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From: TSS ()
Date: March 11, 2006 at 7:31 pm PST

In Reply to: U.S. Investigates Possible Mad Cow Case posted by TSS on March 11, 2006 at 2:41 pm:

3/11/2006 6:07:00 PM

Commonly Asked Questions About BSE in Products Regulated by FDA's Center for Food Safety and Applied Nutrition (CFSAN)

In light of the December 23, 2003 diagnosis of BSE in a single cow that had been imported into the United States, CFSAN has reviewed the products it regulates to ensure their safety.

What is "Mad Cow Disease" (Bovine Spongiform Encephalopathy/BSE)?

Mad Cow Disease is the commonly used name for Bovine Spongiform Encephalopathy (BSE), a slowly progressive, degenerative, fatal disease affecting the central nervous system of adult cattle. Since 1990, the U.S. Department of Agriculture (USDA) has conducted aggressive surveillance of the highest risk cattle going to slaughter in the United States. To date, the only cow that has been found to be affected with BSE was the one diagnosed with BSE in December 2003.

What causes BSE?

The exact cause of BSE is not known but it is generally accepted by the scientific community that the likely cause is infectious forms of a type of protein, prions, normally found in animals cause BSE. In cattle with BSE, these abnormal prions initially occur in the small intestines and tonsils, and are found in central nervous tissues, such as the brain and spinal cord, and other tissues of infected animals experiencing later stages of the disease.

Was a case of BSE identified in the U.S. in December 2003?

Yes, the USDA surveillance program identified the first BSE case in the U.S. in a dairy cow in Washington State. The cow was bought from a farm in Canada.

Did meat and meat products from the BSE cow enter the food supply?

As soon as the BSE case was identified, both USDA and FDA activated their BSE Emergency Response Plans, and USDA immediately recalled the meat. Meat that did enter the food supply was quickly traced and was removed from the marketplace. Moreover, all the organs in which infectious prions occur were removed at slaughter and did not enter the food supply. Consumers should feel very confident that the system of multiple firewalls maintained by Federal agencies protects them from possible exposure to BSE. In addition, we believe it is important for consumers to also understand that scientific research indicates that muscle meat is not a source of infectious prions.

Will there be additional cases?

In 1998, USDA commissioned the Harvard Center for Risk Analysis to conduct an analysis and evaluation of the U.S. regulatory measures to prevent the spread of BSE in the U.S. and to reduce the potential exposure of U.S. consumers to BSE. The Harvard study concluded that, if introduced, due to the preventive measures currently in place in the U.S., BSE is extremely unlikely to become established in the United States.

FDA and other Federal agencies have been vigilant in strengthening protective measures to reduce the U.S. consumer's risk of exposure to BSE-contaminated food and cosmetic products. Since 1989, USDA has banned imports of live ruminants, such as cattle, sheep and goats, and most products from these animals from countries known to have BSE. Subsequently, USDA expanded this ban to include both countries with BSE and countries at risk for BSE. In 1997, FDA prohibited, with some exceptions, the use of protein derived from mammalian tissues in animal feed intended for cows and other ruminants. See the FDA/CVM website at for further information on the "ruminant feed ban."

On Jan. 8, 2004, the USDA's Food Safety and Inspection Service issued new rules to enhance safeguards against BSE. Details on these rules may be found at USDA's website, Also in 2004, FDA issued a rule that prohibits the use of certain cattle material, because of the risk of BSE, in human food and cosmetics.

Does BSE affect people?

There is a disease similar to BSE called Creutzfeldt-Jacob Disease (CJD) that is found in people. A variant form of CJD (vCJD) is believed to be caused by eating contaminated beef products from BSE-affected cattle. To date, there have been 155 confirmed and probable cases of vCJD worldwide among the hundreds of thousands of people that may have consumed BSE-contaminated beef products. The one reported case of vCJD in the United States was in a young woman who contracted the disease while residing in the UK and developed symptoms after moving to the U.S.

What additional measures are being taken to ensure food safety in the U.S. from BSE?

Since 1989, the FDA and other federal agencies have had ongoing regulatory measures in place to prevent BSE contamination of U.S. food and food products. Following the identification in a Washington state dairy herd of a BSE-positive cow imported from Canada, USDA issued new regulations containing additional safeguards to further minimize risk for introduction of the BSE agent into the U.S. food supply. See USDA's website for further information..

Similarly, FDA has prohibited the use of the cattle materials that carry the highest risk of BSE in human food, including dietary supplements, and in cosmetics. FDA's rule prohibits use of the following cattle material in human food and cosmetics:

cattle material from non-ambulatory, disabled cattle,
cattle material from organs from cattle 30 months of age or older in which infectious prions are most likely to occur, and the tonsils and small intestine of cattle of all ages,
cattle material from mechanically separated (MS) (beef), and
cattle material from cattle that are not inspected and passed for human consumption

FDA's rule also requires that food and cosmetics manufacturers and processors make available to FDA any existing records relevant to their compliance with these prohibitions. FDA has also published a proposal requiring manufacturers and processors of food and cosmetics made with cattle material to establish and maintain records demonstrating that their products do not contain prohibited cattle material.

Is the food in the U.S. likely to be a BSE risk to consumers?

FDA and other federal agencies have had preventive measures in place to reduce the U.S. consumer's risk of exposure to any BSE-contaminated meat and food products. Since 1989, USDA has prohibited the importation of live animals and an imal products from BSE-positive countries. Subsequently, USDA expanded the ban to include both countries with BSE and countries at risk for BSE. Since 1997, FDA has prohibited the use of most mammalian protein in the manufacture of ruminant feed. In 2004, FDA issued a rule prohibiting the use of certain cattle materials in human food and cosmetics, and USDA issued a rule prohibiting certain cattle materials from use as human food.

Is cow's milk a source of BSE?

Scientific research indicates that BSE is not transmitted in cow's milk, even if the milk comes from a cow with BSE. Milk and milk products, even in countries with a high incidence of BSE are, therefore, considered safe.

Can milk be infected with BSE from a BSE-positive cow?

No detectable infectivity in cow's milk has been reported from any BSE-infected cows. Infectious prions have not been detected by bioassay of milk from cattle with BSE.

Does the use of bovine-derived ingredients in dietary supplements mean that they are not safe?

No. The requirements that FDA has in place should give consumers confidence that their food, including dietary supplements, is safe. Most recently, FDA published a rule that prohibits the use in human food, including dietary supplements, of the cattle materials that have the highest risk of harboring BSE infectivity. The rule applies to both imported and domestic dietary supplements and their ingredients. Furthermore, most ingredients used to produce dietary supplements and most other food ingredients come from cattle that are slaughtered when they are less than 30-months of age and, because of their age, present little risk of being BSE-positive. It is not a common occurrence for animals younger than 30 months to develop BSE.

Since the BSE-positive cow was discovered in the U.S., does that mean that dietary supplements made with domestic ingredients might be unsafe?

No. The requirements that FDA has in place should give consumers confidence that their food, including dietary supplements, is safe. Most recently, FDA published a rule that prohibits the use in human food, including dietary supplements, of the cattle materials that have the highest risk of harboring BSE infectivity. Furthermore, most ingredients used to produce dietary supplements and most other food ingredients come from cattle that are slaughtered when they are less than 30-months of age and, because of their age, present little risk of being BSE-positive.

Even though an imported BSE-positive cow was identified in the U.S., the risk to human health from dietary supplements and other foods containing cattle-derived ingredients is extremely low.

What steps is FDA currently taking to ensure the safety of dietary supplements that contain bovine ingredients?

Most recently, FDA published a rule that prohibits the use in human food, including dietary supplements, of the cattle materials that have the highest risk of harboring BSE infectivity. The rule applies to both domestic and imported dietary supplements and their ingredients. In addition, most ingredients used to produce dietary supplements and most other food ingredients come from cattle that are slaughtered when they are less than 30-months of age and, because of their age, present little risk of being BSE-positive. Further, the restrictions by USDA on the use of certain cattle and cattle tissues in human food also reduce the risks that potentially infective tissue would be used in dietary supplements. FDA also has proposed a requirement that manufacturers and processors that use cattle material in their products would be required to keep records demonstrating that these materials do not contain prohibited cattle material and that these records be made available to FDA for inspection.

Given the recent BSE case in Washington State, should consumers be concerned about cosmetics made using tallow from the rendering process?

No. The World Health Organization considers tallow to be a low risk for transmission of BSE. Specifically, the rendering process separates fats from proteins. Because the disease is transmitted by prions, which are a type of protein, they would be separated by the rendering process from the tallow or fat, which is the portion that goes into cosmetics. Additionally, the tallow is processed with excessive heat and pressure which may further minimize any risk of infectivity prior to use in cosmetics.

What about the use of gelatin, another bovine-related material, in cosmetics and dietary supplements and other foods?

FDA's rule prohibiting the use of the cattle materials that have the highest risk of harboring BSE infectivity in human food applies to gelatin. Therefore, gelatin used in human food may not be made from these cattle materials.

When and how did BSE in cattle occur?

BSE in cattle was first reported in 1986 in the United Kingdom (UK). The exact origins of BSE remain uncertain, but it is thought that cattle initially may have become infected when fed feed contaminated with scrapie-infected sheep meat-and-bone meal (MBM). Scrapie is a prion disease in sheep similar to BSE in cattle. The scientific evidence suggests that the U.K. BSE outbreak in cattle then was expanded by feeding BSE-contaminated cattle protein (MBM) to calves. The definitive nature of the BSE agent is not completely known. The agent is thought to be a modified form of a protein, called a prion, which becomes infectious and accumulates in neural tissues causing a fatal, degenerative, neurological disease. These abnormal prions are resistant to common food disinfection treatments, such as heat, to reduce or eliminate their infectivity or presence. Research is ongoing to better understand TSE diseases and the nature of prion transmission.

Is BSE in cattle the same disease as CWD in deer and elk in the U.S.?

BSE is a Transmissible Spongiform Encephalopathy (TSE), a family of similar diseases that may infect certain species of animals and people such as scrapie in sheep and goats, BSE in cattle, chronic wasting disease (CWD) in deer and elk, and variant Creutzfeldt-Jakob disease (vCJD) in people.

To date, there is no scientific evidence that BSE in cattle is related to CWD in deer and elk. FDA is working closely with other government agencies and the public health community to address CWD in wild and domesticated deer and elk herds. Wildlife and public health officials advise people not to harvest, handle, or consume any wild deer or elk that appear to be sick, regardless of the cause, especially in those states where CWD has been detected.

What countries have reported cases of BSE or are considered to have a substantial risk associated with BSE?

These countries are: Albania, Austria, Belgium, Bosnia-Herzegovina, Bulgaria, Croatia, Czech Republic, Denmark, Federal Republic of Yugoslavia, Finland, France, Germany, Greece, Hungary, Ireland, Israel, Italy, Liechtenstein, Luxembourg, former Yugoslavia Republic of Macedonia, The Netherlands, Norway, Oman, Poland, Portugal, Romania, Slovak Republic, Slovenia, Spain, Sweden, Switzerland, Japan, and United Kingdom (Great Britain including Northern Ireland and the Falkland Islands).

Canada (May 2003) and the U.S. (December 2003) each have recently reported one BSE-positive cow but remain countries considered to have a low risk. The U.S. BSE-positive cow reported in December 2003 was confirmed to have been imported from Canada in 2001.

3/11/2006 6:11:00 PM

KLA Cattle Update: USDA Announces Inconclusive BSE Test Results

Late Friday, officials with USDA’s Animal and Plant Health Inspection Service received inconclusive rapid test results from an animal sampled as part of the ongoing enhanced BSE surveillance program. The animal did not enter the food or feed supply.

USDA is conducting confirmatory tests at the National Veterinary Services Laboratory in Ames, Iowa, using both the immunohistochemistry analysis and Western blot testing methods. USDA expects the additional tests to be completed in four to seven days.

"This inconclusive result does not mean we have found a new case of BSE. Inconclusive results are a normal component of most screening tests, which are designed to be extremely sensitive so they will detect any sample that could possibly be positive,” said Chief Veterinary Medical Officer John Clifford, in a statement Saturday.

The BSE agent is not found in whole muscle cuts of beef, such as steaks and roasts, or ground beef. Any tissues considered at risk for carrying the BSE agent are removed at the processing plant and excluded from the food or feed supply.

Even if inconclusive tests are confirmed as BSE, scientists, government experts and food industry leaders agree U.S. beef will remain very safe due to the firewalls in place to protect consumers and the nation’s cattle herd.

NCBA and KLA will continue to monitor the situation throughout the weekend.

> In 1998, USDA commissioned the Harvard Center for Risk Analysis to conduct an analysis and evaluation of the U.S. regulatory measures to

> prevent the spread of BSE in the U.S. and to reduce the potential exposure of U.S. consumers to BSE. The Harvard study concluded that, if

> introduced, due to the preventive measures currently in place in the U.S., BSE is extremely unlikely to become established in the United States.

THIS is the first rubber-stamp that is whooped out. but it's just more BSe.

SEE for yourself, and then ask yourself why they don't quote this ;

SUPPRESSED peer review of Harvard study October 31, 2002

> Late Friday, officials with USDA’s Animal and Plant Health Inspection Service received

> inconclusive rapid test results from an animal sampled as part of the ongoing enhanced BSE

> surveillance program. The animal did not enter the food or feed supply.

THIS quote is another rubber stamp they have ;-) this is for marketing purposes i.e. give the market time to digest.

FUNNY or another coincidence how most of these inconclusives come out on Friday ;-)

2. Packers and Stockyards Programs: Continuing Problems with GIPSA Investigations of Competitive Practices, by Daniel Bertoni, acting director, natural resources and environment, before the Senate Committee on Agriculture, Nutrition, and Forestry. GAO-06-532T, March 9.

OIG has been very busy thank God.

NOW, how long it takes them will be up to what type testing protocols the USDA et al decides to use, and if

they send the sample to Weybridge like the original BSE response plan called for, before GW et al traded there

soul and ours for the BSE MRR policy, GWs answer to mad cow disease i.e. the legal trading of all strains

of TSE aka mad cow diseases. the original BSE response plan also called for the tissue sample to be hand carried

to Weybridge and a 24 to 96 hour turnaround on confirmation if i am not mistaken. nope, if this baby comes back

negative and they don't send the sample to Weybridge for additional confirmation, then the Honorable Phyllis Fong

and the OIG will have to get there paddle out again.

past history shows they used the lease likely to detect BSE/TSE, even after one of ther top prion gods told them so in 2003.

maybe that is why she was put out to pasture with a few others. but old ronald mcdonald and the big mac knew what they were doing;

NOW, let us look at another BSE ROUNDTABLE DISCUSSION by USDA et al in the year 2003, please note the BSE science on IHC testing then, and then compare to now, and then ponder those other 9,200 cattle of the infamous June 2004 BSE cover-up program, that did not have rapid testing or WB, just IHC, the lease likely to find BSE/TSE ;

USDA 2003

We have to be careful that we don't get so set in the way we do things that
we forget to look for different emerging variations of disease. We've gotten
away from collecting the whole brain in our systems. We're using the brain
stem and we're looking in only one area. In Norway, they were doing a
project and looking at cases of Scrapie, and they found this where they did
not find lesions or PRP in the area of the obex. They found it in the
cerebellum and the cerebrum. It's a good lesson for us. Ames had to go
back and change the procedure for looking at Scrapie samples. In the USDA,
we had routinely looked at all the sections of the brain, and then we got
away from it. They've recently gone back.
Dr. Keller: Tissues are routinely tested, based on which tissue provides an
'official' test result as recognized by APHIS

Dr. Detwiler: That's on the slaughter. But on the clinical cases, aren't
they still asking for the brain? But even on the slaughter, they're looking
only at the brainstem. We may be missing certain things if we confine
ourselves to one area.


Dr. Detwiler: It seems a good idea, but I'm not aware of it.
Another important thing to get across to the public is that the negatives
do not guarantee absence of infectivity. The animal could be early in the
disease and the incubation period. Even sample collection is so important.
If you're not collecting the right area of the brain in sheep, or if
collecting lymphoreticular tissue, and you don't get a good biopsy, you
could miss the area with the PRP in it and come up with a negative test.
There's a new, unusual form of Scrapie that's been detected in Norway. We
have to be careful that we don't get so set in the way we do things that we
forget to look for different emerging variations of disease. We've gotten
away from collecting the whole brain in our systems. We're using the brain
stem and we're looking in only one area. In Norway, they were doing a
project and looking at cases of Scrapie, and they found this where they did
not find lesions or PRP in the area of the obex. They found it in the
cerebellum and the cerebrum. It's a good lesson for us. Ames had to go
back and change the procedure for looking at Scrapie samples. In the USDA,
we had routinely looked at all the sections of the brain, and then we got
away from it. They've recently gone back.

Dr. Keller: Tissues are routinely tested, based on which tissue provides an
'official' test result as recognized by APHIS

Dr. Detwiler: That's on the slaughter. But on the clinical cases, aren't
they still asking for the brain? But even on the slaughter, they're looking
only at the brainstem. We may be missing certain things if we confine
ourselves to one area.



Completely Edited Version

Accomplished this day, Wednesday, December 11, 2003, Denver, Colorado


National Veterinary Services Laboratory (NVSL) Immunohistochemistry (IHC) Testing Summary

The BSE enhanced surveillance program involves the use of a rapid screening test, followed by confirmatory testing for any samples that come back "inconclusive." The weekly summary below captures all rapid tests conducted as part of the enhanced surveillance effort. It should be noted that since the enhanced surveillance program began, USDA has also conducted approximately 9,200 routine IHC tests on samples that did not first undergo rapid testing.


James J. Kramer, Ph.D.
Vice President, Corporate Operations

Dick Crawford

Corporate Vice President, Government Relations

630-623-6754 Direct

630-623-3057 Facsimile

Docket No. 03-025IFA] FSIS Prohibition of the Use of Specified Risk Materials for Human Food and Requirement for the Disposition of Non-Ambulatory Disabled Cattle


Docket No. 2002N-0273 C-534 VOL 45 (PhRMA) and Entered On February 17, 2006
Date: March 10, 2006 at 5:23 pm PST

Marie A. Vodicka, PhD

Assistant Vice President

Biologics & Blotechnology

Scientlflc & Regulatory Affairs


Division of Dockets Management (HFA-305)

Linda Detwiler, DVM

Consultant, TSE Risk Management

Robert G. Rohwer, Ph.D.

Director, Molecular Neurovirology Laboratory

Veterans Affairs Medical Center

Medical Research Service 151

Docket Management Docket: 02N-0273 - Substances Prohibited From Use in

Animal Food or Feed; Animal Proteins Prohibited in Ruminant Feed

Comment Number: EC -10

Accepted - Volume 2


Docket No, 04-047-l Regulatory Identification No. (RIN) 091O-AF46 NEW BSE SAFEGUARDS (comment submission)


Docket No. 2003N-0312 Animal Feed Safety System [TSS SUBMISSION]

Asante/Collinge et al, that BSE transmission to the 129-methionine

genotype can lead to an alternate phenotype that is indistinguishable

from type 2 PrPSc, the commonest _sporadic_ CJD;

Page 1. J Freas, William From: Sent: To: Subject: Terry S. Singeltary

Sr. [] Monday, January 08,200l 3:03 PM freas ...

EFSA Scientific Report on the Assessment of the Geographical BSE-Risk (GBR) of the United States of America (USA)
Last updated: 19 July 2005
Adopted July 2004 (Question N° EFSA-Q-2003-083)

Summary of the Scientific Report

The European Food Safety Authority and its Scientific Expert Working Group on the Assessment of the Geographical Bovine Spongiform Encephalopathy (BSE) Risk (GBR) were asked by the European Commission (EC) to provide an up-to-date scientific report on the GBR in the United States of America, i.e. the likelihood of the presence of one or more cattle being infected with BSE, pre-clinically as well as clinically, in USA. This scientific report addresses the GBR of USA as assessed in 2004 based on data covering the period 1980-2003.

The BSE agent was probably imported into USA and could have reached domestic cattle in the middle of the eighties. These cattle imported in the mid eighties could have been rendered in the late eighties and therefore led to an internal challenge in the early nineties. It is possible that imported meat and bone meal (MBM) into the USA reached domestic cattle and leads to an internal challenge in the early nineties.

A processing risk developed in the late 80s/early 90s when cattle imports from BSE risk countries were slaughtered or died and were processed (partly) into feed, together with some imports of MBM. This risk continued to exist, and grew significantly in the mid 90’s when domestic cattle, infected by imported MBM, reached processing. Given the low stability of the system, the risk increased over the years with continued imports of cattle and MBM from BSE risk countries.

EFSA concludes that the current GBR level of USA is III, i.e. it is likely but not confirmed that domestic cattle are (clinically or pre-clinically) infected with the BSE-agent. As long as there are no significant changes in rendering or feeding, the stability remains extremely/very unstable. Thus, the probability of cattle to be (pre-clinically or clinically) infected with the BSE-agent persistently increases.

Publication date: 20 August 2004

Docket: 02N-0276 - Bioterrorism Preparedness; Registration of Food Facilities, Section 305
Comment Number: EC-254 [TSS SUBMISSION]


Greetings list members,

i just cannot accept this;

> 23 kg of meat in a suitcase (suitcase bomb...TSS)

> The data do not provide a species of origin code for these

> products, therefore they may not contain any ruminant product. what kind of statement is this?

how stupid do they think we are? it could also very well mean that _all_ of it was ruminant based products !


Greetings FDA and public, if you go to the below site, and search all BSE known countries and check out their air traffic illegal meat they have confiscated, and check out the low number checked, compared to actual passenger traffic, would not take too much for some nut to bring in FMD/TSEs into the USA as a 'suitcase bomb'.

[[Under APHIS-PPQ's agricultural quarantine inspection monitoring, 284 air passengers from Israel were sampled for items of agricultural interest in fiscal year 2001. Seven of these passengers, or 2 percent, carried a total of 11 kg of meat items that could potentially harbor the pathogen that causes BSE. None of these passengers from whom meat items were confiscated reported plans to visit or work on a ranch or farm during their visit to the U.S.]]

if they were to have questioned the terrorist that bombed the Twin Towers with jets, if they were to have questioned them at flight school in the USA, i am sure that they would have said they did not intend to visit the Twin Towers as a flying bomb either. what am i thinking, they probably did ask this? stupid me.

[[In 1999 a small amount of non-species specific meat and offal was imported and a small amount of fetal bovine serum (FBS) was also imported. FBS is considered to have a relatively low risk of transmitting BSE.]]

more of the USA infamous 'non-species coding system', wonder how many of these species are capable of carrying a TSE?


Greetings again List Members, let me kick a madcow around here a bit. on the imports from Poland and the infamous USA 'non-species' coding system. the USDA/APHIS states;

> During the past four years (1998 - 2001), US imports from

> Poland included non-species specific animal products

> used in animal feeds and non-species specific sausage and offal

> products (Table 3). Given US restrictions on ruminant product

> imports, these US imports should not have contained ruminant

> material.

NOW, if you read Polands GBR risk assessment and opinion on BSE, especially _cross-contamination_, it states;

ANNEX 1 Poland - Summary of the GBR-Assessment, February 2001 EXTERNAL CHALLENGE STABILITY INTERACTION OF EXTERNAL CHALLENGE AND STABILITY The very high to extremely high external challenge met a very unstable system and could have led to contamination of domestic cattle in Poland from 1987 onwards. This internal challenge again met the still very unstable system and increased over time. The continuing very high external challenge supported this development. Not OK MBM-ban since 1997, but no feed controls. Reasonably OK Heat treatment equivalent to 133°C / 20min / 3 bar standards, but no evidence provided on compliance. Not OK. No SRM-ban, SRM are rendered and included in cattle feed. BSE surveillance: Not sufficient before 2001. Cross-contamination: Lines for ruminant and non-ruminant feed in feed-mills only separated in time and no analytical controls carried out. Likely present since 1987 and growing. see full text and ANNEX 1 at;

so in my humble opinion, the statement by the USDA/APHIS that ''these US imports _should_ not have contained ruminant materials, is a joke. a sad joke indeed. * POLAND BSE GBR RISK ASSESSMENT


full text;


Subject: Poland Bse and animal nutrition & bse, scrapie testing Member States
Date: February 8, 2006 at 10:58 am PST

01/2006 Poland Bse and animal nutrition 7693-2005


Subject: New case of mad cow disease in Poland
Date: December 28, 2005 at 10:20 am PST

AFX News Limited
New case of mad cow disease in Poland
12.28.2005, 02:36 AM


##################### Bovine Spongiform Encephalopathy #####################

Subject: Creutzfeldt Jakob disease statistics Monday 6 March 2006 Reference number: 2006/0088
Date: March 6, 2006 at 3:22 pm PST

Monthly Creutzfeldt Jakob disease statistics
Monday 6 March 2006
Reference number:

The Department of Health is today issuing the latest information about the numbers of known cases of Creutzfeldt Jakob disease. This includes cases of variant Creutzfeldt Jakob disease (vCJD) - the form of the disease thought to be linked to BSE. The position is as follows:

Definite and probable CJD cases in the UK:

As at 3 March 2006

Summary of vCJD cases


Deaths from definite vCJD (confirmed): 110

Deaths from probable vCJD (without neuropathological confirmation): 44

Deaths from probable vCJD (neuropathological confirmation pending): 0

Number of deaths from definite or probable vCJD (as above): 154


Number of probable vCJD cases still alive: 6

Total number of definite or probable vCJD (dead and alive): 160

The next table will be published on Monday 3rd April 2006

Referrals: a simple count of all the cases which have been referred to the National CJD Surveillance Unit for further investigation in the year in question. CJD may be no more than suspected; about half the cases referred in the past have turned out not to be CJD. Cases are notified to the Unit from a variety of sources including neurologists, neuropathologists, neurophysiologists, general physicians, psychiatrists, electroencephalogram (EEG) departments etc. As a safety net, death certificates coded under the specific rubrics 046.1 and 331.9 in the 9th ICD Revisions are obtained from the Office for National Statistics in England and Wales, the General Register Office for Scotland and the General Register Office for Northern Ireland.

Deaths: All columns show the number of deaths that have occurred in definite and probable cases of all types of CJD and GSS in the year shown. The figures include both cases referred to the Unit for investigation while the patient was still alive and those where CJD was only discovered post mortem (including a few cases picked up by the Unit from death certificates). There is therefore no read across from these columns to the referrals column. The figures will be subject to retrospective adjustment as diagnoses are confirmed.

Definite cases: this refers to the diagnostic status of cases. In definite cases the diagnosis will have been pathologically confirmed, in most cases by post mortem examination of brain tissue (rarely it may be possible to establish a definite diagnosis by brain biopsy while the patient is still alive).

Probable vCJD cases: are those who fulfil the ‘probable’ criteria set out in the Annex and are either still alive, or have died and await post mortem pathological confirmation. Those still alive will always be shown within the current year's figures.

Sporadic: Classic CJD cases with typical EEG and brain pathology. Sporadic cases appear to occur spontaneously with no identifiable cause and account for 85% of all cases.

Probable sporadic: Cases with a history of rapidly progressive dementia, typical EEG and at least two of the following clinical features; myoclonus, visual or cerebellar signs, pyramidal/extrapyramidalsigns or akinetic mutism.

Iatrogenic: where infection with classic CJD has occurred accidentally as the result of a medical procedure. All UK cases have resulted from treatment with human derived pituitary growth hormones or from grafts using dura mater (a membrane lining the skull).

Familial: cases occurring in families associated with mutations in the PrP gene (10 - 15% of cases).

GSS: Gerstmann-Straussler-Scheinker syndrome - an exceedingly rare inherited autosomal dominant disease, typified by chronic progressive ataxia and terminal dementia. The clinical duration is from 2 to 10 years, much longer than for CJD.

vCJD: Variant CJD, the hitherto unrecognised variant of CJD discovered by the National CJD Surveillance Unit and reported in The Lancet on 6 April 1996. This is characterised clinically by a progressive neuropsychiatric disorder leading to ataxia, dementia and myoclonus (or chorea) without the typical EEG appearance of CJD. Neuropathology shows marked spongiform change and extensive florid plaques throughout the brain.

Definite vCJD cases still alive: These will be cases where the diagnosis has been pathologically confirmed (by brain biopsy).

Related links
Download CJD statistics March 2006 (PDF, 12K)
Notes to editor















PROBABLE: I and 4/5 OF II and III A and III B or I and IV A

* depression, anxiety, apathy, withdrawal, delusions.

** this includes both frank pain and/ or unpleasant dysaesthesia

*** generalised triphasic periodic complexes at approximately one per second

****spongiform change and extensive PrP deposition with florid plaques, throughout the cerebrum and cerebellum.

Reference number:

ALL CJD * As at 3rd March 2006 (see increase in sCJD)


notice steady increase, but also notice in 2005, # 7 the 38 pendings cases through Oct. and #8 includes 53 type pending, 1 type unknown.

if you look at 2003 there were 3 type unknown.

wonder if they were the same or different than the unknown in 2005?

considering the soup that has been brewing over here in the USA for years via the rendering of BSE and atypical TSE in cattle, CWD, Scrapie, a few TME cases (not too much due to scent gland, but there were a few rendered, but all this, and you have one hell of a recipe for a new strains of TSE in humans. then who knows what 'friendly fire' cases would look like from this soup via secondary transmission via medical/surgical/dental arena. ...TSS

National Prion Disease Pathology Surveillance Center case exams...

HUMAN and ANIMAL TSE Classifications i.e. mad cow
disease and the UKBSEnvCJD only theory

TSEs have been rampant in the USA for decades in many
species, and they all have been rendered and fed back
to animals for human/animal consumption. I propose that
the current diagnostic criteria for human TSEs only
enhances and helps the spreading of human TSE from the
continued belief of the UKBSEnvCJD only theory in 2005.
With all the science to date refuting it, to continue
to validate this myth, will only spread this TSE agent
through a multitude of potential routes and sources
i.e. consumption, surgical, blood, medical, cosmetics
etc. I propose as with Aguzzi, Asante, Collinge,
Caughey, Deslys, Dormont, Gibbs, Ironside, Manuelidis,
Marsh, et al and many more, that the world of TSE
Tranmissible Spongiform Encephalopathy is far from an
exact science, but there is enough proven science to
date that this myth should be put to rest once and for
all, and that we move forward with a new classification
for human and animal TSE that would properly identify
the infected species, the source species, and then the
route. This would further have to be broken down to
strain of species and then the route of transmission
would further have to be broken down. Accumulation and
Transmission are key to the threshold from subclinical
to clinical disease, and of that, I even believe that
physical and or blunt trauma may play a role of onset
of clinical symptoms in some cases, but key to all
this, is to stop the amplification and transmission of
this agent, the spreading of, no matter what strain.
BUT, to continue with this myth that the U.K. strain of
BSE one strain in cows, and the nv/v CJD, one strain in
humans, and that all the rest of human TSE is one
single strain i.e. sporadic CJD (when to date there are
6 different phenotypes of sCJD), and that no other
animal TSE transmits to humans, to continue with this
masquerade will only continue to spread, expose, and
kill, who knows how many more in the years and decades
to come. ONE was enough for me, My Mom, hvCJD, DOD
12/14/97 confirmed, which is nothing more than another
mans name added to CJD, like CJD itself, Jakob and
Creutzfeldt, or Gerstmann-Straussler-Scheinker
syndrome, just another CJD or human TSE, named after
another human. WE are only kidding ourselves with the
current diagnostic criteria for human and animal TSE,
especially differentiating between the nvCJD vs the
sporadic CJD strains and then the GSS strains and also
the FFI fatal familial insomnia strains or the ones
that mimics one or the other of those TSE? Tissue
infectivity and strain typing of the many variants of
the human and animal TSEs are paramount in all variants
of all TSE. There must be a proper classification that
will differentiate between all these human TSE in order
to do this. With the CDI and other more sensitive
testing coming about, I only hope that my proposal will
some day be taken seriously.

My name is Terry S. Singeltary Sr. and I am no
scientist, no doctor and have no PhDs, but have been
independently researching human and animal TSEs since
the death of my Mother to the Heidenhain Variant of
Creutzfeldt Jakob Disease on December 14, 1997
'confirmed'. ...TSS

Terry S. Singeltary Sr.
P.O. Box 42
Bacliff, Texas USA 77518


Full Text
Diagnosis and Reporting of Creutzfeldt-Jakob Disease
Singeltary, Sr et al.
JAMA.2001; 285: 733-734

Coexistence of multiple PrPSc types in individuals with

Creutzfeldt-Jakob disease

Magdalini Polymenidou, Katharina Stoeck, Markus
Glatzel, Martin Vey, Anne Bellon, and Adriano Aguzzi


Background The molecular typing of sporadic
Creutzfeldt-Jakob disease (CJD) is based on the size
and glycoform

ratio of protease-resistant prion protein (PrPSc), and
on PRNP haplotype. On digestion with proteinase K, type
1 and

type 2 PrPSc display unglycosylated core fragments of
21 kDa and 19 kDa, resulting from cleavage around amino

acids 82 and 97, respectively.

Methods We generated anti-PrP monoclonal antibodies to
epitopes immediately preceding the differential proteinase

K cleavage sites. These antibodies, which were
designated POM2 and POM12, recognise type 1, but not
type 2, PrPSc.

Findings We studied 114 brain samples from 70 patients
with sporadic CJD and three patients with variant CJD.

Every patient classified as CJD type 2, and all variant
CJD patients, showed POM2/POM12 reactivity in the

cerebellum and other PrPSc-rich brain areas, with a
typical PrPSc type 1 migration pattern.

Interpretation The regular coexistence of multiple
PrPSc types in patients with CJD casts doubts on the
validity of

electrophoretic PrPSc mobilities as surrogates for
prion strains, and questions the rational basis of
current CJD



The above results set the existing CJD classifications

into debate and introduce interesting questions about

human CJD types. For example, do human prion types

exist in a dynamic equilibrium in the brains of affected

individuals? Do they coexist in most or even all CJD

cases? Is the biochemically identified PrPSc type simply

the dominant type, and not the only PrPSc species?

Published online October 31, 2005

Detection of Type 1 Prion Protein in Variant

Creutzfeldt-Jakob Disease

Helen M. Yull,* Diane L. Ritchie,*

Jan P.M. Langeveld,? Fred G. van Zijderveld,?

Moira E. Bruce,? James W. Ironside,* and

Mark W. Head*

From the National CJD Surveillance Unit,* School of

and Clinical Medicine, University of Edinburgh, Edinburgh,

United Kingdom; Central Institute for Animal Disease

(CIDC)-Lelystad, ? Lelystad, The Netherlands; Institute
for Animal

Health, Neuropathogenesis Unit, ? Edinburgh, United Kingdom

Molecular typing of the abnormal form of the prion

protein (PrPSc) has come to be regarded as a powerful

tool in the investigation of the prion diseases. All

thus far presented indicates a single PrPSc molecular

type in variant Creutzfeldt-Jakob disease (termed

type 2B), presumably resulting from infection with a

single strain of the agent (bovine spongiform

Here we show for the first time that the PrPSc

that accumulates in the brain in variant Creutzfeldt-

Jakob disease also contains a minority type 1 component.

This minority type 1 PrPSc was found in all 21

cases of variant Creutzfeldt-Jakob disease tested,

of brain region examined, and was also

present in the variant Creutzfeldt-Jakob disease tonsil.

The quantitative balance between PrPSc types was maintained

when variant Creutzfeldt-Jakob disease was

transmitted to wild-type mice and was also found in

bovine spongiform encephalopathy cattle brain, indicating

that the agent rather than the host specifies their

relative representation. These results indicate that PrPSc

molecular typing is based on quantitative rather than

qualitative phenomena and point to a complex relationship

between prion protein biochemistry, disease phenotype

and agent strain. (Am J Pathol 2006, 168:151-157;

DOI: 10.2353/ajpath.2006.050766)



In the apparent absence of a foreign nucleic acid genome

associated with the agents responsible for transmissible

spongiform encephalopathies or prion diseases,

efforts to provide a molecular definition of agent strain

have focused on biochemical differences in the abnormal,

disease-associated form of the prion protein, termed

PrPSc. Differences in PrPSc conformation and glycosylation

have been proposed to underlie disease phenotype

and form the biochemical basis of agent strain. This

proposal has found support in the observation that the

major phenotypic subtypes of sCJD appear to correlate

with the presence of either type 1 or type 2 PrPSc in

combination with the presence of either methionine or

valine at codon 129 of the prion protein gene.2 Similarly,

the PrPSc type associated with vCJD correlates with the

presence of type 2 PrPSc and is distinct from that found in

sCJD because of a characteristically high occupancy of

both N-linked glycosylation sites (type 2B).6,11 The

means by which such conformational difference is detected

is somewhat indirect; relying on the action of proteases,

primarily proteinase K, to degrade the normal

Figure 6. Type 1 PrPSc is a stable minority component
of PrPSc from the vCJD

brain. Western blot analysis of PrP in a sample of
cerebral cortex from a

of vCJD during digestion with proteinase K is shown.
Time points assayed

are indicated in minutes (T0, 5, 10, 30, 60, 120, 180).
Duplicate blots were

probed with 3F4, which detects both type 1 and type 2
PrPSc, and with 12B2,

which detects type 1. The insert shows a shorter
exposure of the same time

course study from a separate experiment also probed
with 3F4. Both blots

included samples of cerebral cortex from a case of
sporadic CJD MM1 (Type

1) and molecular weight markers (Markers) indicate
weights in kd.

Figure 7. A minority type 1-like PrPSc is found in vCJD
tonsil, vCJD

to mice and in BSE. Western blot analysis of PrPSc in a

sample of tonsil from a case of vCJD (Tonsil), in a
concentrated brain

of a wild-type mouse (C57BL) infected with vCJD and in
a sample of cattle

BSE brain (BSE) is shown. Tissue extracts were digested
with proteinase K.

Duplicate blots were probed with either 3F4 or 6H4,
both of which detect

type 1 and type 2 PrPSc, and with 12B2, which detects
type 1. The blots

included samples of cerebral cortex from a case of
sporadic CJD MM1 (Type

1) and molecular weight markers (Markers) indicate
weights in kd.

Type 1 PrPSc in Variant Creutzfeldt-Jakob Disease 155

AJP January 2006, Vol. 168, No. 1

cellular form of PrP and produce a protease-resistant

core fragment of PrPSc that differs in the extent of its

N-terminal truncation according to the original


A complication has recently arisen with the finding that

both type 1 and type 2 can co-exist in the brains of

patients with sCJD.2,5-8 More recently this same phenomenon

has been demonstrated in patients with iatrogenically

acquired and familial forms of human prion disease.

9,10 The existence of this phenomenon is now

beyond doubt but its prevalence and its biological

remain a matter of debate.

Conventional Western blot analysis using antibodies

that detect type 1 and type 2 PrPSc has severe quantitative

limitations for the co-detection of type 1 and type 2

PrPSc in individual samples, suggesting that the prevalence

of co-occurrence of the two types might be underestimated.

We have sought to circumvent this problem by

using an antibody that is type 1-specific and applied this

to the sole remaining human prion disease where the

phenomenon of mixed PrPSc types has not yet been

shown, namely vCJD.

These results show that even in vCJD where susceptible

individuals have been infected supposedly by a

single strain of agent, both PrPSc types co-exist: a

reminiscent of that seen when similarly discriminant

antibodies were used to analyze experimental BSE in

sheep.14,17 In sporadic and familial CJD, individual

brains can show a wide range of relative amounts of the

two types in samples from different regions, but where

brains have been thoroughly investigated a predominant

type is usually evident.2,6,10 This differs from this

on vCJD, where type 1 is present in all samples

but always as a minor component that never

reaches a level at which it is detectable without a type

1-specific antibody. It would appear that the relative

between type 1 and type 2 is controlled within

certain limits in the vCJD brain. A minority type-1-like

band is also detected by 12B2 in vCJD tonsil, in BSE

brain and in the brains of mice experimentally infected

with vCJD, suggesting that this balance of types is agent,

rather than host or tissue, specific. Interestingly the

signature" of the type 2 PrPSc found in vCJD (type

2B) is also seen in the type 1 PrPSc components, suggesting

that it could legitimately be termed type 1B.

PrPSc isotype analysis has proven to be extremely

useful in the differential diagnosis of CJD and is
likely to

continue to have a major role in the investigation of human

prion diseases. However, it is clear, on the basis of

these findings, that molecular typing has quantitative

and that any mechanistic explanation of prion

replication and the molecular basis of agent strain

must accommodate the co-existence of multiple

prion protein conformers. Whether or not the different

conformers we describe here correlate in a simple and

direct way with agent strain remains to be determined. In

principle two interpretations present themselves: either

the two conformers can be produced by a single strain of

agent or vCJD (and, therefore, presumably BSE) results

from a mixture of strains, one of which generally

Evidence for the isolation in mice of more than one

strain from individual isolates of BSE has been presented


One practical consequence of our findings is that the

correct interpretation of transmission studies will depend

on a full examination of the balance of molecular types

present in the inoculum used to transmit disease, in

to a thorough analysis of the molecular types that

arise in the recipients. Another consequence relates to

the diagnostic certainty of relying on PrPSc molecular

type alone when considering the possibility of BSE

or secondary transmission in humans who have a

genotype other than methionine at codon 129 of the

PRNP gene. In this context it is interesting to note
that this

minority type 1B component resembles the type 5 PrPSc

described previously to characterize vCJD transmission

into certain humanized PRNP129VV transgenic mouse

models.12,20 This apparently abrupt change in molecular

phenotype might represent a selection process imposed

by this particular transgenic mouse model. Irrespective of

whether this proves to be the case, the results shown

here point to further complexities in the relationship

the physico-chemical properties of the prion protein,

human disease phenotype, and prion agent strain.



Type 1 PrPSc in Variant Creutzfeldt-Jakob Disease 157

AJP January 2006, Vol. 168, No. 1 ...TSS

Neuropathology and Applied Neurobiology



, 565-579 doi: 10.1111/j.1365-2990.2005.00697.x

© 2005 Blackwell Publishing Ltd


Blackwell Science, LtdOxford, UKNANNeuropathology and
Applied Neurobiology0305-1846Blackwell Publishing Ltd, 2005


Review article

Phenotypic variability in human prion diseases

J. W. Ironside, D. L. Ritchie and M. W. Head

National Creutzfeldt-Jakob Disease Surveillance Unit,
Division of Pathology, University of Edinburgh,
Edinburgh, UK

J. W. Ironside, D. L. Ritchie and M. W. Head (2005)

Neuropathology and Applied Neurobiology



Phenotypic variability in human prion diseases

Human prion diseases are rare neurodegenerative disorders

that can occur as sporadic, familial or acquired disorders.

Within each of these categories there is a wide range

of phenotypic variation that is not encountered in other

neurodegenerative disorders. The identification of the

prion protein and its key role in the pathogenesis of this

diverse group of diseases has allowed a fuller

of factors that influence disease phenotype. In particular,

the naturally occurring polymorphism at codon 129

in the prion protein gene has a major influence on the

phenotype in sporadic, familial and acquired prion

diseases, although the underlying mechanisms remain

unclear. Recent technical advances have improved our

ability to study the isoforms of the abnormal prion protein

in the brain and in other tissues. This has lead to the

of molecular strain typing, in which different isoforms

of the prion protein are proposed to correspond to

individual strains of the transmissible agent, each with

specific biological properties. In sporadic

disease there are at least six major combinations of codon

129 genotype and prion protein isotype, which appear to

relate to distinctive clinical subgroups of this disease.

However, these relationships are proving to be more complex

than first considered, particularly in cases with more

than a single prion protein isotype in the brain. Further

work is required to clarify these relationships and to

explain the mechanism of neuropathological targeting of

specific brain regions, which accounts for the diversity of

clinical features within human prion diseases.

© 2005 Blackwell Publishing Ltd, Neuropathology and
Applied Neurobiology, 31, 565-579

BSE prions propagate as either variant CJD-like or

sporadic CJD-like prion strains in transgenic mice

expressing human prion protein

The EMBO Journal Vol. 21 No. 23 pp. 6358±6366, 2002

Emmanuel A.Asante, Jacqueline M.Linehan,

Melanie Desbruslais, Susan Joiner,

Ian Gowland, Andrew L.Wood, Julie Welch,

Andrew F.Hill, Sarah E.Lloyd,

Jonathan D.F.Wadsworth and

John Collinge1

MRC Prion Unit and Department of Neurodegenerative Disease,

Institute of Neurology, University College, Queen Square,

London WC1N 3BG, UK

1Corresponding author


Variant Creutzfeldt±Jakob disease (vCJD) has been

recognized to date only in individuals homozygous for

methionine at PRNP codon 129. Here we show that

transgenic mice expressing human PrP methionine

129, inoculated with either bovine spongiform

encephalopathy (BSE) or variant CJD prions, may

develop the neuropathological and molecular phenotype

of vCJD, consistent with these diseases being

caused by the same prion strain. Surprisingly, however,

BSE transmission to these transgenic mice, in

addition to producing a vCJD-like phenotype, can also

result in a distinct molecular phenotype that is

from that of sporadic CJD with PrPSc

type 2. These data suggest that more than one BSEderived

prion strain might infect humans; it is therefore

possible that some patients with a phenotype consistent

with sporadic CJD may have a disease arising

from BSE exposure.


These studies further strengthen the evidence that vCJD

is caused by a BSE-like prion strain. Also, remarkably, the

key neuropathological hallmark of vCJD, the presence of

abundant ¯orid PrP plaques, can be recapitulated on BSE

or vCJD transmission to these mice. However, the most

surprising aspect of the studies was the ®nding that an

alternate pattern of disease can be induced in 129MM

Tg35 mice from primary transmission of BSE, with a

molecular phenotype indistinguishable from that of a

of sporadic CJD. This ®nding has important potential

implications as it raises the possibility that some humans

infected with BSE prions may develop a clinical disease

indistinguishable from classical CJD associated with type 2

PrPSc. This is, in our experience, the commonest molecular

sub-type of sporadic CJD. In this regard, it is of interest

that the reported incidence of sporadic CJD has risen
in the

UK since the 1970s (Cousens et al., 1997). This has been

attributed to improved case ascertainment, particularly as

much of the rise is reported from elderly patients and

similar rises in incidence were noted in other European

countries without reported BSE (Will et al., 1998).

However, it is now clear that BSE is present in many

European countries, albeit at a much lower incidence than

was seen in the UK. While improved ascertainment is

likely to be a major factor in this rise, that some of

additional cases may be related to BSE exposure cannot be

ruled out. It is of interest in this regard that a 2-fold

increase in the reported incidence of sporadic CJD in 2001

has recently been reported for Switzerland, a country that

had the highest incidence of cattle BSE in continental

Europe between 1990 and 2002 (Glatzel et al., 2002). No

epidemiological case±control studies with strati®cation of

CJD cases by molecular sub-type have yet been reported.

It will be important to review the incidence of sporadic

CJD associated with PrPSc type 2 and other molecular

in both BSE-affected and unaffected countries in the

light of these ®ndings. If human BSE prion infection can

result in propagation of type 2 PrPSc, it would be expected

that such cases would be indistinguishable on clinical,

pathological and molecular criteria from classical CJD. It

may also be expected that such prions would behave

biologically like those isolated from humans with sporadic

CJD with type 2 PrPSc. The transmission properties of

prions associated with type 2 PrPSc from BSE-inoculated

129MM Tg35 mice are being investigated by serial


We consider these data inconsistent with contamination

of some of the 129MM Tg35 mice with sporadic CJD

prions. These transmission studies were performed according

to rigorous biosafety protocols for preparation of

inocula and both the inoculation and care of mice, which

are all uniquely identi®ed by sub-cutaneous transponders.

However, crucially, the same BSE inocula have been used

on 129VV Tg152 and 129MM Tg45 mice, which are

highly sensitive to sporadic CJD but in which such

transmissions producing type 2 PrPSc were not observed.

Furthermore, in an independent experiment, separate

inbred lines of wild-type mice, which are highly resistant

to sporadic CJD prions, also propagated two distinctive

PrPSc types on challenge with either BSE or vCJD. No

evidence of spontaneous prion disease or PrPSc has been

seen in groups of uninoculated or mock-inoculated aged

129MM Tg35 mice.

While distinctive prion isolates have been derived from

BSE passage in mice previously (designated 301C and

301V), these, in contrast to the data presented here, are

propagated in mice expressing different prion proteins

(Bruce et al., 1994). It is unclear whether our ®ndings

indicate the existence of more than one prion strain in

individual cattle with BSE, with selection and preferential

replication of distinct strains by different hosts, or that

`mutation' of a unitary BSE strain occurs in some types of

host. Western blot analysis of single BSE isolates has not

shown evidence of the presence of a proportion of

monoglycosylated dominant PrPSc type in addition to the

diglycosylated dominant pattern (data not shown).

Extensive strain typing of large numbers of individual

BSE-infected cattle either by biological or molecular

methods has not been reported.

Presumably, the different genetic background of the

different inbred mouse lines is crucial in determining

which prion strain propagates on BSE inoculation. The

transgenic mice described here have a mixed genetic

background with contributions from FVB/N, C57BL/6 and

129Sv inbred lines; each mouse will therefore have a

different genetic background. This may explain the

differing response of individual 129MM Tg35 mice, and

the difference between 129MM Tg35 and 129MM Tg45

mice, which are, like all transgenic lines, populations

derived from single founders. Indeed, the consistent

distinctive strain propagation in FVB and C57BL/6 versus

SJL and RIIIS lines may allow mapping of genes relevant

to strain selection and propagation, and these studies
are in


That different prion strains can be consistently isolated

in different inbred mouse lines challenged with BSE

prions argues that other species exposed to BSE may

develop prion diseases that are not recognizable as being

caused by the BSE strain by either biological or molecular

strain typing methods. As with 129MM Tg35 mice, the

prions replicating in such transmissions may be

from naturally occurring prion strains. It

remains of considerable concern whether BSE has transmitted

to, and is being maintained in, European sheep

¯ocks. Given the diversity of sheep breeds affected by

scrapie, it has to be considered that some sheep might have

become infected with BSE, but propagated a distinctive

strain type indistinguishable from those of natural sheep

scrapie. ...

The EMBO Journal Vol. 21 No. 23 pp. 6358±6366, 2002

6358 ãEuropean Molecular Biology Organization

J Neuropsychiatry Clin Neurosci 17:489-495, November 2005
doi: 10.1176/appi.neuropsych.17.4.489
© 2005 American Psychiatric Publishing, Inc.

Psychiatric Manifestations of Creutzfeldt-Jakob
Disease: A 25-Year Analysis
Christopher A. Wall, M.D., Teresa A. Rummans, M.D.,
Allen J. Aksamit, M.D.,
Lois E. Krahn, M.D. and V. Shane Pankratz, Ph.D.
Received April 20, 2004; revised September 9, 2004;
accepted September 13,
2004. From the Mayo Clinic, Department of Psychiatry
and Psychology,
Rochester, Minnesota; Mayo Clinic, Department of
Neurology, Rochester,
Minnesota. Address correspondence to Dr. Wall, Mayo
Clinic, Department of
Psychiatry and Psychology, Mayo Building-W11A, 200
First St., SW, Rochester,
MN 55905; (E-mail).

This study characterizes the type and timing of
psychiatric manifestations
in sporadic Creutzfeldt-Jakob disease (sCJD).
Historically, sCJD has been
characterized by prominent neurological symptoms, while
the variant form
(vCJD) is described as primarily psychiatric in
presentation and course: A
retrospective review of 126 sCJD patients evaluated at
the Mayo Clinic from
1976-2001 was conducted. Cases were reviewed for
symptoms of depression,
anxiety, psychosis, behavior dyscontrol, sleep
disturbances, and
neurological signs during the disease course. Eighty
percent of the cases
demonstrated psychiatric symptoms within the first 100
days of illness, with
26% occurring at presentation. The most commonly
reported symptoms in this
population included sleep disturbances, psychotic
symptoms, and depression.
Psychiatric manifestations are an early and prominent
feature of sporadic
CJD, often occurring prior to formal diagnosis.



Historically, psychiatric manifestations have been
described as a relatively
infrequent occurrence in the sporadic form of
creutzfeldt-Jakob disease.
However, our findings suggest otherwise. In this study,
a vast majority of
the cases were noted to have at least one psychiatric
symptom during the
course of illness, with nearly one-quarter occurring in
the prodromal or
presenting phase of the illness. After comparing the
frequency of
neuropsychiatric symptoms in sporadic CJD to studies
describing the variant
form of CJD, we found that there are fewer clinical
differences than
previously reported.5-7 While the age of patients
with vCJD presentation
is significantly younger and the course of illness is
longer, the type and
timing of psychiatric manifestations appear similar
between these two
diseases. ...snip...

Personal Communication

-------- Original Message --------

Subject: re-BSE prions propagate as

either variant CJD-like or sporadic CJD Date: Thu, 28
Nov 2002 10:23:43

-0000 From: "Asante, Emmanuel A" To:

Dear Terry,

I have been asked by Professor Collinge to respond to
your request. I am

a Senior Scientist in the MRC Prion Unit and the lead
author on the

paper. I have attached a pdf copy of the paper for your
attention. Thank

you for your interest in the paper.

In respect of your first question, the simple answer
is, yes. As you

will find in the paper, we have managed to associate
the alternate

phenotype to type 2 PrPSc, the commonest sporadic CJD.

It is too early to be able to claim any further
sub-classification in

respect of Heidenhain variant CJD or Vicky Rimmer's
version. It will

take further studies, which are on-going, to establish
if there are

sub-types to our initial finding which we are now
reporting. The main

point of the paper is that, as well as leading to the
expected new

variant CJD phenotype, BSE transmission to the
129-methionine genotype

can lead to an alternate phenotype which is
indistinguishable from type

2 PrPSc.

I hope reading the paper will enlighten you more on the
subject. If I

can be of any further assistance please to not hesitate
to ask. Best wishes.

Emmanuel Asante

<> ____________________________________

Dr. Emmanuel A Asante MRC Prion Unit & Neurogenetics
Dept. Imperial

College School of Medicine (St. Mary's) Norfolk Place,

Tel: +44 (0)20 7594 3794 Fax: +44 (0)20 7706 3272 email: (until 9/12/02)

New e-mail: (active from now)


Human Prion Protein with

Valine 129 Prevents Expression

of Variant CJD Phenotype

Jonathan D. F. Wadsworth, Emmanuel A. Asante,

Melanie Desbruslais, Jacqueline M. Linehan, Susan Joiner,

Ian Gowland, Julie Welch, Lisa Stone, Sarah E. Lloyd,

Andrew F. Hill,* Sebastian Brandner, John Collinge.

Variant Creutzfeldt-Jakob disease (vCJD) is a unique
and highly distinctive

clinicopathological and molecular phenotype of human
prion disease

associated with infection with bovine spongiform
encephalopathy (BSE)-like

prions. Here, we found that generation of this
phenotype in transgenic mice

required expression of human prion protein (PrP) with
methionine 129.

Expression of human PrP with valine 129 resulted in a
distinct phenotype and,

remarkably, persistence of a barrier to transmission of
BSE-derived prions on

subpassage. Polymorphic residue 129 of human PrP
dictated propagation of

distinct prion strains after BSE prion infection. Thus,
primary and secondary

human infection with BSE-derived prions may result in
sporadic CJD-like or

novel phenotypes in addition to vCJD, depending on the
genotype of the prion

source and the recipient.



Characterization of two distinct prion strains

derived from bovine spongiform encephalopathy

transmissions to inbred mice

Sarah E. Lloyd, Jacqueline M. Linehan, Melanie Desbruslais,

Susan Joiner, Jennifer Buckell, Sebastian Brandner,

Jonathan D. F. Wadsworth and John Collinge


John Collinge

MRC Prion Unit and Department of Neurodegenerative
Disease, Institute of Neurology,

University College, London WC1N 3BG, UK

Received 9 December 2003

Accepted 27 April 2004

Distinct prion strains can be distinguished by
differences in incubation period, neuropathology

and biochemical properties of disease-associated prion
protein (PrPSc) in inoculated mice.

Reliable comparisons of mouse prion strain properties
can only be achieved after passage in

genetically identical mice, as host prion protein
sequence and genetic background are known

to modulate prion disease phenotypes. While multiple
prion strains have been identified in

sheep scrapie and Creutzfeldt-Jakob disease, bovine
spongiform encephalopathy (BSE) is

thought to be caused by a single prion strain. Primary
passage of BSE prions to different lines

of inbred mice resulted in the propagation of two
distinct PrPSc types, suggesting that two

prion strains may have been isolated. To investigate
this further, these isolates were

subpassaged in a single line of inbred mice (SJL) and
it was confirmed that two distinct prion

strains had been identified. MRC1 was characterized by
a short incubation time (110±3 days),

a mono-glycosylated-dominant PrPSc type and a
generalized diffuse pattern of PrP-immunoreactive

deposits, while MRC2 displayed a much longer incubation
time (155±1 days),

a di-glycosylated-dominant PrPSc type and a distinct
pattern of PrP-immunoreactive deposits

and neuronal loss. These data indicate a crucial
involvement of the host genome in modulating

prion strain selection and propagation in mice. It is
possible that multiple disease phenotypes

may also be possible in BSE prion infection in humans
and other animals.


Journal of General Virology (2004), 85, 2471-2478 DOI

Medical Sciences
Identification of a second bovine amyloidotic
spongiform encephalopathy: Molecular similarities with
sporadic Creutzfeldt-Jakob disease

Cristina Casalone *, Gianluigi Zanusso , Pierluigi
Acutis *, Sergio Ferrari , Lorenzo Capucci , Fabrizio
Tagliavini ¶, Salvatore Monaco ||, and Maria Caramelli *

*Centro di Referenza Nazionale per le Encefalopatie
Animali, Istituto Zooprofilattico Sperimentale del
Piemonte, Liguria e Valle d'Aosta, Via Bologna, 148,
10195 Turin, Italy; Department of Neurological and
Visual Science, Section of Clinical Neurology,
Policlinico G.B. Rossi, Piazzale L.A. Scuro, 10, 37134
Verona, Italy; Istituto Zooprofilattico Sperimentale
della Lombardia ed Emilia Romagna, Via Bianchi, 9,
25124 Brescia, Italy; and ¶Istituto Nazionale
Neurologico "Carlo Besta," Via Celoria 11, 20133 Milan,

Edited by Stanley B. Prusiner, University of
California, San Francisco, CA, and approved December
23, 2003 (received for review September 9, 2003)

Transmissible spongiform encephalopathies (TSEs), or
prion diseases, are mammalian neurodegenerative
disorders characterized by a posttranslational
conversion and brain accumulation of an insoluble,
protease-resistant isoform (PrPSc) of the host-encoded
cellular prion protein (PrPC). Human and animal TSE
agents exist as different phenotypes that can be
biochemically differentiated on the basis of the
molecular mass of the protease-resistant PrPSc
fragments and the degree of glycosylation.
Epidemiological, molecular, and transmission studies
strongly suggest that the single strain of agent
responsible for bovine spongiform encephalopathy (BSE)
has infected humans, causing variant Creutzfeldt-Jakob
disease. The unprecedented biological properties of the
BSE agent, which circumvents the so-called "species
barrier" between cattle and humans and adapts to
different mammalian species, has raised considerable
concern for human health. To date, it is unknown
whether more than one strain might be responsible for
cattle TSE or whether the BSE agent undergoes
phenotypic variation after natural transmission. Here
we provide evidence of a second cattle TSE. The
disorder was pathologically characterized by the
presence of PrP-immunopositive amyloid plaques, as
opposed to the lack of amyloid deposition in typical
BSE cases, and by a different pattern of regional
distribution and topology of brain PrPSc accumulation.
In addition, Western blot analysis showed a PrPSc type
with predominance of the low molecular mass glycoform
and a protease-resistant fragment of lower molecular
mass than BSE-PrPSc. Strikingly, the molecular
signature of this previously undescribed bovine PrPSc
was similar to that encountered in a distinct subtype
of sporadic Creutzfeldt-Jakob disease.


C.C. and G.Z. contributed equally to this work.

||To whom correspondence should be addressed.

E-mail: .


Phenotypic Similarities Between BASE and sCJD. The

of CJD brains was initially demonstrated in primates
(27), and

classification of atypical cases as CJD was based on
this property

(28). To date, no systematic studies of strain typing
in sCJD have

been provided, and classification of different subtypes
is based

on clinical, neuropathological, and molecular features
(the polymorphic

PRNP codon 129 and the PrPSc glycotype) (8, 9, 15, 19).

The importance of molecular PrPSc characterization in

the identity of TSE strains is underscored by several

showing that the stability of given disease-specific
PrPSc types is

maintained upon experimental propagation of sCJD, familial

CJD, and vCJD isolates in transgenic PrP-humanized mice (8,

29). Similarly, biochemical properties of BSE- and

PrPSc molecules remain stable after passage to mice

expressing bovine PrP (30). Recently, however, it has been

reported that PrP-humanized mice inoculated with BSE

may also propagate a distinctive PrPSc type, with a

dominant'' pattern and electrophoretic mobility of the

unglycosylated fragment slower than that of vCJD and
BSE (31).

Strikingly, this PrPSc type shares its molecular
properties with the

a PrPSc molecule found in classical sCJD. This
observation is at

variance with the PrPSc type found in MV2 sCJD cases and in

cattle BASE, showing a monoglycosylated-dominant
pattern but

faster electrophoretic mobility of the
protease-resistant fragment

as compared with BSE. In addition to molecular properties

of PrPSc, BASE and MV2 sCJD share a distinctive pattern of

intracerebral PrP deposition, which occurs as
plaque-like and

amyloid-kuru plaques. Differences were, however,
observed in

the regional distribution of PrPSc. While inMV2 sCJD
cases the

largest amounts of PrPSc were detected in the cerebellum,

brainstem, and striatum, in cattle BASE these areas
were less

involved and the highest levels of PrPSc were recovered
from the

thalamus and olfactory regions.

In conclusion, decoding the biochemical PrPSc signature of

individual human and animal TSE strains may allow the

of potential risk factors for human disorders with

unknown etiology, such as sCJD. However, although BASE and

sCJD share several characteristics, caution is dictated
in assessing

a link between conditions affecting two different mammalian

species, based on convergent biochemical properties of

PrPSc types. Strains of TSE agents may be better

characterized upon passage to transgenic mice. In the

until this is accomplished, our present findings
suggest a strict

epidemiological surveillance of cattle TSE and sCJD
based on

molecular criteria.

[Docket No. 03-025IFA] FSIS Prohibition of the Use of Specified Risk Materials for Human Food and Requirement for the Disposition of Non-Ambulatory Disabled Cattle

Terry S. Singeltary

Page 1 of 17

From: Terry S. Singeltary Sr. []

Sent: Thursday, September 08, 2005 6:17 PM


Subject: [Docket No. 03-025IFA] FSIS Prohibition of the Use of Specified Risk Materials for Human Food and Requirements

for the Disposition of Non-Ambulatory Disabled Cattle

Greetings FSIS,

I would kindly like to submit the following to [Docket No. 03-025IFA] FSIS Prohibition of the Use of Specified Risk Materials for Human Food and

Requirements for the Disposition of Non-Ambulatory Disabled Cattle

THE BSE/TSE SUB CLINICAL Non-Ambulatory Disabled Cattle

Broken bones and such may be the first signs of a sub clinical BSE/TSE Non-Ambulatory Disabled Cattle ;



Issued: Monday, 28 August 2000



Terry S. Singeltary Sr.

P.O. Box 42

Bacliff, Texas USA 77518




PAGE 43;

Section 2. Testing Protocols and Quality Assurance Controls




Section 2. Testing Protocols and Quality Assurance Controls In November 2004, USDA announced that its rapid screening test, Bio-Rad Enzyme Linked Immunosorbent Assay (ELISA), produced an inconclusive BSE test result as part of its enhanced BSE surveillance program. The ELISA rapid screening test performed at a BSE contract laboratory produced three high positive reactive results.40 As required,41 the contract laboratory forwarded the inconclusive sample to the APHIS National Veterinary Services Laboratories (NVSL) for confirmatory testing. NVSL repeated the ELISA testing and again produced three high positive reactive results.42 In accordance with its established protocol, NVSL ran its confirmatory test, an immunohistochemistry (IHC) test, which was interpreted as negative for BSE. In addition, NVSL performed a histological43 examination of the tissue and did not detect lesions44 consistent with BSE. Faced with conflicting results, NVSL scientists recommended additional testing to resolve the discrepancy but APHIS headquarters officials concluded no further testing was necessary because testing protocols were followed. In our discussions with APHIS officials, they justified their decision not to do additional testing because the IHC is internationally recognized as the “gold standard.” Also, they believed that conducting additional tests would undermine confidence in USDA’s established testing protocols. However, OIG obtained evidence that indicated additional testing was prudent to ensure that USDA’s testing protocols were effective in detecting BSE and that confidence in USDA’s testing procedures was maintained. OIG came to this conclusion because the rapid tests produced six high positive reactive results, confirmatory testing conflicted with the rapid test results, and various standard operating procedures were not followed. Also, our review of scientific literature, other country protocols, as well as discussions with internationally recognized experts led us to conclude that confirmatory testing should not be limited when conflicting test results are obtained. To maintain objectivity and independence in our assessment, we requested the USDA Agricultural Research Service (ARS) perform the Office International des Epizooties (OIE) Scrapie-Associated Fibrils (SAF) 40 ELISA test procedures require two additional (duplicate) tests if the initial test is reactive, before final interpretation. If either of the duplicate tests is reactive, the test is deemed inconclusive. 41 Protocol for BSE Contract Laboratories to Receive and Test Bovine Brain Samples and Report Results for BSE Surveillance Standard Operating Procedure (SOP), dated October 26, 2004. 42 The NVSL conducted an ELISA test on the original material tested at the contract laboratory and on two new cuts from the sample tissue. 43 A visual examination of brain tissue by a microscope. 44 A localized pathological change in a bodily organ or tissue.
immunoblot.45 ARS performed the test at the National Animal Disease Center because NVSL did not have the necessary equipment46 (ultracentrifuge) to do the test. APHIS scientists observed and participated, as appropriate, in this effort. The additional tests conducted by ARS produced positive results. To confirm this finding, the Secretary requested the internationally recognized BSE reference laboratory in Weybridge, England, (Weybridge) to perform additional confirmatory testing. Weybridge conducted various tests, including their own IHC methods, as well as three Western blot methods. The tests confirmed that the suspect cow was infected with BSE. Also, Weybridge confirmed this case as an unequivocal positive case of BSE on the basis of IHC. As a result of this finding, the Secretary immediately directed USDA scientists to work with international experts to develop a new protocol that includes performing dual confirmatory tests in the event of another inconclusive BSE screening test. Finding 3 Rigid Protocols Reduced the Likelihood BSE Could be Detected APHIS relied on a single test method, as well as a histological examination of tissue for lesions consistent with BSE, to confirm the presence of BSE even though discrepant test results indicated further testing may be prudent. When IHC test results were interpreted as negative, APHIS concluded the sample tested negative for BSE. Subsequent independent tests initiated by OIG using a different testing method, as well as confirmatory testing by Weybridge, determined that the suspect sample was a positive case of BSE. APHIS Declares BSE Sample Negative Despite Conflicting Results When the tissue sample originally arrived at NVSL in November 2004 from the contract lab, NVSL scientists repeated the ELISA screening test and again produced three high positive reactive results. NVSL scientists cut out two sections of the brain sample for IHC testing. One section was used for an experimental procedure that was not part of the confirmatory testing protocol, and the other cut was for normal IHC testing using scrapie for a positive control.47 According to NVSL scientists, the experimental test results were inconclusive but the IHC test was interpreted as negative. The NVSL scientists were concerned with the inconsistencies and conducted 45 The OIE SAF immunoblot is an internationally recognized confirmatory test, often referred to as a Western blot test. There are different types of Western blots; the OIE SAF immunoblot includes enrichment steps taken with the sample prior to the standard Western blot steps. 46 APHIS has now ordered the necessary equipment for NVSL. USDA/OIG-A/50601-10-KC Page 32
47 A positive control is a sample that is known to contain a given disease or react in the test. The sample then can be used to make sure that the test for that disease works properly. In the case of BSE, tissue infected with either scrapie or BSE can serve as a positive control for an IHC test for BSE since both are different forms of the same disease (transmissible spongiform encephalopathy or TSE).
another IHC test using BSE as a positive control.48 The test result was also interpreted as negative. Also, according to the NVSL scientists, the histological examination of the tissue did not detect lesions consistent with BSE. After the second negative IHC test, NVSL scientists supported doing additional testing. They prepared a plan for additional tests; if those tests had been conducted, BSE may have been detected in the sample. The additional tests recommended by NVSL scientists, but not approved by APHIS Headquarters officials, were the IHC using other antibodies (IHC testing using different antibodies ultimately produced positive results); IHC testing of additional regions of the brain (the cerebellum tested positive); regular and enriched (OIE-like) Western blots (the obex and cerebellum tested positive); and variable rapid tests (the obex and cerebellum tested positive with two different rapid tests). NVSL officials also recommended that the sample be sent to Weybridge for confirmatory testing (to conduct IHC and OIE Western blot tests). In June 2005, Weybridge conducted IHC testing with three different antibodies, including the antibody used in the United States (tested positive), the OIE Western blot (tested positive), a modified commercial kit Western blot (negative) and the NaPTA49 Western blot (tested positive). We obtained information as to the differing protocols used by other countries. We found that while APHIS determined that additional testing was unnecessary after the IHC test, other countries have used multiple tests to confirm positives. In Japan, for example, all reactive screening test samples are examined by both IHC and a Western blot (different from the OIE SAF immunoblot). In the United Kingdom (U.K.), IHC and Western blot (different from the OIE SAF immunoblot) tests are used for all animals that test positive with a screening test. When IHC and the Western blot fail to confirm a positive rapid test, the U.K. resorts to a third test, the OIE SAF immunoblot. With these procedures in place, both Japan and the U.K. have found BSE cases that were rapid test reactive, IHC negative, and finally confirmed positive with a Western blot. Evidence Indicated Additional Testing Would Be Prudent We also spoke with an internationally recognized BSE expert regarding the advisability of limiting confirmatory testing when conflicting results are obtained. This official expressed concern about limiting confirmatory tests to the IHC despite its status as one of the “gold standard” tests. He advised that the IHC is not one test; it is a test method that can vary significantly in sensitivity from laboratory to laboratory. New antibodies can improve or
USDA/OIG-A/50601-10-KC Page 33
48 The NVSL uses scrapie as the positive control as part of its normal IHC testing procedures. Due to the conflicting results between the ELISA and IHC tests, the NVSL conducted another IHC test with BSE as the positive control. Subsequently, the NVSL modified the Confirming Inconclusive Results from BSE Testing Laboratories at the NVSL SOP to show that all IHC tested BSE inconclusive samples from contract laboratories will use BSE as the positive control. 49 Sodium phosphotungstic acid.
USDA/OIG-A/50601-10-KC Page 34
reduce sensitivity, as can variations in many of the reagents50 used. He explained that his laboratory had experienced cases where an initial confirmatory IHC test was challenged by either a more extensive IHC test or “…applying a more sensitive immunoblot.” He emphasized the importance of having additional confirmatory testing to resolve discrepant results since there are many variables, and most of the variability appears to be due to test performance of the laboratory. OIG became concerned that APHIS relied on its confirmatory test methods when rapid screening tests produced high positive reactive results six times.51 Also, we found that APHIS did not pursue and/or investigate why the ELISA produced high reactive positives. An official from the manufacturer of the ELISA test kit told us that they requested, but did not receive, information on the inconclusive reported by USDA in November 2004. These officials requested this information in order to understand the reasons for the discrepant results. The Bio-Rad ELISA rapid screening test is internationally recognized as a highly reliable test and is the rapid screening test used for USDA’s surveillance effort. According to APHIS officials, they felt it would be inappropriate to collaborate on the one sample because Bio-Rad is a USDA-APHIS regulated biologics company and only one of several competing manufacturers. To maintain confidence in USDA’s test protocols, it would have been a prudent course of action for USDA to determine why such significant differing results were obtained. The fact that they did not pursue this matter caused concerns relating to testing quality assurance procedures. In this regard, we found lack of compliance with SOPs relating to laboratory proficiency and quality assurance (see Finding 4), and, in this case, the storage of sampled material and reporting of test results. We found that the NVSL did not prepare a report to document its confirmatory testing of the November 2004 sample. The SOP52 states that the BSE network laboratory initiating the inconclusive will receive a report of the case. NVSL officials could not explain why a final report had not been prepared. We also found that the inconclusive sample was frozen prior to IHC confirmatory testing. APHIS protocols state that samples are not to be frozen prior to laboratory submission. The OIE Manual of Diagnostic Tests and Vaccines for Terrestrial Animals states that the tissues for histological or IHC examination are not to be frozen as this will provide artefactual53 lesions that may compromise the identification of vacuolation,54 and/or target site location. Although the sample was frozen, APHIS did not conduct a Western 50 A substance used in a chemical reaction to detect, measure, examine, or produce other substances. 51 The six high positive reactive results were from three tests of the submitted sample (multiple runs of the same test). 52 Confirming Inconclusive Results from Bovine Spongiform Encephalopathy Testing Laboratories at the NVSL SOP, dated August 13, 2004. 53 A structure or feature not normally present but visible as a result of an external agent or action, such as one seen in a microscopic specimen after fixation. 54 A small space or cavity in a tissue.
USDA/OIG-A/50601-10-KC Page 35
blot test on the sample. An NVSL official said freezing the sample does not make it unsuitable for IHC. APHIS determined that the sample was suitable for IHC and therefore, in accordance with its SOP, did not conduct a Western blot test. APHIS also handled the December 2003 BSE positive differently than the November 2004 sample. For the December 2003 BSE positive sample, APHIS conducted several confirmatory tests in addition to the IHC testing and histological examination (unlike the November 2004 sample tests, both of these were interpreted as positive). ARS performed two Western blots (Prionics Check Western blot and an ARS developed Western blot). When we questioned why the samples were handled differently, APHIS officials stated that the Western blots were done because the IHC in December 2003 was positive. The additional testing was done to further characterize the case, because it was the first U.S. case; the additional testing was not done to decide whether the case was positive or negative. We discussed our concerns with limiting confirmatory testing, particularly given conflicting results, with the APHIS Administrator and staff in May 2005. He explained that international standards recognized more than one “gold standard” test. In setting up its testing protocols, USDA had chosen one as the confirming test, the IHC test, and stayed with it. APHIS protocols only allow a Western blot in cases where the sample has become unsuitable for IHC tests (e.g., in cases where the brainstem architecture is not evident). International standards, he continued, accept a tissue sample as negative for BSE if its IHC test is negative. Once the test is run in accordance with protocols, additional tests undermine the USDA testing protocol and the surveillance program. He concluded that since APHIS’ protocols accepted the IHC test as confirming the presence or absence of BSE, no further testing was necessary. According to protocol, the tissue sample was determined to have tested negative for BSE. On June 24, 2005, USDA announced that the additional testing by the BSE reference laboratory in England confirmed the presence of BSE in the tissue sample. To obviate the possibility that a future sample would be declared negative and then found positive, the Secretary of Agriculture announced a change to APHIS’ testing protocols that same day. He called for “dual confirmatory tests in the event of another ‘inconclusive’ [reactive] BSE screening test.” He also indicated that he would reinforce proper procedures so that samples will not be frozen, and to spot-check the laboratories to see that they complete reports as required. APHIS issued a SOP on the new confirmatory testing protocols on November 30, 2005.
USDA/OIG-A/50601-10-KC Page 36
Recommendation 5 Continuously re-evaluate, and adjust, testing protocols based on emerging science. .......




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