bovine TB have kept outbreaks steady over the last ten years, but we are still nowhere near an acceptable position. Almost 90 cattle are being slaughtered each day due to bovine TB and we cannot allow that to continue.

“Today’s figures are another reminder that we need to do all in our power to bear down on a disease that is costing taxpayers millions each year and taking a terrible economic and emotional toll on our farmers.”

Defra consulted on a 25-year TB eradication strategy last summer, which included proposals for disease surveillance, pre- and post-movement cattle testing, removal of cattle exposed to bTB and wildlife controls including culling and vaccination trials.

The final strategy will be published this Spring. It will also focus on the development of new techniques such as badger and cattle vaccines and new diagnostic tests that could one day offer new ways of tackling the disease.

The latest figures can be found here.


Mar 10

Bovine TB Q&A - March 2014

Many of our Twitter followers have submitted questions to us on bovine TB and our strategy to combat the disease.

We’ve compiled answers to these questions in the blog post below.

- Previous attempts to determine the badger population show a wide margin of error, within the pilot culls zones the numbers were shown to have decreased dramatically; why do we need to control the population of an animal which is obviously not ‘out of control’?

Previous studies have shown a clear epidemiological link between the presence of TB in badgers and the occurrence of TB in cattle and a positive effect of culling of badgers in reducing the incidence of TB in cattle herds. It has been estimated that in high incidence areas up to 50% of cattle herd breakdowns are directly or indirectly caused by badgers. Therefore it makes sense for control of badger populations to be part of the strategy in controlling TB in cattle in areas with a persistently high incidence of TB, such as the South-West and West of England.

- If contraceptives are used, will you be conducting a thorough population and density count to determine which areas they should be deployed?

Contraception of badgers is still at the early stages of development and is not yet ready for use within the TB control programme. It may be some time before this is ready and, if considered an appropriate tool for controlling TB, the strategies for using this in the field will be considered later on.

- If it has to be injected into the animals or needs to be ingested in bait, why do you not just vaccinate them using the same methods?

Currently the leading badger contraceptive being tested is in an injectable format. In theory, it could be used alongside injectable BCG vaccination. However, as stated above, methods of administration will be considered at a later date if contraception is used within the TB control strategy.

- How will this be targeted and how will you ensure that it does not cause whole clan infertility leading to local population extinctions?

Contraception of badgers is still at the early stages of development and therefore is not yet ready for deployment within the TB control programme. If used, it would form part of a control programme to manage, but not eradicate wildlife populations. “Whole clan infertility and population extinction” through contraception alone would require treatment of all animals in the population and for the contraception method to have 100% efficacy; however, this has not been demonstrated in other species where immunocontraception has been used.

- If the contraceptive is not targeted and needs to be ingested in bait, what are the effects if only male badgers eat the drug? Does it have any contraindications to the male biology?

As above, we have not yet considered if immunocontraception will be used in the TB control programme and, if used, have not yet considered the method of administration. The effect on males is an aspect that would need to be examined.

- Badgers cubs have a high mortality rate with less than 50% reaching the age of one year and badgers as a species are slow to reproduce and grow, therefore, why is control even necessary?

A recent survey of badger setts in England and Wales has been published and the findings indicate that badger populations are growing. By comparison with data recorded 25 years previously, the annual rate of increase in the estimated number of badger social groups was 2.6%, equating to an 88% increase across England and Wales. In England, the study estimated an increase of 103% in badger social groups, while in Wales there had been little change.

- What is the minimum viable population number for badgers?

There is no agreed minimum viable population density for badgers. Although densities in the South-West and West of England are amongst the highest in Europe, badger populations can be viable at lower population densities.

- The recent floods and extreme weather will have had a major impact on badger populations, why are you looking to control a population which may already be weakened?

There is currently no evidence that the national badger population has been significantly affected by recent flooding.

- M.bovis can survive outside of a host in environmental reservoirs such as slurry and within protozoa, will flooding cause the disease to spread to new areas?

Water-borne transmission is not considered a significant route of transmission of bovine TB. The main route of transmission is through aerosols.  While M.bovis can survive in the soil for a period of time under the right circumstances, the bacterium cannot replicate in the soil and transmission direct from soil has not been shown to be a significant route of transmission. Nevertheless, routine surveillance for TB will continue in cattle herds, which will indicate if TB levels have changed as a result of flooding.

- What is being done to control any disease spread from environmental reservoirs caused by the recent floods?

The winter floods have not had a major impact on the TB testing programme for cattle.  In cases where tests have been delayed (including as a result of flooded cattle farms), herds will stay under movement restrictions until the required TB test is completed.  All the cattle in annual TB testing areas that need to be relocated because of flooding are subject to statutory pre-movement TB testing.  Where it is not possible to carry out the necessary test prior to the cattle being moved out of the affected farm, AHVLA will issue a movement licence for the farmer and the animals will be post-movement tested while in isolation on the destination farm.

- As Bovine TB has now been detected in the New Forest, do you plan to test all ‘commoner’ cattle for the disease?

Farmers with grazing rights on common land already undergo regular surveillance testing, including in the New Forest. All cattle herds in Hampshire are now tested annually since the rollout of a new cattle TB surveillance strategy for England in January 2013.

- In ideal conditions M.bovis can remain viable within the soil for more than 15 months; do you therefore accept that testing setts is not a workable method to determine badger infection?

None of the potential approaches for testing badger setts for evidence of M.bovis infection is based on soil testing, therefore the presence or absence of surviving M.bovis in the soil does not affect options for sett based diagnostics.

- Although you have suggested biosecurity measures to control the disease, these have mainly been attributed to either cattle or wildlife hosts, what biosecurity measures do you have planned to tackle environmental reservoirs of the disease?

A wide range of biosecurity proposals and measures can be found in our draft strategy to achieve bTB-freedom for England. This includes measures to minimise direct and indirect (environmental) contact between cattle and badgers. In order for biosecurity measures to be effective, they should focus on the principle hosts of infection which are cattle and badgers. In relation to environmental sources, while M.bovis bacteria can survive in the soil for a period of time under the right circumstances it cannot replicate in the soil and transmission direct from soil has not been shown to be a significant route of transmission. 

- Are cattle vaccination trials being delayed?

No. We have not postponed trials for cattle vaccination. Defra are progressing with work on a viable cattle vaccine, according to the provisional timeline set down by the European Commissioner for Health and Consumer Safety in January 2013 and the scientific opinion issued by the European Food Safety Authority in December 2013. We are currently on target to deliver a workable vaccine for domestic and international use by 2023.

- How can infected cattle be taken away to be processed abroad, but vaccinated animal products cannot be exported?

The Food Standards Agency ensures that all TB reactor carcasses are fit for human consumption through ante and post-mortem meat inspections. The vaccination of cattle against TB is currently illegal under EU animal health legislation.

- Cattle have been moved from the flooded areas in Somerset without pre-movement testing being performed. Now that these animals are safe, will any further movement be restricted until further tests can be administered?

Cattle that must be moved because of flooding are required to be post-movement TB tested following isolation on the new holding, unless they recently underwent testing for the disease.  This is normal practice in circumstances where pre-movement testing of cattle is unsafe for any reason or when the welfare of the animals dictates that the move needs to happen immediately.

- If other farms have taken in cattle which have been affected by flooding, will those farms now be placed under movement restrictions?

Herds moved on new holdings as a result of flooding are kept in isolation while waiting for post-movement testing, unless recently tested.

- Due to the floods, cattle are being kept inside sheds and barns for extended periods. Being in such close contact for a prolonged period of time may increase bovine TB incidence within herds, how has dealing with this been planned for?

Farmers are expected to take the standard biosecurity and husbandry precautions on their holdings to minimise the risk of TB spread. It is not unusual for cattle to be kept indoors during winter.

- Even in areas which have not flooded, rain fall has been at an all-time high. Liver fluke have increased in number and range due to these warmer, wetter conditions; studies have shown that infection with the parasites alters a cow’s reaction to the skin test, how will you prevent hidden Bovine TB cases caused by the fluke?

The TB testing regime in England is based on the best diagnostic tests available, and research shows that cattle which have both liver fluke and bovine TB can still be detected by the existing TB tests. Furthermore, the programme of cattle TB testing on farms is supplemented by TB surveillance at routine slaughter of cattle by post-mortem meat inspection.

- Open-shooting is not a sustainable form of controlling a badger population, as the costs now outweigh even a government roll out of vaccination, has vaccination become a more viable option?

We will be publishing an updated analysis of the costs and benefits of badger culling when we make a decision on whether to roll-out culling more widely.

- On which projects/ initiatives has DEFRA spent money in the past three years with a projected Benefit to Cost ratio worse than 0.8 (that estimated for the badger culls)?

The first year into a four year cull is too early to speculate over its impact. The benefits of badger culling, measured in terms of reduced cattle TB, are expected to be delivered over a 10 year period.

- The NFU had a presence within the pilot culls, how much of the policy costs did they absorb if any?

The farming industry is responsible for the operational costs of delivering culling.

- If culls are rolled out, will any culled badgers be tested for Bovine TB this time? The vaccination programme in Wales has stated that no badgers caught have shown any visible signs of infection (and would therefore not be infectious/be shedding any bacteria), so it is important to know the current disease levels in the badger population to determine whether this policy will have any disease control benefits.

There is no compelling case for testing badgers for TB. We already have evidence from the Randomised Badger Culling Trials on the role of badgers in the spread of the disease in endemic areas and how TB in badgers changes with culling.

- Why is not more education given regarding anergic animals within a herd? And when will Gamma Interferon testing be introduced for herds with repeat breakdowns?

TB infected cattle are usually identified, through the routine herd surveillance testing programme, before they become anergic with advanced disease. Nevertheless, our draft strategy to achieve bTB-freedom for England recognises the limitations of the skin test in terms of its sensitivity.

The roll out of interferon (IFN) gamma testing is prioritised with the initial aim of preventing new hotspots of TB becoming established in the low risk areas and the edge of the high risk area, rather than in high risk areas with long-term breakdowns.  Nevertheless, the IFN-gamma test continues to be available on a case-by-case basis as a tool to control persistent TB breakdowns. The AHVLA announced at the beginning of February the adoption of a new procedure for the enhanced management of chronic TB breakdowns in cattle herds, which includes the IFN-gamma test. 


Page 1 of 8