Mad Cow Disease now in the U.S.

[Anna N]

It is quite possible that the cow can and will be traced back to Canada but we should keep in mind that just because the cow may have originated in Canada the BSE might not! There's a whole lot more detective work needed here not just to trace the origin of the cow but the origin of all the feed it got throughout its lifetime. Speculation at this time is simply irresponsible.

Furthermore, the incredible panic reaction that is happening now and that happened when Canada first discovered BSE encourages what Premier Ralph Klein called the "Shoot, Shovel and Shutup" way of coping - in other words, the problem goes underground and then we are in real trouble.

Blame is not going to solve the problem. What we need to know is the true extent of BSE in both our countries and I, for one, do not believe it is limited to a single case north or south of the border. If that cow had managed to keep its legs long enough to be slaughtered chances are it would never have been tested.

[Pan]

I'd say there's very little chance indeed that it would have been tested if it had not been a downer. And I wonder just how many downers haven't been tested prior to slaughtering.

[Katherine]

Meat from mad cow sent to 8 states, Guam

In 1997, the United States banned the use of brains and spinal cords, the tissues that carry the disease, in animal feed. But authorities have acknowledged that not all cattle owners followed the rules.

[Nick]

I just came across this interesting bit of info from UPI -

surveys from the USDA's own Food Safety and Inspection Service going as far back as 1997 have found bits of spinal cord -which can carry the mad cow infectious agent - in meat processed by machines called advanced meat recovery systems. The infectious agent, known as a prion, can infect humans and cause a fatal brain-wasting condition called variant Creutzfeldt-Jakob disease.

The spinal tissue was thought to have been introduced into the meat in part due to the routine practice of splitting open the animal's spine during processing. Petersen said the Washington cow's spine had been split open prior to removing it from the carcass.

In 1997, after finding spinal cord tissue in ARM processed beef, the FSIS concluded: "The presence of spinal cord in meat is not expected and cannot be allowed in product produced through AMR systems" due to concerns about transmitting mad cow disease to humans.

The FSIS began to test AMR produced meat for spinal tissue in March of this year after a 2002 survey of 34 establishments producing beef products from AMR systems found that 35 percent of the samples contained spinal cord and other central nervous system-associated tissues such as dorsal root ganglia.

Full article here.

[mb7o]

Fat Guy, if you don't think it's caused by prions, what do you think it is?

I'm willing to grant that Pruisner may spend more time on promotion than research, but as pointed out in some of the links I posted earlier, research on this has actually been going on for the past 70 or more years.

On testing: Here's an interesting comment on some of what's happening in Japan:

http://joi.ito.com/archives/2003/12/28/jap...iseasecase.html

(Basically, like bureaucrats worldwide, proclimations and head-in-the-sand are often acceptable solutions.)

[Pan]

Fat Guy, if you don't think it's caused by prions, what do you think it is?

Of course I can't answer for Fat Guy, but keep in mind that he's not a scientist working on this. But basically, his argument as I understand it is that theories can be and have been disproven before, and this one could be disproven as a result of further scientific studies. Or, I'd add, it could be much more conclusively proven; we just don't know.

[Fat Guy]

Fat Guy, if you don't think it's caused by prions, what do you think it is?

It's not that I "don't think it's caused by prions." What I think is simply that the prion theory is unproven and should be treated as such. Likewise, I think the political commitment to the prion theory has drowned out other legitimate avenues of research that might merit consideration.

One competing theory, which was swept under the rug a couple of years back in the UK, based on the work of Alan Ebringer, professor of immunology at King's College London, is that BSE is caused by bacteria:

"The scientists involved in the research claim that CJD is in fact caused by the body's own reaction to a bacterium found commonly in contaminated water and the soil.

This, they say, would explain such oddities as the fact that one of the victims of nvCJD was a vegetarian.

If they turn out to be right it would mean that the entire campaign to protect consumers by eradicating BSE - costing £3.5 bn, and wrecking the British beef industry - has been wasted."

-- http://news.bbc.co.uk/1/hi/health/345990.stm

Another theory, which accepts the basic prion concept but vastly differs from Prusiner's work, is that of "transition metals," based on the work of David Brown of the University of Cambridge. Here are a couple of pieces of reading on that:

"Brown parts company here with the conventional view, altogether dismissing the notion of an "infectious" prion. He told me: "I have [published] evidence from my cell culture experiments that shows manganese can change the prion into its abnormal [and dangerous] form." This is especially the case when the supply of copper to the cell is low."

-- http://abcnews.go.com/sections/living/Seco...nion010525.html

"[brown] has provided detailed reports to the British government's hearings on mad cow disease and has published several peer-reviewed scientific papers on the subject, including data on how manganese in the environment may play a role in both mad cow disease and vCJD."

-- http://www.open2.net/truthwillout/CJD/article/cjd_brown.htm

An interesting note about the above, even though these reports can be found on the ABC News and BBC Web sites, one rarely sees any mention of any competing theories in the news media's general BSE coverage.

Obviously, I'm not intellectually or academically equipped to develop and test a theory of what causes BSE and CJD. I have to rely on what scientists say, just like everybody else. But I'm also a skeptic, and Prusiner's theories and conduct set off all my skeptic's alarms.

"Prusiner’s thesis about the link between BSE and vCJD is running out of steam. It is now five years since he won his Nobel Prize for claiming that degenerative diseases such as CJD are caused by prions — cell membrane proteins that are found in high concentration in the brain or spine. With the acceptance of his thesis, the scientific establishment threw its weight behind it. Warnings about a possible vCJD epidemic began to proliferate, with the CJD surveillance unit in Edinburgh regularly adding to the grim scenario. Estimates of a death toll of more than 100,000 in Britain were predicted. Yet what is the reality? .... The numbers are, in fact, falling, not rising."

-- http://www.land-care.org.uk/tse/current_to...es_05_12_02.htm

[foodpsycho]

Doesn't CJD supposedly have up to a 30 year incubation period?

[Fat Guy]

Doesn't CJD supposedly have up to a 30 year incubation period?

The theoretical incubation period has undergone a lot of revision over the course of the nvCJD outbreak -- the fact that the number of cases started to decline rather than develop into an epidemic was a big surprise to those who had built models anticipating 100,000 or more deaths. Another issue that came as a surprise was the age distribution of nvCJD vistims: their average age of diagnosis was 28 and there were very few people over 40 diagnosed. The last time I checked in on the mathematical models, the most likely average incubation period was being pegged at 16.7 years.

http://www.pubmedcentral.nih.gov/articlere...gi?artid=156616

[John Whiting]

The most generously financed research projects are those whose unspoken object is to find ways of avoiding BSE while allowing intensive mass-production farming to continue. No instances of BSE-infected cattle have occurred on sustainably run farms with isolated livestock, and it's sophistry to suggest that this is just because the sample isn't large enough.

[jeff29992001]

if prions can pass through the blood-brain-barrier, then that'll give more weight to "infectious prions".

[jeff29992001]

One competing theory, which was swept under the rug a couple of years back in the UK, based on the work of Alan Ebringer, professor of immunology at King's College London, is that BSE is caused by bacteria:

...

http://news.bbc.co.uk/1/hi/health/345990.stm

sorry, the BBC link is 4 years old, and besides that, the autoimmune theory has already been disproven, hence "swept under the rug" as bunk (mouse with no immune system injected with prions can still develop a form of BSE.)

here's this committee take on Ebringer's work....

"Overall the Committee considered that Professor Ebringer supported his theory by using a rather selective and limited choice of publications, and had disregarded much of the published literature. They concluded that the theory was not a good postulate for the origin of BSE and that it did not seriously challenge the prion hypothesis. "

here's a good FAQ regarding BSE in layman's terms.

BSE and vCJD FAQ

Edited December 29, 2003 by jeff29992001 (log)

[Katherine]

Manganese effect on initial generation of prions is interesting, but not a "competing theory", except that the researcher wants to consider it that. It could be complementary, though.

That the prions could spring up where none previously exist might explain some things.

It is, however, irrefutable that feeding infected nerve tissue to beef cattle causes infection. This is something we can't test on people, or at least, shouldn't.

[chezcherie]

This, they say, would explain such oddities as the fact that one of the victims of nvCJD was a vegetarian.

Is this so? I hadn't heard that--can anyone provide a link where I can learn more about this aspect? Thanks.

[Fat Guy]

Search google for "clare tomkins" and CJD and you'll find about a million articles. It's certainly possible that she ate or otherwise ingested some infected byproducts, though.

[chezcherie]

Thanks, FG. I was googling while you were replying, and am now more confused---did find a great number of references to a vegetarian death, along with as many theories as to how this happened (He turned vegetarian at 18, possibly from gelatin, etc...) but this victim was male, and had a Sihk name. Is there a second vegetarian victim? Will google further...interesting thread, to be sure!

[Fat Guy]

"August 22 1997

Michael Hornsby, Times Agriculture correspondent

A YOUNG woman who has been vegetarian for the past 12 years has the new strain of Creutzfeldt-Jakob disease which scientists have linked to "mad cow" disease. The case is highly unusual because the first clinical case of BSE was recorded in cattle only in 1986 -- a year after Clare Tomkins, now aged 24, stopped eating meat."

-- http://www.mad-cow.org/~tom/veg.html#Vegetarian

[chezcherie]

The name of the other victim was Jorawar Gill, and apparently both "vegetarian" victims had eaten beef on an unknown number of occasions.

[Katherine]

I also saw a reference to the fact that three victims were gardeners who (presumably?) used bone meal in their hobbies.

[ankomochi]

US Officials went to Tokyo to beg for Japanese gov't to resume the import of US Beef.

http://home.kyodo.co.jp/all/display.jsp?an=20031229210

[R Washburn]

The prion theory has achieved dominance of late, but is still a theory. I wonder how history will judge it: brilliant scientific analysis, or our generation's equivalent of phlogiston.

Shaw, the evidence for prions is at least as strong as the evidence that HIV causes AIDS. The whole idea of infectious protein (which has even been found in Yeast) was so revolutionary that the resistance against the idea has been extreme.

In fact, the only way I can see to protect our beef supply 100% from BSE is to develop a genetically modified cow that has the gene for Prp deleted. This has already been done in mice and results in a viable animal that is incapable of being infected by prions.

[tryska]

In fact, the only way I can see to protect our beef supply 100% from BSE is to develop a genetically modified cow that has the gene for Prp deleted. This has already been done in mice and results in a viable animal that is incapable of being infected by prions.

this an even scarier notion than cannabilistic cows.

[R Washburn]

this an even scarier notion than cannabilistic cows.

Why do you find genetically altered cows scary? I don't think there is much chance of us accidentally developing a "super cow" and having it take over the world.

The whole "Mad cow" hysteria just underscores the inability of people to assess risk. Even in the UK, with its long history of scrapie (the sheep equivalent, and likely source of BSE), there has only been a handfull of human cases of BSE. Our beef supply must be hundreds if not thousands of times safer then Britain's, yet people here are terrified of Mad cow. Personally, I am a lot more concerned about getting a lethal case of hepatitis from my green onions or catching Legionaire's disease from breathing to close to the mister in my local supermarket. Those are statistically much more serious, and immediate, threats.

[tryska]

this an even scarier notion than cannabilistic cows.  

Why do you find genetically altered cows scary? I don't think there is much chance of us accidentally developing a "super cow" and having it take over the world.

well - going back to chaos theory - by making even a minute change to the natural order of things you can expect the unexpected. i'm not a big fan of tinkering with the works of Mother Nature, as it were.

altho granted some of our tinkering has come out well, such as this medioum of communication here - quite a few haven't come out so good.

penicillin, for example. it was a brilliant discovery and it saved lots of lives....of course the flip-side now is that we've got these drug-resistant superbugs.

Edited December 29, 2003 by tryska (log)

[R Washburn]

well - going back to chaos theory - by making even a minute change to the natural order of things you can expect the unexpected. i'm not a big fan of tinkering with the works of Mother Nature, as it were.

So you don't think civilization is a positive thing? Controlling and altering Nature is what Man is all about.