Do badgers actually have TB and could they infect cattle even if they do?

[DrS]

There's a fuss in Wales at the moment over a proposed badger cull which has been stopped by the appeal Court. The judgement in favour of the anti-cull movement's appeal was on a technicality of area, so it seems to me, but the issue has brought up all the usual "well it wouldn't be effective anyway" arguments. Some go even further and say it's not an issue of effectiveness at all, but of bad science, and that badgers are not infected with TB anyway.

I've always tended to side with the anti-cull lot because, let's face it, badgers are just totally sweet, and the idea of killing them en masse when it's not even certain that they're infected let alone capable of infecting cows if they were. The fact is, though, that I actually have no idea which side is right in this debate, if either! Does anyone know?! Is there any clear statement that can actually be made?

THIS is the BBC report into the latest row.

[Harryprice]

The obvious long term solution has always been a TB vaccine for badgers like the one that worked so well for rabies in foxes on the continent. Hopefully, it will not take long now if this is anything to go on. The obvious objection to a cull is that a major study of such a cull showed it would not be effective.

[panama]

The farming lobby have been pushing for this for some time and there does appear to be a link between wild badger populations and the incidence of Bovine TB. I'm unaware of the reason for not choosing the simplest option, i.e. inocculating the cattle.

[Harryprice]

The farming lobby have been pushing for this for some time and there does appear to be a link between wild badger populations and the incidence of Bovine TB. I'm unaware of the reason for not choosing the simplest option, i.e. inocculating the cattle.

If they innoculate cows, most countries will allow them to be imported. I think the problem is to do with telling the difference between whether a cow has been innoculated or actually exposed to TB.

[Drop Bear]

Don't know. We don't have badgers here.

However,on a recent Doc Martin, a badger infected a dog with TB*. The dog then infected a child.

Although I can't use that as evidence, I think it may be an indicator of a common perception in the UK.


*Or was it rabies? We don't have rabies in Australia.

[Pebble]

Some go even further and say it's not an issue of effectiveness at all, but of bad science, and that badgers are not infected with TB anyway.

.

Well this bit is incorrect any way.

http://www.ncbi.nlm.nih.gov/pmc/arti...1/?tool=pubmed

Data and samples were collected from wild badgers living in the Woodchester Park study area, a 7 km2 region of Cotswold limestone escarpment in Gloucestershire, south-west England (51°43′N, 2°16′W). The resident population of badgers (approximately 300 individuals in 26 social groups) has been the subject of long-term research into badger ecology and TB epidemiology, details of which are given elsewhere

The cross-classified results of the three diagnostic tests are presented in Table 2. Fourteen of 875 samples (1.6%) cultured positive for M. bovis, whereas 177 (20.2%) tested positive using IFNγ, and 114 (13.0%) gave a positive Stat-Pak result.


The difficulty arises in determining just how common TB is. Culture is very accurate, but culture is often negative in infected individuals. Based on post mortem series, studies of the performance of tests in deliberately infected animals and some modelling the estimated actual prevalence in this particular population of badgers is around 20%.

[Tony Williams]

As I understand it, badgers can probably infect cows but, equally, cows can infect badgers...

[smudge]

The evidence here is patchy and inconclusive.
Even if it were proved that badgers spread TB among cattle there is a moral question to be tackled. Is culling one animal to reduce risk of disease in another animal justified? Is the fact that one of these animals is profitable to some humans relevant? On what basis do we make such judgements?

The farming lobby is a strong one. In my view this is why the cull had been pushed through on the back of inconclusive data and without the moral issues debated thoroughly.

You could argue for a cull in cattle. They may be spreading disease in the badger population.

[DrS]

The difficulty arises in determining just how common TB is. Culture is very accurate, but culture is often negative in infected individuals. Based on post mortem series, studies of the performance of tests in deliberately infected animals and some modelling the estimated actual prevalence in this particular population of badgers is around 20%.

Thanks Pebble. At least it's demonstrated that there is TB, even if in possibly low numbers. So the questions are can they spread it, and if so, to what extent and what would that effect be on the bovine population. Seems to me the question of what to do about it depends on the answer to those questions.

The evidence here is patchy and inconclusive.
Even if it were proved that badgers spread TB among cattle there is a moral question to be tackled. Is culling one animal to reduce risk of disease in another animal justified? Is the fact that one of these animals is profitable to some humans relevant? On what basis do we make such judgements?

Agreed.

[blackjack]

You could argue for a cull in cattle. They may be spreading disease in the badger population.

Cattle who react to the TB test are already being culled.

Re. vaccination - is there a vaccine for cattle? Is there one for badgers?

It does seem odd to me that badgers are next for the chop. As it has always seemed odd to me that cattle are the only species to be culled at present. Surely the only way to eradiate a disease (aside from mass vaccinations) is to remove ALL diseased animals. Deer can get bovine TB too and I would imagine that other species can also. I don't see how wild animals can be tested for the disease, at least not with the current test.

[Harryprice]

It does seem odd to me that badgers are next for the chop. As it has always seemed odd to me that cattle are the only species to be culled at present. Surely the only way to eradiate a disease (aside from mass vaccinations) is to remove ALL diseased animals. Deer can get bovine TB too and I would imagine that other species can also. I don't see how wild animals can be tested for the disease, at least not with the current test.

As iI said upthread, the obvious solution is to vaccinate wild populations of badgers (which should be happening soon). This worked on the continent to get rid of rabies in wild fox populations. Continuing to cull cows with TB assists this process, helping to eliminate reservoirs of TB.

[smudge]

Cattle who react to the TB test are already being culled.

You miss the point. Under the proposed cull, badgers were to be trapped in cages and shot. Not tested. Just shot. Despite evidence suggesting such a policy is ineffective.

[panama]

It does seem odd to me that badgers are next for the chop. As it has always seemed odd to me that cattle are the only species to be culled at present. Surely the only way to eradiate a disease (aside from mass vaccinations) is to remove ALL diseased animals. Deer can get bovine TB too and I would imagine that other species can also. I don't see how wild animals can be tested for the disease, at least not with the current test.

That might be a little difficult. Can you imagine the logistics of catching and testing every wild animal in the country?

[smudge]

Plans to cull in England; http://www.guardian.co.uk/environmen...land-jim-paice

The most recent major study, published in February, found that badger culling is unlikely to halt the spread of bovine TB. The research examined the disease in regions where culls had been trialled. While widespread and repeated badger culls reduced the numbers of infected cattle, the disease returned to its original level four years after the programme ended, scientists found. Managing badger populations to stop them spreading TB to cattle also cost more than the impact of the disease, researchers from Imperial College and the Zoological Society of London said.

[Harryprice]

I had given this new government the benefit of the doubt until now but the decision to cull badgers (see here), against scientific advice, has ended the honeymoon period for me.