Saturday, October 24, 2009

And???

This week a new survey was published entitled "Scientific review on Tuberculosis in wildlife in the EU1". This 117 page pdf, gives a thumbnail sketch on the eradication problems in European member states (and other parts of the world) where wildlife reservoirs of TB are proving to be maintenance reservoirs.
"The evidence that badgers transmit bTB to cattle is compelling. Associative evidence includes descriptions of bTB in badger carcases, isolation of the causative organism, surveys where the badger was the only or the principal infected species, road traffic accident (RTA) surveys and statutory badger removal operations.
Laboratory transmission experiments have confirmed that badgers can infect cattle, and badgers are known to excrete M. bovis in faeces, sputum, urine and from open abscesses.
Molecular typing results have demonstrated that badgers and cattle generally share the same spoligotypes in the same geographical locations.
Intervention studies have provided stronger evidence of the direction of transmission between the two species.
Where badgers have been largely removed from areas of persistent cattle bTB infections, the cattle reactor rate has been markedly reduced for a sustained period subsequent to culling.
In recent, scientifically controlled trials, cattle incidence declined in areas where badgers were removed relative to comparable unculled areas.

All very true: this and much more can be downloaded here. We have not ploughed through too much of this because having said badgers are the acknowledged maintenance reservoir of TB in GB and RoI, the authors, many of whom are familiar names on the beneficial gravy train which services bTB, then spend an inordinate amount of time seeking cash for further studies to find out what to do about it. Some things are more than fudged. For instance there is the following all encompassing overview of past culling:
The Eurasian badger has long been implicated as the main wildlife reservoir of bTB in the UK and RoI, and their lethal control has formed an integral part of strategies to reduce bTB in cattle.
So, "lethal control has formed an integral part of strategy" to reduce TB in cattle? That is a remarkable simplification of what has actually happened. and the entirely predictable results of allowing it to happen.

From 1974 there was badger control in response to TB outbreaks in cattle, which could not be attributed to cattle movements. And very successful it was too, bringing the national tally down to less than 100 herds under restriction, and 638 cattle slaughtered in 1986.

But then vote begging politicians, animal lobbyists and other assorted hangers on made their strident voices felt, and policy was loosened to a point where any 'lethal control' was extremely limited and fraught with difficulty. With gassing now replaced by trapping and land available reduced from 7km, to just 1km of land which cattle had grazed, then a rise in cattle sentinels was inevitable. Especially as the authors of the paper observe:
Badger abundance in the UK tends to be relatively high in areas where bTB in cattle is a problem. National badger sett surveys suggested that in some parts of the UK there was a substantial increase in badger abundance between the 1980s and 1990s.
We get the picture - lots of badgers. Thousands of them. A very successful campaign. And dear readers, that 'substantial increase', upon which the authors of the paper have not put a figure, was 77 per cent. Despite this, and despite advice from the old Badger Panel, in 1997 after a £1million bung from the Political Animal Lobby, a moratorium was put on any badger control whatsoever. At that time the number of cattle slaughtered in GB was 3760. The resulting carnage hoovered up 40,000 cattle sentinels a decade later, and we have documented overspill to many other species, some of which are more than capable of sustaining infection within their populations and transmitting it onwards.

Although they have a convoluted way of putting things, the authors of this tome do recognise the dangers:
Research has revealed considerable detail about the ecology, behaviour and population demographics of badgers. Elsewhere in Europe where badger population densities are considered to be generally lower than those in the bTB affected parts of the UK and Republic of Ireland, there have been few confirmed reports of bTB in badgers. Hence, although the risks badgers may pose for onward transmission of bTB to domestic animals elsewhere in Europe are unknown, the evidence to date suggests that they are likely to be lower than in the UK or Republic of Ireland.


Quite. And you propose to reduce this risk, how?

2 comments:

Anonymous said...

There are 117 pages in the EU report - there are 119 references to 'badger' - is there a problem or what?

Matthew said...

Anon 10.25

Dunno. After p.20, (parts of which we have quoted) we lost the will to live.