OrionCA > writes
>On Tue, 6 Jan 2004 08:48:34 +0000, Oz > wrote:
>
>>Now you are being as unreasonable as the rabid veggie activists.
>>There is a very high probability that vCJD is caused by BSE.
>>The emergence, prion typing and the incidence curve are pretty good
>>evidence. Its certainly a sensible modus operandi for public health.
>
>Sorry, but the *proof* would be to demonstrate that

>(a) a large number of people ate "prion-contaminated" beef,

That is beyond dispute for the UK. There are a number of surveys, one by
anderson (oxford university) being the best known. Refs will be in the
BSE progress report previously cited. About 1M subclinically BSE
infected cattle were eaten by the UK population.


>(b) a significant number of these developed the disease, more than
>could be explained away as statistical anomalies,

See onset, rise and decline of vCJD cases. That vCJD derives from BSE is
not proven, but the case is very solid.

>(c) an understanding of the transfer mechanism.

The transfer mechanism, that is oral infection of TE's is hugely well
documented.

>One of the problems with the "pretty good evidence" is that British
>researchers couldn't found "prion contaminated" meat in the markets.

Thats hardly surprising given that the available tests are not sensitive
enough for low levels. Mind you the entire UK vCJD caseload *could* be
explained by rogue butchers and rogue knackers using horribly
contaminated (but apparently wholesome) meat from BSE culls. I strongly
suspect the 'Queniborough hotspot' was caused in precisely this way.
Illegal things do happen. Do not expect to find proof, though.

>Not surprising because these prions are largely confined to the brain
>and, to a lesser extent, its central nervous system. There's also the
>problem of the transfer mechanism being missing: prions do not
>reproduce, neither is there a Xerox "prion copier" in your brain.

Prion precursor (ie the monomer) is produced by the brain, this is not
in doubt. That prions can and will catalyse polymerisation is not in
dispute. Consequently the mechanism is quite clear, and very simple.

>SImply because a *tiny* number of people have a deformed prion
>somewhat similar to one found in BSE-infected cattle doesn't mean the
>people caught it from the cattle. The human eye is exactly like the
>octopus eye in shape and structu Does that make you an octopus?

It makes it an eye. The prions found in vCJD patients typematch that
from BSE and the epidemiology (if it continues to decrease) is also good
evidence. Its more than good enough evidence for me, personally, to
consider suitable precautions to reduce exposure are a very wise thing
to do.

>The final and most important problem is that no one has proven that
>anyone who came down with CJD or a variant thereof ate
>"prion-contaminated" meat. For all we know the disease is actually a
>virus spread by bird droppings and both cows and humans catch it by
>walking barefoot in the fields.

The work on TE transmission has shown that TE's that have a vanishingly
low chance of containing any viable rna or dna are infectious. So this
statement is highly implausible.

>A random Cosmic Ray may zip through
>the skull and deform a prion or two hundred, causing the disease.

Indeed, see sporadic CJD if you like.

>Whatever, the fact that tens of thousands of Brits aren't staggering
>through the streets, foaming and drooling at the mouths (except after
>the pubs close, of course) indicates that whatever causes the disease
>it's far less of a problem than the hysterical rantings of the press
>and advocacy groups would have you believe.

That may be true, but this is because controls were put in place
astonishingly early via southwood.

--
Oz
This post is worth absolutely nothing and is probably fallacious.
DEMON address no longer in use.