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From: TSS (216-119-132-46.ipset12.wt.net)
Subject: IFST updated Information Statement on BSE and Variant Creutzfeldt-Jakob Disease (vCJD)
Date: October 28, 2004 at 8:27 am PST

-------- Original Message --------
Subject: IFST updated Information Statement on BSE and Variant Creutzfeldt-Jakob Disease (vCJD)
Date: Thu, 28 Oct 2004 10:33:17 -0500
From: "Terry S. Singeltary Sr."
Reply-To: Bovine Spongiform Encephalopathy
To: BSE-L@UNI-KARLSRUHE.DE

Institute of Food Science & Technology 28.10.2004
IFST updated Information Statement on BSE and Variant Creutzfeldt-Jakob
Disease (vCJD)


Bovine Spongiform Encephalopathy (BSE) and Variant Creutzfeldt-Jakob
Disease (vCJD) In Humans

The Institute of Food Science & Technology, through its Public Affairs
and Technical & Legislative Committees, has authorised the following
Information Statement, dated October 2004, replacing the Statement of
October 2001 and any previous version.

Special Note

This updated Information Statement takes account of available data and
published research up to September 2004. As with the previous update, in
order to accommodate much new material without extending the length,
some of the earlier material which has become of historical rather than
of current interest has been eliminated or curtailed, but literature
references from that period that remain relevant have been retained.

Summary

BSE background: An outline is given of the background to BSE, its origin
and transmission in cattle. While there is strong evidence that the
cause of the UK BSE epidemic was the feeding of infected meat and bone
meal (MBM) to cattle, it will probably never be proved or provable
whether the infection originated from MBM made from scrapie infected
sheep or from MBM made from a hypothetical cow with a rare sporadic TSE.

BSE incidence: The continued dramatic year-on-year fall in the number of
new clinical cases of BSE in Great Britain (from the peak of 36,680 in
1992, to 1,311 in 2000, is as was forecast and on track to bring the
epidemic to an end. Note that data for subsequent years (781 in 2001,
445 in 2002, 174 in 2003) are not strictly comparable with earlier data
because the large number of UK cattle killed and either buried or
incinerated on pyres during the 2001 UK foot and mouth disease outbreak
must have included an unknown number incubating BSE. In addition to a
total of 179,093 clinical cases (passive surveillance), active
surveillance post-mortem testing since 1999 has revealed a total of
1,514 cases (to 7 September 2004) and 3,295 cases (to 9 September 2004)
in the rest of the world, in apparently healthy cattle, the latter most
likely resulting from feeding to cattle UK mammalian MBM imported as pig
and poultry feed prior to 1996. It is possible that cases may emerge in
other countries which imported this material. WHO has stated that over
100 countries are at risk. The EU Commission publishes an updated table
of incidence in EU countries, and the OIE maintains an updated world
list, by countries.

The infective agent in transmissible spongiform encephalopathies:
Evidence continues to mount in support of the prion hypothesis, as does
the body of research consistent with it and inconsistent with other
hypotheses. Strong confirmation has been offered by separate lines of
research demonstrating conversion of normal cellular prion protein to
the infective form. This does not preclude the influence or triggering
effect of other factors. The role of copper and zinc ions in prion
conformation has been demonstrated and the possible role of manganese in
change of conformation has been mooted. Two lines of research have also
shown that multiple prion strains are compatible with the prion hypothesis.

Prion infectivity and transmission mode: Although research indicates
that the lymph system plays an important part in the transmission of
infectivity to the central nervous system (CNS) the exact mechanisms by
which this occurs are insufficiently understood.

Infectivity of bovine materials: Links to a series of Opinions by the EU
Scientific Steering Committee on the infectivity of various bovine
materials derived from BSE-infected cattle may be found at
http://europa.eu.int/comm/food/fs/bse/scientific_advice08_en.html

Beef, milk and bones: Mouse assay tests have not detected BSE
infectivity in muscle meat (beef) or milk from confirmed BSE cows. It is
not yet known if beef or milk from BSE-infected cows contain amounts of
BSE infectivity too small to be detected by mouse assay. The results of
assay experiments in cattle will not be known until 2007. Current risk
from beef or milk is considered to be extremely small. Experiments have
detected infectivity in the dorsal root ganglia, the trigeminal ganglia
and the bone marrow. In regard to the latter, risk assessment indicated
that the added risk involved to people eating beef is extremely low,
about one new case of new variant CJD in a billion years per person.
However the risk estimate has a wide range of uncertainty. The then UK
Government responded by banning the sale of bone-in beef, but the ban
was eventually lifted.

Mechanically recovered meat (MRM): Attention has focused on MRM as a
probable source of high titre infectivity in the food chain,
particularly prior to 1995 when the UK use of spinal column for MRM was
banned. Many years later an intuitive supposition was mooted that cheap
meat products more likely to contain MRM had been consumed much more in
Scotland and the North of England than in the South could explain the
significantly greater incidence of vCJD in the former than the latter.
Though the supposition appeared, on examination of consumption
statistics, to be erroneous, nevertheless it gave rise to two projects
retrospectively attempting to determine quantitative MRM usage in
various meat products in the earlier period. Current EU measures
prohibit MRM from any bovine or ovine bones.

Gelatin and tallow: In its updated reports, the EU Scientific Steering
Committee carried out risk assessments of various raw materials and
production processes for gelatin (March 2003) and tallow (April
2003)respectively.

Blood: Although infectivity had not been found by mouse assay in blood
of BSE-infected cattle, in September 2003 the EU Scientific Steering
Committee issued an updated Opinion taking account of the implications
of the then recent papers on transmission of BSE by blood transfusion in
sheep.

Early UK controls

The early measures in the UK for control of the epidemic in cattle were:

to slaughter and destroy animals clinically diagnosed on the farm or
elsewhere (from 1988);
to prohibit the feeding of material containing animal protein derived
from ruminants to cattle and other ruminants (1988):
to prohibit Specified Bovine Offals (SBOs) from the food or feed chain

The first and third of these served, of course, also as part of the
precautionary programme of measures to protect human health, in case
transmissibility to humans might occur.

UK controls from mid-1996: From August 1996 strict enforcement of the
ban on mammalian MBM for all farm animals, exclusion of SRMs from the
food chain, and slaughter of cattle aged over 30 months (the OTMS) plus
a cattle traceability scheme led to the lifting in November 1998 of the
EU-imposed global ban on British beef exports, on the basis of the
monitored enforcement of the existing UK controls plus fulfillment of
the requirements of the Florence Agreement by the Date-Based Export
Scheme (DBES) and cull of offspring born on or after 1 August 1996 to
BSE-infected dams.

During 2000, the FSA held a series of open Stakeholders Meetings at
which a thorough review was carried out of the BSE controls [Specific
Risk Materials (SRMs), the MBM ban and the Over Thirty Months Scheme
(OTMS)] resulting in recommendations to the Prime Minister, which were
accepted, for the retention, strengthening and enforcement of the
controls. In 2004, with the testing at slaughter of all cattle over 28
months, the value of the OTMS has been reviewed.

BSE controls across the EU: In December 2000, the EU Council of
Ministers decided on new controls across the EU Member States,
essentially similar to the UK controls referred to above, but with
post-mortem testing of suspect castle over 30 months from January 2001
and of all over 30 months cattle, and some categories of over 24 months
cattle from 1 July 2001. Tests are mostly being carried out by the
Prionics or Bio-Rad methods. From January 2001 to end of May 2001, EU
Member States had tested over 2.4 million apparently healthy cattle,
mainly aged over 30 months, of which 90 were found positive for BSE.
Prior to 1 July 2001 testing was not carried out in the UK because under
the OTMS provisions such cattle are slaughtered and not permitted to
enter the food chain. From 1 July, the UK began testing of some
categories and later extended the testing. On 7 February 2001, the
European Commission agreed three proposals: to require the removal of
the vertebral column from all cattle over 12 months and to prohibit
mechanically recovered meat from bones of ruminants; new requirements to
pressure-cook rendered animal fats from ruminants for food and feed; and
authorising certain hydrolysed proteins from fish and feathers.

Diagnostic tests: The EU Commission has approved five rapid postmortem
methods for testing for BSE in cattle and ten more are under evaluation.
A number of possible ante mortem tests have been proposed for cattle and
for humans but so far none has been officially accepted. A problem of
any ante mortem method is lack of knowledge of the stage of incubation
at which infectivity is detectable.

BSE developments outside Europe: The occurrence of the first of (now) 11
cases of BSE in Japan in September 2001, a single case in Canada in
January 2003 and a single case (of Canadian origin) in USA in December
2003, has led to new concerns and a range of new measures in those
countries.

BSE risk by countries or regions: The EU Scientific Steering Committee
has issued a series of Reports giving its opinion on the geographical
BSE risk (GBR) together with detailed assessment reports for various
countries. GBR is not an indicator of a risk to humans via food
consumption, but a qualitative indicator of the risk that live cattle
could be infected with the BSE agent and incubating the disease. The
analysis is based on a qualitative model developed by the SSC that was
applied to information provided voluntarily by these countries. Among
major considerations are whether live cattle or MBM have been imported
from what were at the time high risk countries, especially the UK, and
the time and effectiveness of risk management measures. Countries were
assessed in four Categories:

Category I: Highly unlikely to present a BSE risk
Category II: Unlikely, but a BSE risk cannot be excluded
Category III: Likely to present a BSE risk, even if not confirmed, or
presenting a low level of confirmed BSE risk
Category IV: BSE risk confirmed at a high level

In August 2004 the European Food Safety Authority (EFSA) issued reports
of reassessment of some countries.

Vertical transmission of BSE? The EU Scientific Steering Committee at
its meeting of 18-19 March 1999 adopted an Opinion on the possible
vertical transmission of Bovine spongiform encephalopathy (BSE)
(amended May 2002). Subsequent research gives no support to the
occurrence of vertical transmission.

BASE: Atypical cases of BSE in individual cattle have been found in
Japan, France, Italy, the Netherlands, Belgium, Denmark and Poland. This
appears to be a second cattle TSE which has been named bovine
amyloidotic spongiform encephalopathy (BASE).

BSE in sheep? Fears that BSE may be present in sheep but masked by
scrapie led to precautionary legislation in August 1996 (updated and
extended in April 2002) to exclude from the food chain sheep (and goat)
tissues corresponding to Specified Bovine Materials. There is no
evidence of presence, but if it is present, and behaves in sheep like
scrapie, it could involve far more tissues being infected than in
cattle, both vertical and horizontal transmission, and infection of
pastures. There is as yet no rapid test to distinguish BSE from scrapie
in sheep. The full extent of scrapie in EU flocks is unknown. On 2 June
2004 DEFRA issued a consultation document on Contingency plan for the
emergence of naturally occurring BSE in sheep.

BSE in primates: Examination of the pattern of prion distribution and
brain degeneration in 20 euthanised lemurs from three different French
primate centres, all of whom had been fed beef protein dietary
supplements, was virtually identical to that seen in experimentally
infected lemurs. The results suggest that BSE infection of zoo and
breeding centre primates may have been more widespread than previously
thought

BSE/vCJD: From research published from October 1996 onwards, scientific
evidence has been accumulating that BSE infectivity and variant CJD
(vCJD) infectivity carry the same "fingerprint". Although the scientific
evidence does not prove a causal connection, the evidence is consistent
with the transmissibility of BSE infectivity to at least some humans
(possibly to all humans but at varying incubation rates); and taken in
conjunction with related circumstances it increases the likelihood of a
causal connection. It is theoretically possible that both BSE and vCJD
may have been triggered by some third presently unsuspected cause, but
it is difficult to conceive what that might be. On 28 September 2001,
the UK Department of Health announced a 55 million compensation package
for families of vCJD victims.

vCJD incidence: The UK Department of Health News Release of 6 September
2004, gives a cumulative total number of definite and probable cases of
vCJD to date as 149 (including 5 who are still alive). There are fifteen
definite and probable cases outside the UK, three of whom have had UK
connections. Assuming the likelihood that most cases of vCJD so far are
the result of having consumed BSE infective materials, mainly prior to
1989, however, although attempts have been made to estimate minimum and
maximum figures (widely apart) it is still not possible to draw from the
figures to date any long-term conclusions, whether optimistic or
pessimistic, as to likely future incidence. Although the present wave
is showing a significant decline since the peak in 2002, and some have
tried to draw optimistic conclusions from this, research indicates there
may be more waves to come, plus cases from transfusion of blood from
infected donors or from the use of infected surgical instruments.

Tonsil biopsy survey: Tonsil biopsy has been shown to obviate the need
for brain biopsy for ante mortem diagnosis of vCJD. In a testing of
12,674 samples of (mainly) appendicectomies and some tonsillectomies,
three appendicectomy samples showed lymphoreticular accumulation of
prions, giving a estimated prevalence of 237 per million (95% CI 49-692
per million). The pattern of lymphoreticular accumulation in two of
these samples was dissimilar from that seen in known cases of vCJD. A
much larger test, of tonsils from 100,000 patients, may give a better
picture.

Blood (human): Research reports, including the finding of infectivity in
the tonsils of vCJD victims, and evidence showing that the lymph system
is involved in passage of infectivity from gut to brain, implicate the
lymphoreticular system, and suggest the possibility that circulating
lymphocytes in the blood may carry infectivity. This led to adoption of
the leucodepletion of blood supplies in November 1997 as a precautionary
measure. However, research has now suggested that leucodepletion removes
only 42% of the initial TSE infectivity from whole blood. While further
work is needed to identify the location of the residual infectivity, it
was presumed that it is plasma associated.

Following a case in December 2003 of vCJD possibly acquired by a 1999
blood transfusion, a second case of possible transmission of vCJD from
person to person via a 1999 blood transfusion was reported [Peden, AH et
al, (2004) A patient in the UK received a blood transfusion in 1999 from
a donor who later went on to develop vCJD. The patient died of causes
unrelated to vCJD but a post mortem revealed the presence of vCJD
infectivity in the patients spleen. This was the first instance of vCJD
in a person in the codon 129 heterozygous (met/val) group.

Therapeutic/prophylactic agents? Prusiners group (Korth et al (2001)
have reported that tricyclic derivatives of acridine and phenothiazine
exhibit half-maximal inhibition of PrPSc formation at effective
concentrations (EC50) between 0.3 M and 3 M in cultured cells
chronically infected with prions. Because quinacrine and chlorpromazine
have been used in humans for many years as antimalarial and
antipsychotic drugs, respectively, and are known to pass the blood-brain
barrier, they suggest that they are immediate candidates for the
treatment of CJD and other prion diseases. However, following media
reports in August 2001 that two vCJD victims have been treated and that
one has shown remission, Prusiner has stated (10 October 2001) that one
has died and the other has become worse. However, In August 2004 the UK
Medical Research Council is officially launching the "PRION-1" trial, a
trial of potential treatments. After four years of debate over which to
test, it will focus on quinacrine, The National Prion Disease Clinic at
St Marys Hospital in London has already given the drug to around 20
patients, but the results are not yet published.

Also from within Prusiners group comes a report that several antibodies
cleared prion clumps out of cultured mouse brain cells. seeming to
interrupt the conversion of normal prions by malignant ones.

There is some scientific evidence that compounds in the pentosan
polysulphate (PPS) group might have potential for use as prophylactic
agents against vCJD in humans. In the absence of further data on
efficacy and safety, SEAC and the UK Department of Health did not
consider that it was justified to recommend the wide use of PPS as a
possible prophylactic against vCJD. In certain circumstances, where
there is a tangible risk as a consequence of direct exposure to
infectivity (such as an accident in a laboratory), there might be a case
for administration of PPS. However, in June 2003 it was reported that,
after the father of a vCJD victim at an advanced stage took the hospital
concerned to court and after several months the court decided that the
operation should go ahead, treatment with PPS had an unexpectedly
beneficial result.

Official Inquiry into BSE and CJD: IFST welcomed the announcement of the
official independent inquiry into BSE, its terms of reference and the
open way in which it was to be conducted. IFST made a written submission
to the Inquiry.

The Final Report, evidence and witness statements all appear on the BSE
Inquiry Web site http://www.bseinquiry.gov.uk/

The Inquiry Report, dealing with UK events up to 1996, identified
problems of excessive Government secrecy and unjustified public
reassurances; inadequate communication among Government Departments;
inadequate handling of hazard and uncertainty; lack of foresight that
BSE might cause vCJD and of planning for that eventuality, lack of
correct use of scientific advisory committees; ineffective enforcement
of the control measures; inadequate coordination of research. Measures
since March 1996, and not least the creation of the Food Standards
Agency, have gone a long way to rectifying these deficiencies. The UK
Governments final Response to the Report of the BSE Inquiry
http://www.defra.gov.uk/animalh/bse/general/response.pdf was published
on 28 September 2001.

Much still remains unknown: The following are among the principal gaps
in scientific knowledge to date:

There is no treatment or cure for BSE or vCJD;
As previously indicated, although research is giving increasing
evidence of pathogenesis pathways the exact mechanisms of transmission
of infectivity to the central nervous system are insufficiently understood;
There is no rapid ante-mortem diagnostic test for BSE or vCJD;
It is not known at what stage of incubation a BSE-incubating cow gives
a positive result in a post-mortem test or would give a positive result
in an ante-mortem test if one existed;
It is not known yet whether muscle meat or milk carry infectivity at
too low a level to be measured or detected by existing methods;
it is not known whether BSE exists in the sheep flock;
Assuming a causal relationship between vCJD and oral consumption of
BSE infectivity, it is not known what is the infective dose, or whether
it is a single dose or cumulative;

Research needs: The foregoing areas where knowledge is lacking or
inadequate clearly indicate the priority needs for research to fill
those gaps.

Every successive update of this Information Statement has emphasised

"While that sums up the present state of knowledge, scientists always
have to keep open minds. They have to act on existing knowledge while
recognising that further research will bring new information and
knowledge, which may in turn lead to revised conclusions. We welcome the
devotion of substantial extra resources to research in this field."

To read the full text (68 pages) visit http://www.ifst.org/hottop5.htm

Glossary of abbreviations

BAB  (cattle) born after the ban (on ruminant feed for ruminants)
BARB  born after the reinforced or real) ban in August 1996
BSE  bovine spongiform encephalopathy
CFIA  Canadian Food Inspection Agency
CJD  Creutzfeldt-Jakob disease
CJDSU  CJD Surveillance Unit
CTS  cattle traceability scheme
CVL  Central Veterinary Laboratory (now the Veterinary Laboratory Agency)
DBES  Date-Based Export Scheme
DEFRA  UK Department for Environment, Food and Rural Affairs
DoH  UK Department of Health
EFSA  European Food Safety Authority
FMD  foot and mouth disease
FDA  US Food and Drug Administration
FSA  UK Food Standards Agency
HPA  Health Protection Agency
i/c  intra-cerebral
MAFF  former UK Ministry of Agriculture, Fisheries and Food
MBM  meat and bone meal
MRM  mechanically recovered meat
OIE  World Organisation for Animal Health
OTMS  Over Thirty Month Scheme
PrP  prion protein
PrPc  normal cellular prion protein
PrPsc  (Infective) prion
SEAC  Spongiform Encephalopathy Advisory Committee
SBO  Specified Bovine Offal
SBM  Specified Bovine Material
SRM  Specified Risk Material
TSE  transmissible spongiform encephalopathy
nvCJD  new variant CJD, term used by CJDSU in 1996 to describe the
original ten cases
vCJD  alternative for (new) variant CJD. (Note: At its meeting on 18
March 1999, (SEAC) agreed that vCJD should be used in preference to
nvCJD in line with current practice in many scientific journals.
Although this designation has been a subject of criticism on the grounds
that it implies only one variant, for consistency vCJD is used
throughout this Information Statement, even when quoting papers or
statements in which nvCJD was used).
USDA  US Department of Agriculture
VLA  Veterinary Laboratory Agency (formerly Central Laboratory Agency)

Weitere Informationen: www.ifst.org
europa.eu.int/comm/food/fs/bse/scientific_advice08_en.html


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http://www.innovations-report.de/html/berichte/agrar_forstwissenschaften/bericht-35461.htmltss

Greetings,

> BASE: Atypical cases of BSE in individual cattle have been found in
> Japan, France, Italy, the Netherlands, Belgium, Denmark and Poland.
> This appears to be a second cattle TSE which has been named bovine
> amyloidotic spongiform encephalopathy (BASE).


funny how this report fails to mention the most important aspect of this
study;

MOLECULAR SIMILARITIES WITH SPORADIC CJD !

nope, they cannot even bring themselves to say it $

THE new findings of BASE in cattle in Italy of Identification of a
second bovine amyloidotic spongiform encephalopathy: Molecular
similarities with sporadic Creutzfeldt-Jakob disease


http://www.pnas.org/cgi/content/abstract/0305777101v1

and of coure the MARSHORIZING OF Collinge et al, for there work
about sporadic CJD ;

BSE prions propagate as either variant CJD-like or sporadic CJD-like
prion strains in transgenic mice expressing human prion protein

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 1
Corresponding author e-mail: j.collinge@prion.ucl.ac.uk


Received August 1, 2002; revised September 24, 2002; accepted October
17, 2002

Abstract


Variant CreutzfeldtJakob 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 indistinguishable from that of
sporadic CJD with PrPSc type 2. These data suggest that more than one
BSE-derived 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...

http://embojournal.npgjournals.com/cgi/content/full/21/23/6358

and heavens to betsy, no way scrapie transmits to humans, even though
it transmits to primates, BUT wait, what have we here;

Adaptation of the bovine spongiform encephalopathy agent to primates
and comparison with Creutzfeldt- Jakob disease: Implications for
human health

THE findings from Corinne Ida Lasmzas*, [dagger] , Jean-Guy Fournier*,
Virginie Nouvel*,

Hermann Boe*, Domnque Marc*, Franois Lamoury*, Nicolas Kopp [Dagger

] , Jean-Jacques Hauw, James Ironside, Moira Bruce [||] , Dominique

Dormont*, and Jean-Philippe Deslys* et al, that The agent responsible
for French iatrogenic growth hormone-linked CJD taken as a control is
very different from vCJD but is similar to that found in one case of
sporadic CJD and one sheep scrapie isolate;

http://www.pnas.org/cgi/content/full/041490898v1

it's not about science anymore folks, it's all politics........TSS






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