PDA

View Full Version : Deer, Elk, TSEs & Chronic Wasting Disease


Welcome to the Active Low-Carber Forums

Support for Atkins diet, Protein Power, Neanderthin (Paleo Diet), CAD/CALP, Dr. Bernstein Diabetes Solution and any other healthy low-carb diet or plan, all are welcome in our lowcarb community. Forget starvation and fad diets -- join the healthy eating crowd! You may register by clicking here, it's free!



su-texas
Wed, Dec-04-02, 23:55
Today, I read an article in a magazine about CWD, & it sounds
like very scary stuff.

-------------

From: The Rock Garden (hensler@povn.com), Subject: CWD
article, Newsgroups: misc.rural, Date: 2002-11-30 11:05:49 PST

For those interested, there is a current article on Chronic
Wasting Disease in the Milwaukee Magazine on line at
http://www.milwaukeemagazine.com/122002/cwd.html It is long
and the slant in on the Wisc. deer herd, but is fairly well
researched and written in non-technical terms. Skip

-----------------

From: Thundercleese (dan@angband.org), Subject: Re: CRUISE
VIRUS- WHAT THE H... IS GOING ON?, Newsgroups: rec.boats,
Date: 2002-12-03 22:20:06
PST

Also Sprach Floyd in Tampa <Flooydomit@prodigy.net>:
> I'm not a vector specialist, but watching the crew rubbing >
> the ship
down with rags seems laughable, and what could > they possibly
be spraying that would affect a virus?

Most likely dilute chlorine bleach. Virii are pretty weak,
when outside a host. Now you want a tough infectious agent,
look at prions. Basically a distorted protein molecule, can
survive autoclaving, exposure to vacuum, and all kinds of
chemicals. They cause the Mad Cow Disease, Chronic Wasting
Disease, and Creutzfeldt-Jakob Disease (the human Mad Cow).
CJD has been transmitted to surgical patients from
contaminated surgical instruments even though they had been
cleaned and autoclaved. Scary stuff. Dan

---------------

Susan, Su_Texas my opinions

PP Some quotes from the article mentioned above:

If you ask the country's highest-ranking experts on prion
diseases like CWD, mad cow and human Creutzfeldt-Jakob disease
(CJD), they will tell you that only incineration, bleach and
chemical tissue digestors destroy the infectious agents that
cause the diseases and that serious public concern is
warranted.

"We have repeatedly underestimated these diseases, and we've
been wrong. People have died because of it," says Judd Aiken,
UW animal health and biomedical sciences researcher. "I'm not
an alarmist and I don't like having people mad at me, but it's
the truth when I say don't consume venison from an area where
CWD exists."

The group urged the state to adopt the steps Britain has taken
to stop mad cow disease and immediately ban venison handling
by meat processors who also prepare beef, chicken and other
meats. The nearly indestructible CWD disease prions, it said,
could contaminate equipment and pass into the rest of the food
chain. "People have the right to decide for themselves whether
they want to eat venison," says Olds. "They shouldn't have to
worry that other meat they eat is contaminated."

-------

Like elk, deer can carry the disease for years without
symptoms, infecting other animals. Until just recently, there
was no live-animal CWD test.

Symptoms: It takes an average of 15 months for a deer infected
with CWD to exhibit symptoms, but they can occur in as little
as six months or not show up for as long as eight years, says
Hauge. Then it will display abnormal behavior, stupor, head
tremors, staggering, lack of coordination, trouble judging
distance and difficulty swallowing. CWD-infected deer drink
lots of water, increasing urination, and slobber excess
saliva. They "waste away" until paralysis or pneumonia set in.
"It is not a pretty death," says Hauge.

Spread: Scientists believe nose-to-nose contact spreads CWD,
as well as environment and food contaminated by saliva, urine
and feces and by does who infect their offspring.

--------------

CWD's Family Tree

When Richard Race (a leading researcher on CWD and related
diseases with the National Institutes of Health's Rocky
Mountain Laboratories), heard Kazmierczak's comment about
eating deer brains, he was appalled. "That's irresponsible. Do
we want to have a repeat of what happened in Britain, where
for 10 years the government said BSE [mad cow disease] was
safe to eat, and so far we have 133 people dead because of
it?" asks Race. "It's not fair to say people either are or
aren't susceptible to CWD at this point. Not enough people
have eaten enough infected venison and lived long enough for
it to incubate."

TSEs & Chronic Wasting Disease in Deer (CWD): Researchers who
saw the first cases of CWD in Colorado deer in 1967, thought
it was a nutritional problem. By 1980, they realized it was
part of a family of deadly neurological disorders called
transmissible spongiform encephalopathies (TSEs), affecting
humans, sheep, mink, cats and other animals.

TSEs & Mad Cow Disease (BSE): The most famous TSE of all,
bovine spongiform encephalopathy (BSE), appeared in Britain in
1985. It killed nearly 200,000 cattle, then spread to humans
who consumed infected beef.

TSEs & Prions (Infectious Protein): Unlike most diseases,
which are caused by viruses or bacteria, the infectious agent
in TSEs is believed to be a normal protein that mutates,
becoming an infectious protein, or prion, and then causes the
misfolding of other proteins. The process creates sponge-like
brain lesions leading to physical and mental decline.
Although human cases are rare, TSEs are so significant that
two Nobel prizes for medicine have been awarded for prion
disease research.

-----------

When mad cow disease first appeared, officials said it was
"just like scrapie in sheep", the oldest known TSE, never
known to have infected humans. The disease is called scrapie
because infected sheep become so deranged, that they rub
themselves raw attempting to scrape off their fur.

The Spread of TSEs, From Sheep to Deer to Elk?: There is
unproven speculation that CWD originated when environmental
contamination passed scrapie from sheep to deer housed at
Colorado State University's Foothills Research Station, then
to wild deer and elk. That's one reason Wisconsin officials
say CWD is like scrapie. Of course, that's what the British
government thought, too, while nearly two million contaminated
cattle slipped into the human food chain.

TSEs in Cats: For more than a decade -- even after cats fed
infected beef meat and bone meal came down with a mad cow-like
disease -- the British government insisted that human beef
eaters were protected by a "species barrier."

Five years after some physicians and scientists started
sounding alarms about eating infected beef, then British Prime
Minister John Major was still reassuring the public: "There is
no scientific evidence that BSE can be transmitted to humans."

TSEs & Creutzfeldt-Jakob Disease in Humans (CJD): [In about
March 1996,] two dairy farmers, a butcher, a meat pie maker
and eight young people who had eaten contaminated beef were
dead from an Alzheimer's-like disease called new variant
Creutzfeldt-Jakob disease (nvCJD). It looked similar to the
rare sporadic CJD that affects only one person per million,
but when their brains were autopsied, they looked just like
the brains of mad cows. The government finally admitted
that the "species barrier" -- if it existed at all -- had
holes in it.

---------

TSEs Spread Through Meat: The World Health Organization now
says mad cow disease passed to humans when they ate infected
beef. Hamburgers and processed meats like sausage that
included bovine offal (by-products) -- brains, spinal chords,
eyes, lymph nodes, thymus and intestines -- areas with the
highest concentration of disease prions, are the chief
suspects, although laboratory scientists have since found TSE
disease agents in blood and muscle, too.

(Dr. Olds says Wisconsinites should forgo venison sausage even
if deer offal is left out and their deer tests negative
for CWD because there is no guarantee their deer won't be
mixed with others in the sausage-making process.)

No one knows how much infected meat you'd have to eat to get
new variant CJD or even whether a little now and then will
add up to infection. But as little as one-half gram of
BSE-infected brain -- the size of a good vitamin pill --
taken orally will infect a cow, NIH senior prion disease
researcher Paul Brown told the FDA's TSE Advisory Committee
on January 19, 2001.

Cooking at temperatures above 600 degrees C doesn't kill the
infectious agent in TSEs, nor do detergents and enzymes known
to kill most viruses. Radiation doesn't faze it, and even
after being buried in the soil for three years, enough prions
remain to spread the disease. Chlorine bleach is one of the
better disinfectants, in concentrations of 50 percent and
higher, but sometimes even that has diminished effectiveness.

Beef by-products are now banned from human consumption in
Europe (though not in the United States), but since human TSEs
incubate for decades, no one knows what the final human death
toll will be.

------------------

Autopsies: It's difficult to find a neurologist like Antuono,
willing to autopsy the brain of a patient suspected of dying
of a TSE. A splash in the eye of bodily fluid can carry the
disease straight to the brain.

Those who have already died shared one of three genetic
variations for the human prion protein, a genetic make-up seen
in 40 percent of the population. But "that doesn't mean others
are immune," says UW's Aiken. The disease may merely incubate
longer in people with other genes.

Research published in May 2000 in The European Molecular
Biology Organization Journal states: "CWD transmissions would
be similar to transmissions of mad cow disease," adding that,
"it would seem prudent to take reasonable measures to limit
exposure of humans (and cows and sheep) to CWD infectivity."

--------------

Wisconsin's TSE History

TSEs & Alzheimer's?: The original human TSE, classic
Creutzfeldt-Jakob disease, is often mistaken for Alzheimer's,
but it is a rare nervous system disease that results in
rapidly progressive dementia, a nightmare of madness and
terrifying hallucinations, loss of motor control, paralysis
and death.

Discovered in the 1920s, it seems to occur spontaneously
across the globe (300 per year in the United States),
attacking victims with a mean age of 68. Scientists refer to
it as "sporadic CJD." Another extremely rare type of CJD
occurs in families.

TSEs & Kuru: But in the 1950s, a human TSE called kuru was
discovered among the primitive Fore people of New Guinea, and
it was epidemic. American researcher Carleton Gajdusek
received the Nobel Prize in 1976 for showing that kuru was
spread by the Fore's ritual cannibalism of deceased
relatives, including eating the brains of those who died of
kuru. From kuru, scientists learned that a human TSE can
incubate 10 to 40 years.

------------

TSEs/TMEs in Mink: Transmissible Mink Encephalopathy, a
related disease, has a long Wisconsin history. Four of the
five known U.S. outbreaks since 1947 have occurred here. The
first killed every mink on the affected Wisconsin ranch.

TSEs/TMEs in Raccoons & Monkeys: In 1969, the late UW-Madison
researcher Dick Marsh discovered that TME could be transmitted
to raccoons and monkeys in the lab.

By the mid-1980s, both Marsh and Nobel laureate Gajdusek
believed all TSEs were really one disease altered by the
passage from one species to another, and that a single TSE
could have multiple strains that act differently.

(The CWD in Wisconsin and the CWD in Western states may turn
out to be distinct strains, but at present, scientists are
applying the little they know about the Western disease to
Wisconsin.)

TSEs in Mink & Cows: When mink TSE wiped out 60 percent of the
7,300 breeding mink on a Stetsonville, Wisconsin, ranch in
1985, Marsh traced the disease to the mink's feed, downer
dairy cows (cows unable to walk and considered unfit for human
consumption). Marsh injected some of the infected mink tissue
into the brains of two calves and waited. In less than two
years, the calves' rear legs collapsed under them just like
downer cattle. He injected some of the calves' brain tissue
back into healthy mink. After an incubation period identical
to that in the original infected mink, the new mink developed
the same disease.

Concluded Marsh: "If spontaneous cases of prion diseases can
occur in humans, they likely also occur in animals. Not
naturally transmitted to other members of the species, these
spontaneous incidents can still pose a danger because of the
unnatural act of cannibalism, as seen in kuru in humans or...
the feeding of animal protein produced by rendering ruminants"
back to other ruminants (sheep, cows, elk, goats and deer). In
effect, the then common practice made herbivore cattle into
cannibals. In 1995 alone, DNR records show that 26,488
road-killed Wisconsin deer were rendered into feed.

No case of mad cow disease has ever been confirmed in the
United States, but Marsh urged the USDA to ban the practice of
feeding processed bone and blood meal made from rendered
sheep, cows and deer to other ruminants. His suggestion would
have cost the agricultural industry dearly in substitute
protein, and the USDA took no action.

-------------

Frustrated, in 1993, Marsh repeated his concern in the state
Agri-View, warning Wisconsin dairy farmers they were feeding
cattle to cattle. He also talked to The New York Times.
Marsh's published comments ignited such a torrent of
complaints from the state's agri-business industry, which
underwrites much of the UW Agriculture School's research, that
the college's dean tried to silence Marsh.

Marsh was harassed and threatened with lawsuits, and the
university sponsored a symposium "whose only purpose seemed to
be arguing there was no need to change animal feeding
patterns," recalls Aiken, then a Marsh colleague, as was
Olander. (Both joined Marsh in pushing for a broad
ruminant-to-ruminant feeding ban.)

Marsh was "not allowed to speak, while everyone discredited
his work," says John Stauber, executive director of the
Madison-based Center for Media and Democracy, who dedicated
his book, Mad Cow, USA, to Marsh.

Despite the humiliation inflicted by the university, Marsh
would be vindicated. When protein feed from rendered downer
cows and scrapie sheep was identified as the cause of mad cow
disease in Britain in 1996, the university lionized Marsh in
its Wisconsin Alumni Magazine as the scientist who'd predicted
the disaster and tried to stop it.

"We were inundated. We had over 200 phone messages from CBS,
NBC and other people in the media who wanted to talk to
Dick," remembers professor Bruce Christenson, Marsh's
successor as chair of the department of animal health and
biomedical sciences. But by then, Marsh, 58, had cancer,
recalls Christenson. "He was a warrior even when he knew he
was dying."

-----------

su-texas
Thu, Dec-05-02, 13:58
The Lack Of Testing, Diagnosis, & Care

Most doctors won't test for diseases, injuries, etc., for
which they can't sell a standard-type & very-expen$ive product
& treatment, ... & some docs refuse to do any testing. Many
doctors refuse to refer their clients to competent/intelligent
specialists.

The wont-work docs seem to be satisified/content with the
money they can take, by selling their "time" (which is usually
worthless), & by overly-pushing/selling the BS/harmful-type
medicines, such as tranquilizers & the very misnamed
"antidepressants". Nothing could be more depressing, than
being delayed/prevented from reaching any good/competent
medical care, & being repeatedly conned/tricked & sold the
expen$ive & harmful BS-type medications.

This might be true for TSEs also. So far, most doctors won't
test for, acknowledge, or treat it. They are probably
mislabelling it, as being Alzheimer's, Parkinson's, Chronic
Fatigue Syndrome, Lyme Disease, etc. And the worst docs will
continue to overly-push those standard-type, expensive, BS
medicines/drugs, ... for TSE conditions & for almost
anything/everything else, ... which can do so much harm
(physically, financially, & mentally/emotionally).

This BS-type practice of medicine, very harshly ruins/destroys
lives, families, careers, resources/assets, & hope.

If diseases would be tested for & diagnosed by doctors, then
this could force the treatments & cures for these diseases, to
be quicker in coming. It could also help with warnings & with
preventing transmission to others.

I have read that there is now a test for CWD/TSEs on live
animals, & I am trying to find more information about this.

Susan, Su_Texas my opinions

su-texas
Fri, Dec-06-02, 13:57
New Tests For TSEs & Prions: CJD, CWD, BSE, TME, scrapie, etc.

CDI (Conformation Dependent Immunoassay), Stanley Prusiner,
University of California in San Francisco

[General Search http://www.google.com/search?q=cjd+cdi+disease
, Search Terms: CDI, Disease, CJD]

-----------

[The following quotes are from the post & article
mentioned below.]

Prusiner said that part of the problem could be traced to
existing tests for the existence of prions in animals or
humans. 'These tests chew up prion molecules in such a way
that means we fail to spot them. We were destroying critical
evidence of infections, perhaps up to 99 per cent of
it. It is very serious.'

As a result, he and his colleagues have perfected a new
technique for detecting prions in samples, one that is
10,000 times more sensitive than existing tests used in
Europe and America.

The new test - conformation dependent immunoassay (CDI) -
works on a completely different principle. Essentially, it
recognises the shape of prion molecules. 'We believe that by
applying the test to cattle we should significantly reduce
human exposure to bovine prions,' said Dr Jiri Safar, one of
Prusiner's colleagues.

'Previous attempts to quantify BSE and scrapie prions in milk
or non-neural tissue, such as muscle, may have underestimated
infectious titers [levels] by as much as a factor of 10,000,
raising the possibility that prions could be present in
sufficient quantities to pose risk to humans. The high
sensitivity of this new test may profoundly alter our view of
the epidemiology of prion diseases.'

-------------

From: torresD (torresD30@hotmail.com), Subject: Eating meat
'may still pose CJD risk', Newsgroups:
soc.culture.puerto-rico, soc.culture.cuba,
soc.culture.latin-america, Date: 2002-12-03 23:00:10 PST

http://www.observer.co.uk/uk_news/story/0,6903,851481,00.html

Eating meat 'may still pose CJD risk', Robin McKie, science
editor, Sunday December 1, 2002, The Observer

[Muscle Meat, TSEs, & Prions]

Muscle and flesh of cattle and sheep may harbour deadly levels
of prions that cause variant CJD. This stark prospect, raised
by the Nobel Prize winner who first discovered that these
infective particles can cause brain illnesses, suggests eating
meat may still pose a serious health risk.

The prospect that a timebomb may still be ticking in our
kitchens was raised by Stanley Prusiner, who revealed
yesterday that experiments at the University of California in
San Francisco had shown that scrapie-infected mice have
unexpectedly high concentrations of prions in their muscles.

'These are just mouse models, but they raise the obvious worry
that cows and sheep could be similarly affected,' said
Prusiner, who received the 1997 Nobel Prize for medicine for
discovering that degenerative brain diseases such as
Creutzfeldt-Jakob Disease are caused by prions.

Until now, scientists had assumed that only brains and spinal
columns of cows and sheep contain dangerous levels of prions.
But it appears that cuts of beef and lamb, which largely
consist of muscle, could also be affected.

'The levels we found were a hundredfold less than those found
in brains, but were still significant,' he said. 'In
particular, we found that the hind legs of mice had high
numbers of prions. It remains to be seen if that is mirrored
in the hind legs of cattle or sheep.'

--------------

Susan, Su_Texas my opinions

su-texas
Sat, Dec-07-02, 13:57
Blood Tests For TSEs in Live Animals

ICE Test (an immunoassay using capillary
immuno-electrophoresis, capillary immunoelectrophoresis), is a
Blood Test for TSEs in Live-Animals.

Mary Jo Schmerr Lead Scientist, Prion Diseases Research Unit
National Animal Disease Center United States Department of
Agriculture (USDA) Agricultural Research Service Ames, Iowa

[General Search
http://www.google.com/search?q=Mary-Jo-Schmerr ]

-------------

The Need For Better Blood Tests

Blood Transfusions: It's very important to develop good blood
tests for TSEs & prions, so that human blood can be tested for
this, before being used in transfusions.

Better Medical Treatments & Care: If variant CJD can be
tested for & found early, it can probably be
more-successfully treated.

More Accurate Diagnosis & Reporting of Cause of Death: The
correct/actual cause of death, is often not tested for or
known here in East Texas. The doctors just write something. If
there were better testing & diagnosis, then there could be
better reporting & awareness of diseases such as variant CJD,
... instead of its being mislabelled as Alzheimer's, etc.

Safer Food Supply, & Sparing the Lives of Some Pets &
Wildlife: With better blood testing methods for prions & TSEs,
live animals can be tested for these, rather than their having
to be killed & autopsied.

People have been reported to have possibly contracted their
TSEs, from preparing and/or eating animals such as beef, deer,
elk, squirrels. This infection can happen, through cuts &
scratches during food preparation, through residues left
behind, or from eating the prepared food.

TSEs might also be present in pigs & hogs, but these animals
are often slaughtered before the disease can begin to show its
outward symptoms, at 24(?) months of age. Also, at the time of
slaughter, the symptoms of TSEs are usually Not being looked
for, in pigs.

--------

Susan, Su_Texas my opinions

su-texas
Sat, Dec-07-02, 13:57
Killing Prions On Surgical & Dental Instruments: Strong Bleach
Solution (for 24 hours?), & One-Hour Autoclave Treatment =A0
author:iayork@panix.com prions,=A0From: Ian A. York
(iayork@panix.com), Subject: Re: Will heat destroy mad cow
preons?, Newsgroups: sci.med, Date: 1996/05/15

.. Here is a post I've made previously about prion stability.
The quotes are taken taken from articles I found on a Medline
search, but for some reason I failed to cite them:

Standard approaches, such as 10% hypochlorite (bleach) and
standard autoclaving time are Not completely effective: some
scrapie agent survives an hour of autoclaving, and a year
(sic) of 10% hypochlorite treatment.

Higher concentrations are pretty good: "no standard chemical
or physical decontamination procedure will reliably inactivate
the amount of scrapie/BSE infectivity present in worst-case
situations, but high concentrations of sodium hypochlorite or
sodium hydroxide have been shown respectively to be completely
effective or almost so."

Autoclaving is actually much more than 99% effective, if done
for longer than an hour. The number of infectious particles
can be reduced by 10^3
- 10^7 (depending on the strain). It is also quite effective
(reduction of titer by >10^6) if done at higher than normal
temperature - at 136 oC
>rather than the usual 126 oC.

So to put some percentages on this, a high-titered infectious
hamster brain can have 10^10 (10,000,000,000) infectious
particles. If you hit this with a treatment - say, bleach -
that reduces infectivity by
99.99%, you're left with a mere 10^6 infectious particles, and
who's going to worry about a million here or there? Well,
okay, if you're going to be picky, then let's autoclave it
at 136 oC and reduce the titre by 99.99999%, which will
leave you with just 1000 infectious particles floating
around. You see the problem?

The bottom line is that there are never absolutes - nothing is
ever completely effective in anything; this shows up a little
more pointedly in the prions than with most of daily life.

The other point I made about the rendering process, is that
there is a definite species barrier to prions (all that are
known); you can, for example, use scrapie agent to infect
mice, but to do so the first time take a lot more scrapie
agent and lot longer for the disease to show up.

Thus the term "one infectious particle" isn't really
meaningful in the context of interspecies transmission. You
can take a glop of prions and say "This has 10^10 infectious
particles", because there might be enough there to infect
10^10 mice (theoretically; not in practice, because you don't
usually have a linear slope on your infectivity curves once
you reach lower titers); but that same glop might have 10^5
infectious particles for sheep and 10^2 infectious particles
for cattle, and 1 infectious particle for man.

I'm sort of eliding all sorts of points here, but I think you
should get the gist, anyway. -=3D-=3D-=3D- Ian York
(iayork@panix.com) <http://www.panix.com/~iayork= />

---------

----------

From: Teresa (ctfedor@homesweethome.com), Subject: Re:
Surgical instruments spreading brain wasting disease,
Newsgroups: alt.true-crime, Date: 2001-03-24 17:44:06 PST: ..
I had no idea that any kind of pathogen could survive the
sterilization process that is normally used on surgical
instruments.

As it turns out, prions that cause Creutzfeldt-Jakob disease,
are not killed by steam sterilization, thus instruments used
on a patient with this disease are capable of spreading the
disease to every person who undergoes surgery with the same
set of instruments.

Teresa - wondering how these prions can be killed?

Well, I found the answer to my question. In case anyone else
here is interested, here it is:

------------

<quote> Table C Effective Prion Deactivators

Autoclaving @ 134C/275F for One Hour

Cleaning Instruments and Equipment with 2.5-5% NaHypochlorite
for 24 Hours.

Incineration

1MNaOH, 24 Hours (ANA Recommendation)

3-6 Guanidumiun Isothiocynate (3M 24 Hours; 4M 1 Hour; 6M
15 Minutes)

Boiling 3% NaDODECYL SULFATE (SDS) 10 Minutes

(Robert-Koch Institute, 1996)

Because the TSEs present such unique and unconventional
challenges for containment, decontamination, and
sterilization, careful planning is required in preparation for
invasive procedures to be performed on these patients.

The College of American Pathologists recommends that all brain
biopsies for dementia should be handled as possible CJD cases.
(Crain, 1998) That recommendation should be the first criteria
stated in a policy and procedure for case containment of
suspected CJD cases.

Table D is a consolidation of recommendations found in current
literature for case containment in suspected CJD cases.

--------

Table D

Recommendations for Case Containment of Suspected
Creutchfeldt-Jakob Patients .

Surgery Room Preparation:

Remove all unnecessary equipment Use as many disposable items
as possible Use disposable linen Close and seal all room
cabinets Schedule the case as the last case of the day
Intra-Operative

Do Not use Gas Sterilizable Only Instrumentation Irrigate any
Percutaneous Exposure to Fluid and Tissue with 0.5% Bleach
Use Outside Circulator to Obtain Needed Supplies Use of Power
Instrumentation is NOT Recommended Use Waterproof Shoe Covers
and Remove Before Leaving Room

------------

Post-Operative:

Clean All Instruments in the OR Suite using usual Cleaning
Products Sterilize Instruments in the Substerile Room

Autoclave as follows: Gravity Style Autoclave: 132*, 60
minutes Prevacuum Style Autoclave: 134*C 18 minutes

Following Initial Sterilization, instruments can be
returned to the Central Processing Unit for the usual
decontamination process:

Decontamination in the washer/sterilizer/decontaminator
Assembly and wrapping Terminal Sterilization

Fluids: All fluids in the room should be treated with
bleach and disposed of according to local health codes. If
fluids are disposed of in a hopper, care must be taken to
avoid aerosols during the flush cycle and the hopper must
be thoroughly cleaned with bleach following the flush
cycle. Some recommend that liquids be incinerated,
including wash water.

All room surfaces and equipment must be wiped down with bleach
or Sodium hydroxide after the procedure. This may require
specially trained staff since these are hazardous materials.

Although the main focus of this article is for nursing care
and concerns for the patient suffering from CJD, this author
believes that the policy and procedures for this disease needs
to be comprehensive.

--------

Table E is summation of CJD recommendations from the
College of American Pathologists (Crain, 1998). (Click
here to download a copy of Table E separate from this
article) <unquote>

Teresa

----------

-----------

In 2002, the guidelines might be more stringent/strict, now
that there is more information available about the possible
transmissions of TSEs (such as certain forms of CJD & BSE),
... from animals to animals, from animals to humans, & from
humans to humans.

Susan, Su_Texas my opinions

Elzinator
Sat, Dec-07-02, 13:57
On Sat, 7 Dec 2002 08:09:21 -0600 (CST),
su-texas@webtv.net wrote:
>Killing Prions On Surgical & Dental Instruments: Strong
>Bleach Solution (for 24 hours?), & One-Hour Autoclave
>Treatment
<snip?
>
>In 2002, the guidelines might be more stringent/strict, now
>that there is more information available about the possible
>transmissions of TSEs (such as certain forms of CJD & BSE),
>... from animals to animals, from animals to humans, & from
>humans to humans.

I conduct research in a biosafety level 2-3 facility and we
process suspected prion-containing tissues for histopathology
(in cooperation with a prion lab next to ours). We use NaOH
for disinfection.

From federal guidelines:

"Physical properties of prions. The smallest infectious prion
particle is probably a dimer of PrPSc; this estimate is
consistent with an ionizing radiation target size of 55 ±9
kDa.(30) Therefore, prions may not be retained by most of the
filters that efficiently eliminate bacteria and viruses.
Additionally, prions aggregate into particles of non-uniform
size and cannot be solubilized by detergents, except under
denaturing conditions where infectivity is lost.(31)(32)
Prions resist inactivation by nucleases,(33) UV-irradiation at
254 nm,(34)(35) and treatment with psoralens,(36) divalent
cations, metal ion chelators, acids (between pH 3 and 7),
hydroxylamine, formalin, boiling, or proteases.(37)(38)

Inactivation of prions. Prions are characterized by extreme
resistance to conventional inactivation procedures including
irradiation, boiling, dry heat, and chemicals (formalin,
betapropiolactone, alcohols). While prion infectivity in
purified samples is diminished by prolonged digestion with
proteases,(39)(40)results from boiling in sodium dodecyl
sulfate and urea are variable. Sterilization of rodent brain
extracts with high titers of prions requires autoclaving at
132C for 4.5 hours (h). Denaturing organic solvents such as
phenol or chaotropic reagents such as guanidine isothiocyanate
or alkali such as NaOH can also be used for
sterilization.(41)(42)(43)(44)(45) Prions are inactivated by
1N NaOH, 4.0 M guanidinium hydrochloride or isocyanate, sodium
hypochlorite (2% free chlorine concentration), and steam
autoclaving at 132C for 4.5 h.(46)(47)(48)(49) It is
recommended that dry waste be autoclaved at 132C for 4.5 h or
incinerated. Large volumes of infectious liquid waste
containing high titers of prions can be completely sterilized
by treatment with 1N NaOH (final concentration) or autoclaving
at 132C for 4.5 h. Disposable plasticware, which can be
discarded as a dry waste, is highly recommended. Because the
paraformaldehyde vaporization procedure does not diminish
prion titers, the biosafety cabinets must be decontaminated
with 1N NaOH, followed by 1N HCl, and rinsed with water. HEPA
filters should be autoclaved and incinerated."

HTH.

Elzi

Bioinformatics: "What is a sheep; only millions of little bits
of sheepness whirling around and doing intricate convolutions
inside the sheep? What else is it but that?" -Flann O'Brien,
"The Third Policeman"

Hua Kul
Sat, Dec-07-02, 23:56
su-texas@webtv.net wrote in message news:<5958-3DF224F3-245@s-
torefull-2136.public.lawson.webtv.net>...
> Thanks, Elzi/Elzinator.
>
> I am trying to learn more about the subject of TSEs, using
> my very limited knowledge & internet research skills,

Susan, here is an interesting counterpoint to the infectious
theory of spongiform encephalopathies. Mark Purdey believes
that these diseases are caused by a combination of
organophosphate exposure and high dietary levels of manganese.
He has found pockets of these diseases worldwide and has
correlated possible dietary factors. It should be interesting
for your research. http://www.markpurdey.com/

--Hua Kul

Hua Kul
Sun, Dec-08-02, 06:55
su-texas@webtv.net wrote in message news:<5958-3DF224F3-245@s-
torefull-2136.public.lawson.webtv.net>...
> Thanks, Elzi/Elzinator.
>
> I am trying to learn more about the subject of TSEs, using
> my very limited knowledge & internet research skills,

Another link to Mark Purdey information.
http://www.purdeyenvironment.com/

--Hua Kul

Elzinator
Sun, Dec-08-02, 20:58
On Sat, 7 Dec 2002 10:42:27 -0600 (CST),
su-texas@webtv.net wrote:
>Thanks, Elzi/Elzinator.
>
>I am trying to learn more about the subject of TSEs, using my
>very limited knowledge & internet research skills, so I'm
>sure I'll get lots of information wrong. I am hoping to post
>what I can find, that seems relevant & somewhat reliable
>about TSEs, ... in order to pass on this info to the general
>public, & thereby open it up for more discussion & interest.
>More people can then put pressure on politicians for positive
>changes. What we're still hearing, is that there's no BSE in
>the USA, which seems to be a total crock, a lie.
>
>If the TSEs can be tested for in live-animal/human blood, &
>if this epidemic can be contained more quickly &
>efficiently/effectively, then the spread can be better
>controlled, & the victims of this disease might get more
>validation & information quicker, & better medical care.

The problem is lack of reliable and rapid testing techniques.
To date, the only reliable assay is with brain tissue, which
obviously, has limitations. Researchers are devoting much
resources to developing more rapid and reliable assays for
live animals/humans, but that is still some time away. Until
such an assay is developed and tested to be reliable, control
policies are limited. There is still much we do not know.

>Rendering Plants: One of the main ways of spreading TSEs to
>animals, seems to be through the use of protein products
>(from rendering plants) in livestock & pet foods.
>
>From what I've read, these rendered-protein-products are
>being fed to chickens & pigs, ... & then the parts & waste
>from chickens & pigs, are being fed to cows, etc., ... in
>order to get around the current FDA rulings which state, that
>cows can't directly be fed cow parts & waste. And the
>chickens & pigs are Not being tested for TSEs.
>
>This is a cycle which seems guaranteed to promote & quickly
>spread diseases such as TSEs.

Regulations against feeding animal parts in livestock
production have been in place for many years now. Even the
methods used to kill meat animals for public consumption have
been changed and regulated to reflect advances in prion
research and to reduce the risk of contamination and
transmission as much as possible. And it will continue to
change as research reveals more about the disease and its
transmission.

Also, new research continues to mount regarding other forms of
CJD in humans that were previously thought to be unassociated
with BSE. I pasted in a post I made yesterday concerning a
recent study.
-----------------------------------------------------
E.A. Asante, JM. Linehan, M. Desbruslais EMBO J, Vol. 21, No.
23 pp. 6358-6366, 2002. BSE prions propagate as either
variant CJD-like or sporadic CJD-like prion strains in
transgenic mice expressing human prion protein.

There are several types of CJD that are distinguished by the
cause of the disease. Variant CJD (vCJD), reported in 1996, is
thought to be caused by exposure to BSE-like prions; whereas
classical (sporadic) CJD, the most common form, is thought to
be caused by a spontaneous change (a random chance event) of
the prion protein (PrP) in the brain to the abnormal form (PrP
sc). However, the exact cause of sporadic CJD has not yet been
explained, although previous work (in 1996) showed that a
characteristic molecular signature was associated with the BSE
and vCJD diseases. This signature was different than that of
sporadic CJD.

There are four known types of the disease-causing prion
protein (PrP sc), based on conformation (i.e. folding) of the
protein, that may be important in transmission, host
specificity (species barriers), and disease progression. Three
of these (types 1-3) have been associated with classical CJD,
and type 4 with vCJD.

(for more information on prion conformation: http://www.esb.-
utexas.edu/palmer/bio303/group23/The%20Structure%20of%20a%20-
Prion.html

The primary structural similarity between inoculated PrP sc
and host PrP is thought to be a key component of transmission
barriers between mammals. A mutation in a nucleic acid (called
a polymorphism ) in the human PrP gene (PRNP) can determine
the susceptibility to sporadic and acquired prion diseases. So
far, all patients diagnosed with vCJD have been of the PRNP
129MM genotype (a mutation in the codon 129 of the gene for
prion protein). PrP polymorphisms are known to affect the
increase in abnormal prions in mice and sheep, and the 129
genotype may play a role in human prion strain increase
(certain PrP sc types are closely associated with codon 129
genotypes).

Recently, researchers injected brain material from
BSE-infected cows and humans with vCJD and sporadic CJD
directly into the brains of two groups of mice. These mice
were genetically manipulated to have a mouse PrP genotype or a
human PrP genotype, both carrying the codon 129 mutation .
Supposedly, nearly half the population of UK has this
genotype. The mice injected with the BSE material showed the
usual symptoms and patterns of the disease. However, in mice
with the human PrP gene mutation, BSE disease showed a pattern
more consistent with sporadic CJD.

Studies of species barriers has relied on measurement of time
to onset of a clinical syndrome. Humans of a specific PrP
genotype can become infected with BSE prions, but be
asymptomatic carriers. Consequently, unexplained reports of
sporadic CJD may be caused by BSE.

so a large subpopulation of people may be sub-clincally
infected with BSE and develop the disease much later in life
or show no symptoms at all. And many cases of Alzheimer's
disease may actually be CJD.

Elzi

Bioinformatics: "What is a sheep; only millions of little bits
of sheepness whirling around and doing intricate convolutions
inside the sheep? What else is it but that?" -Flann O'Brien,
"The Third Policeman"