Wednesday, October 11, 2006

Ignorance or Arrogance ?

Our postings below which outline Rosie Woodroffe's 'Letter From America', and blame cattle untested for twelve months for the increase of infectivety found in the RBCT badgers, has provoked a response on the ProMed website from a person involved with bTb 'at the sharp end'. That is, in the field as opposed to behind a computer with a crystal ball and a wish list.

From ProMed:
Date: Tue 10 Oct 2006From: Roy Fey <Roy.Fey@hpa-em.nhs.uk>re: posting 20061005.2857 Tuberculosis, bovine, badgers - UK

"I read the posting and found some of the claims a bit difficult. I am a consultant in communicable disease control (CCDC) with the Health Protection Agency (HPA) in the UK. Part of my training was in Gloucester, which has been a hot-spot for TB (both in cattle and badgers) for many years. Indeed, one might say that the largely successful programs to control TB in cattle after World War II failed in that area (or were never successfully concluded). I recall a vet from the (now) State Veterinary Service (SVS) office in Gloucester explaining that the major differences between the TB they were seeing in badgers and in cattle were:

1) Cattle were captive and being checked regularly, with the result that the reactors were being detected at an early stage of the disease and very few had "open" lung lesions that are necessary for airborne transmission (and none had udder lesions necessary for transmission through unpasteurized milk);

2) Badgers were free ranging and not being checked, with the result that the disease progressed in the badgers to the stage where an infected animal was excreting (in various body secretions, excretions and fluids) vast quantities of bacilli onto the ground/pasture, in their setts, etc;

3) As a consequence, an infected badger was the source for both other sett mates (and other badgers in the area and other animals) and for cattle [A badger sett is a deep burrow that they dig, share with other badgers, and raise young. - Mod.MHJ]. The cattle picked up the germs as they grazed on the infected pasture (and also inhaled germs from the pasture).

Badgers [and possibly other infected wild and domesticated animals: posting 20061009.2896 records "Although called bovine tuberculosis, the bacillus has a broad host range, including cattle, pigs, goats, cats, dogs, badgers, foxes, marsupials, rabbits, sheep, horses and deer. - Mod.LL] also possibly raided stores of feedstuff and contaminated the feedstuff, increasing transmission. In contrast, because most of the cattle were not "open" cases, they were only very rarely transmitting the germ to other animals (including man or badgers).

Clearly, there will be the occasional "open" TB case in cattle, but I must say that, in the past 8 years I have been in my present post, I have only seen one report from the SVS to me in which there have been macroscopic lung lesions (as a proxy, not perfect, I agree, for "open" pulmonary TB) and many hundreds where the skin testing has detected an earlier stage of disease, principally retropharyngeal and mediastinal lymph nodes without lung lesions or even no visible lesions.
[ ................................... snipped]

The conclusions of the report from Dr Woodroffe, that the results clearly show "that there is substantial transmission of TB from cattle to badgers", and "no other explanation fits the data [of an increase in the prevalence of TB in badgers in areas that were left alone during the FMD restrictions]" are not the only logical possibilities and I would contend are not even the most likely explanations."

And with that, we would agree.

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