Scrapie reduction unlikely without effective breeding programme
30 July 2014
Over the last ten years Classical scrapie in sheep has decreased in
countries where breeding programmes for resistance were effectively implemented,
say EFSA experts.
EFSA has assessed the state of scrapie in the EU since the introduction ten
years ago of a series of measures to monitor and control the disease. Scrapie is
a fatal disease that affects sheep and goats. It belongs to the same family of
diseases as bovine spongiform encephalopathy (BSE) which is found in cattle and
is commonly known as mad cow disease. There is no evidence that scrapie has ever
been transmitted to humans. The infectious agent is thought to be an abnormal
form of a protein, also called a prion.
Experts of EFSA’s Panel on Biological Hazards have concluded that an
eradication policy that relies only on the detection and culling of infected
flocks and does not include breeding programmes for resistance is unlikely to
succeed. This is both because of the characteristics of this disease and because
the classical scrapie agent can persist in the environment for years.
“Sheep with a particular genetic makeup are resistant to Classical scrapie
and breeding choices allow an increase in the flock’s resistance to the disease”
explains Giuseppe Ru, Chair of EFSA’s Working Group on scrapie situation in the
EU.
EFSA experts concluded that Classical scrapie in sheep may die out if the
percentage of resistant sheep is above a certain threshold.
Occurrence of Classical scrapie varies greatly across the EU and its
evolution over time should be considered country-by-country. Overall, it has
been reported in 17 Member States; in some of them cases have decreased over
time, while in others no clear trend was observed.
EFSA experts recommend strengthening surveillance activities to detect
infected flocks and control the disease, increasing the implementation of
breeding programmes for resistance in sheep and starting their use in goats
too.
Scientific Opinion on the scrapie situation in the EU after 10 years of
monitoring and control in sheep and goats
--------------------------------------------------------------------------------
Notes to editors:
Scrapie comes in two variants. Classical scrapie is transmitted through
exposure to scrapie-infected animals (e.g. via milk or placentae) and their
environment. Scientific evidence suggests that Atypical scrapie, the second
variant, is spontaneous and non-contagious. In this opinion EFSA experts have
considered both variants, with a particular focus on Classical scrapie. For
media enquiries please contact: EFSA Media Relations Office Tel. +39 0521 036
149 E-mail: Press@efsa.europa.eu
INTRODUCTION - Surveillance (Part 1)
Regulatory Scrapie Slaughter Surveillance (RSSS)
RSSS started April 1, 2003. It is a targeted slaughter surveillance program
which is designed to identify infected flocks. Samples have been collected from
430,085 animals since April 1, 2003. There have been 473 NVSL confirmed positive
animals* (465 classical cases and 8 Nor98-like cases) since the beginning of
RSSS. As of June 30, 2014, 32,173 samples have been collected in FY 2014, 26,408
from sheep and 5,765 from goats. As of June 30, 2014, 2 white-faced and 2
black-faced sheep have tested positive for scrapie in FY 2014. The percentage of
samples that have tested positive for each face color from FY 2003 through FY
2014 is depicted in Chart 3. In November 2013, administrative units within APHIS
Veterinary Services reorganized from 2 Regions to 6 Districts (Figure 1). The
distribution of sheep and goat populations by District is depicted in Chart 4a.
The number of animals collected for FY 2014 by District where collected is shown
in Chart 4b. A monthly comparison of RSSS collections by fiscal year is
displayed in Chart 5. Chart 6 is a retrospective 6-month rolling average of the
percent positive, black-faced sheep sampled at RSSS collection sites.
*RSSS positives are reported based on collection date and may have been
confirmed after June 30, 2014.
INTRODUCTION - Surveillance (Part 2) On-Farm Surveillance Testing sheep and
goats in the field is an essential part of scrapie surveillance, and it includes
both regulatory testing and on-farm surveillance. As the National Scrapie
Eradication Program moves closer towards meeting the goal of identifying the
last remaining cases of classical scrapie, finding and testing all sheep and
goats meeting targeted sampling criteria is even more important. As of June 30,
2014, 1,174 sheep and 440 goats have been tested on-farm for FY 2014. As of June
30, 15 sheep and 9 goats have tested positive. The number of animals tested
on-farm by month and by species for FY 2014 is shown in Chart 7. Total Animals
Sampled for Scrapie Testing As of June 30, 2014, 33,787 animals have been
sampled for scrapie testing:
•32,173 RSSS samples and 1,614 on-farm samples [includes regulatory testing
(necropsy and live-animal) and on-farm surveillance] (Chart 8);
•Of which 27,582 were sheep and 6,205 were goats. Distribution of sampling
by type (RSSS or on-farm) and by species is shown in Chart 9. http://www.aphis.usda.gov/animal_health/animal_diseases/scrapie/downloads/monthly_scrapie_report.pdf
Overall, all Nor98 isolates contained highly PK resistant PrPres
aggregates, with the main PrPres being a non-glycosylated internal fragment,
cleaved at both the N and C termini, which represent the distinctive biochemical
feature of Nor98. This biochemical signature, unique among animal TSEs, is
reminiscent of PrPres observed in human prion disorders such as GSS and
VPSPr.
snip...
At present the only epidemiological link between animal and human TSEs has
been demonstrated for classical BSE and variant CJD [16], [78], showing for the
first time the zoonotic potential of TSEs. Since then, the implementation of
active surveillance in livestock has led to the identification of Nor98 and
other previously unrecognised animal prion strains, mainly with a sporadic
occurrence, whose origin and zoonotic potential are still poorly understood
[79]. It has been previously shown that peripheral tissues of sheep with Nor98
might harbour detectable levels of infectivity [49], [50], indicating that
infectious material might enter the food chain. On the other hand, the well
known genetic aetiology of GSS suggests that the similar PrPSc conformations
found in Nor98 and GSS P102L are unlikely to indicate a common infectious
source, but might derive from a similar molecular mechanisms involved in
PrPC-to-PrPSc conversion.
snip...
Citation: Pirisinu L, Nonno R, Esposito E, Benestad SL, Gambetti P, et al.
(2013) Small Ruminant Nor98 Prions Share Biochemical Features with Human
Gerstmann-Sträussler-Scheinker Disease and Variably Protease-Sensitive
Prionopathy. PLoS ONE 8(6): e66405. doi:10.1371/journal.pone.0066405
Editor: Corinne Ida Lasmezas, The Scripps Research Institute Scripps
Florida, United States of America
Received: January 24, 2013; Accepted: May 6, 2013; Published: June 24,
2013
Copyright: © 2013 Pirisinu et al. This is an open-access article
distributed under the terms of the Creative Commons Attribution License, which
permits unrestricted use, distribution, and reproduction in any medium, provided
the original author and source are credited.
Funding: This work was supported by grants from the Italian Ministry of
Health (RF-2009-1474624); the European Union (Neuroprion Network of Excellence
CT-2004–506579); the National Institutes of Health (NIH) NS062787, NIH AG-08012,
AG-14359; Alliance BioSecure, as well as the Center for Disease Control and
Prevention Contract UR8/CCU515004. The funders had no role in study design, data
collection and analysis, decision to publish, or preparation of the
manuscript.
Competing interests: The authors have declared that no competing interests
exist.
*** The discovery of previously unrecognized prion diseases in both humans
and animals (i.e., Nor98 in small ruminants) demonstrates that the range of
prion diseases might be wider than expected and raises crucial questions about
the epidemiology and strain properties of these new forms. We are investigating
this latter issue by molecular and biological comparison of VPSPr, GSS and
Nor98.
VARIABLY PROTEASE-SENSITVE PRIONOPATHY IS TRANSMISSIBLE ...price of prion
poker goes up again $
OR-10: Variably protease-sensitive prionopathy is transmissible in bank
voles
Romolo Nonno,1 Michele Di Bari,1 Laura Pirisinu,1 Claudia D’Agostino,1
Stefano Marcon,1 Geraldina Riccardi,1 Gabriele Vaccari,1 Piero Parchi,2 Wenquan
Zou,3 Pierluigi Gambetti,3 Umberto Agrimi1 1Istituto Superiore di Sanità; Rome,
Italy; 2Dipartimento di Scienze Neurologiche, Università di Bologna; Bologna,
Italy; 3Case Western Reserve University; Cleveland, OH USA
Background. Variably protease-sensitive prionopathy (VPSPr) is a recently
described “sporadic”neurodegenerative disease involving prion protein
aggregation, which has clinical similarities with non-Alzheimer dementias, such
as fronto-temporal dementia. Currently, 30 cases of VPSPr have been reported in
Europe and USA, of which 19 cases were homozygous for valine at codon 129 of the
prion protein (VV), 8 were MV and 3 were MM. A distinctive feature of VPSPr is
the electrophoretic pattern of PrPSc after digestion with proteinase K (PK).
After PK-treatment, PrP from VPSPr forms a ladder-like electrophoretic pattern
similar to that described in GSS cases. The clinical and pathological features
of VPSPr raised the question of the correct classification of VPSPr among prion
diseases or other forms of neurodegenerative disorders. Here we report
preliminary data on the transmissibility and pathological features of VPSPr
cases in bank voles.
Materials and Methods. Seven VPSPr cases were inoculated in two genetic
lines of bank voles, carrying either methionine or isoleucine at codon 109 of
the prion protein (named BvM109 and BvI109, respectively). Among the VPSPr cases
selected, 2 were VV at PrP codon 129, 3 were MV and 2 were MM. Clinical
diagnosis in voles was confirmed by brain pathological assessment and western
blot for PK-resistant PrPSc (PrPres) with mAbs SAF32, SAF84, 12B2 and 9A2.
Results. To date, 2 VPSPr cases (1 MV and 1 MM) gave positive transmission
in BvM109. Overall, 3 voles were positive with survival time between 290 and 588
d post inoculation (d.p.i.). All positive voles accumulated PrPres in the form
of the typical PrP27–30, which was indistinguishable to that previously observed
in BvM109 inoculated with sCJDMM1 cases.
In BvI109, 3 VPSPr cases (2 VV and 1 MM) showed positive transmission until
now. Overall, 5 voles were positive with survival time between 281 and 596
d.p.i.. In contrast to what observed in BvM109, all BvI109 showed a GSS-like
PrPSc electrophoretic pattern, characterized by low molecular weight PrPres.
These PrPres fragments were positive with mAb 9A2 and 12B2, while being negative
with SAF32 and SAF84, suggesting that they are cleaved at both the C-terminus
and the N-terminus. Second passages are in progress from these first successful
transmissions.
Conclusions. Preliminary results from transmission studies in bank voles
strongly support the notion that VPSPr is a transmissible prion disease.
Interestingly, VPSPr undergoes divergent evolution in the two genetic lines of
voles, with sCJD-like features in BvM109 and GSS-like properties in BvI109.
The discovery of previously unrecognized prion diseases in both humans and
animals (i.e., Nor98 in small ruminants) demonstrates that the range of prion
diseases might be wider than expected and raises crucial questions about the
epidemiology and strain properties of these new forms. We are investigating this
latter issue by molecular and biological comparison of VPSPr, GSS and Nor98.
Wednesday, March 28, 2012
VARIABLY PROTEASE-SENSITVE PRIONOPATHY IS TRANSMISSIBLE, price of prion
poker goes up again $
Thursday, October 10, 2013
CJD REPORT 1994 increased risk for consumption of veal and venison and lamb
*** The discovery of previously unrecognized prion diseases in both humans
and animals (i.e., Nor98 in small ruminants) demonstrates that the range of
prion diseases might be wider than expected and raises crucial questions about
the epidemiology and strain properties of these new forms. We are investigating
this latter issue by molecular and biological comparison of VPSPr, GSS and
Nor98.
Increased Atypical Scrapie Detections
Press reports indicate that increased surveillance is catching what
otherwise would have been unreported findings of atypical scrapie in sheep. In
2009, five new cases have been reported in Quebec, Ontario, Alberta, and
Saskatchewan. With the exception of Quebec, all cases have been diagnosed as
being the atypical form found in older animals. Canada encourages producers to
join its voluntary surveillance program in order to gain scrapie-free status.
The World Animal Health will not classify Canada as scrapie-free until no new
cases are reported for seven years. The Canadian Sheep Federation is calling on
the government to fund a wider surveillance program in order to establish the
level of prevalence prior to setting an eradication date. Besides long-term
testing, industry is calling for a compensation program for farmers who report
unusual deaths in their flocks.
Thursday, March 29, 2012
atypical Nor-98 Scrapie has spread from coast to coast in the USA 2012
NIAA Annual Conference April 11-14, 2011San Antonio, Texas
Monday, April 25, 2011
Experimental Oral Transmission of Atypical Scrapie to Sheep
Volume 17, Number 5-May 2011 However, work with transgenic mice has
demonstrated the potential susceptibility of pigs, with the disturbing finding
that the biochemical properties of the resulting PrPSc have changed on
transmission (40).
Monday, December 14, 2009
Similarities between Forms of Sheep Scrapie and Creutzfeldt-Jakob Disease
Are Encoded by Distinct Prion Types
(hmmm, this is getting interesting now...TSS)
Sporadic CJD type 1 and atypical/ Nor98 scrapie are characterized by fine
(reticular) deposits,
see also ;
All of the Heidenhain variants were of the methionine/ methionine type 1
molecular subtype.
see full text ;
Monday, December 14, 2009
Similarities between Forms of Sheep Scrapie and Creutzfeldt-Jakob Disease
Are Encoded by Distinct Prion Types
P03.141
Aspects of the Cerebellar Neuropathology in Nor98
Gavier-Widén, D1; Benestad, SL2; Ottander, L1; Westergren, E1 1National
Veterinary Insitute, Sweden; 2National Veterinary Institute,
Norway Nor98 is a prion disease of old sheep and goats. This atypical form
of scrapie was first described in Norway in 1998. Several features of Nor98 were
shown to be different from classical scrapie including the distribution of
disease associated prion protein (PrPd) accumulation in the brain. The
cerebellum is generally the most affected brain area in Nor98. The study here
presented aimed at adding information on the neuropathology in the cerebellum of
Nor98 naturally affected sheep of various genotypes in Sweden and Norway. A
panel of histochemical and immunohistochemical (IHC) stainings such as IHC for
PrPd, synaptophysin, glial fibrillary acidic protein, amyloid, and cell markers
for phagocytic cells were conducted. The type of histological lesions and tissue
reactions were evaluated. The types of PrPd deposition were characterized. The
cerebellar cortex was regularly affected, even though there was a variation in
the severity of the lesions from case to case. Neuropil vacuolation was more
marked in the molecular layer, but affected also the granular cell layer. There
was a loss of granule cells. Punctate deposition of PrPd was characteristic. It
was morphologically and in distribution identical with that of synaptophysin,
suggesting that PrPd accumulates in the synaptic structures. PrPd was also
observed in the granule cell layer and in the white matter. The pathology
features of Nor98 in the cerebellum of the affected sheep showed similarities
with those of sporadic Creutzfeldt-Jakob disease in humans.
***The pathology features of Nor98 in the cerebellum of the affected sheep
showed similarities with those of sporadic Creutzfeldt-Jakob disease in
humans.
PR-26
NOR98 SHOWS MOLECULAR FEATURES REMINISCENT OF GSS
R. Nonno1, E. Esposito1, G. Vaccari1, E. Bandino2, M. Conte1, B.
Chiappini1, S. Marcon1, M. Di Bari1, S.L. Benestad3, U. Agrimi1 1 Istituto
Superiore di Sanità, Department of Food Safety and Veterinary Public Health,
Rome, Italy (romolo.nonno@iss.it); 2 Istituto Zooprofilattico della Sardegna,
Sassari, Italy; 3 National Veterinary Institute, Department of Pathology, Oslo,
Norway
Molecular variants of PrPSc are being increasingly investigated in sheep
scrapie and are generally referred to as "atypical" scrapie, as opposed to
"classical scrapie". Among the atypical group, Nor98 seems to be the best
identified. We studied the molecular properties of Italian and Norwegian Nor98
samples by WB analysis of brain homogenates, either untreated, digested with
different concentrations of proteinase K, or subjected to enzymatic
deglycosylation. The identity of PrP fragments was inferred by means of
antibodies spanning the full PrP sequence. We found that undigested brain
homogenates contain a Nor98-specific PrP fragment migrating at 11 kDa (PrP11),
truncated at both the C-terminus and the N-terminus, and not N-glycosylated.
After mild PK digestion, Nor98 displayed full-length PrP (FL-PrP) and
N-glycosylated C-terminal fragments (CTF), along with increased levels of PrP11.
Proteinase K digestion curves (0,006-6,4 mg/ml) showed that FL-PrP and CTF are
mainly digested above 0,01 mg/ml, while PrP11 is not entirely digested even at
the highest concentrations, similarly to PrP27-30 associated with classical
scrapie. Above 0,2 mg/ml PK, most Nor98 samples showed only PrP11 and a fragment
of 17 kDa with the same properties of PrP11, that was tentatively identified as
a dimer of PrP11. Detergent solubility studies showed that PrP11 is insoluble in
2% sodium laurylsorcosine and is mainly produced from detergentsoluble,
full-length PrPSc. Furthermore, among Italian scrapie isolates, we found that a
sample with molecular and pathological properties consistent with Nor98 showed
plaque-like deposits of PrPSc in the thalamus when the brain was analysed by
PrPSc immunohistochemistry. Taken together, our results show that the
distinctive pathological feature of Nor98 is a PrP fragment spanning amino acids
~ 90-155. This fragment is produced by successive N-terminal and C-terminal
cleavages from a full-length and largely detergent-soluble PrPSc, is produced in
vivo and is extremely resistant to PK digestion.
*** Intriguingly, these conclusions suggest that some pathological features
of Nor98 are reminiscent of Gerstmann-Sträussler-Scheinker disease.
119
A newly identified type of scrapie agent can naturally infect sheep with
resistant PrP genotypes
Annick Le Dur*,?, Vincent Béringue*,?, Olivier Andréoletti?, Fabienne
Reine*, Thanh Lan Laï*, Thierry Baron§, Bjørn Bratberg¶, Jean-Luc Vilotte?,
Pierre Sarradin**, Sylvie L. Benestad¶, and Hubert Laude*,?? +Author
Affiliations
*Virologie Immunologie Moléculaires and ?Génétique Biochimique et
Cytogénétique, Institut National de la Recherche Agronomique, 78350
Jouy-en-Josas, France; ?Unité Mixte de Recherche, Institut National de la
Recherche Agronomique-Ecole Nationale Vétérinaire de Toulouse, Interactions Hôte
Agent Pathogène, 31066 Toulouse, France; §Agence Française de Sécurité Sanitaire
des Aliments, Unité Agents Transmissibles Non Conventionnels, 69364 Lyon,
France; **Pathologie Infectieuse et Immunologie, Institut National de la
Recherche Agronomique, 37380 Nouzilly, France; and ¶Department of Pathology,
National Veterinary Institute, 0033 Oslo, Norway
***Edited by Stanley B. Prusiner, University of California, San Francisco,
CA (received for review March 21, 2005)
Abstract Scrapie in small ruminants belongs to transmissible spongiform
encephalopathies (TSEs), or prion diseases, a family of fatal neurodegenerative
disorders that affect humans and animals and can transmit within and between
species by ingestion or inoculation. Conversion of the host-encoded prion
protein (PrP), normal cellular PrP (PrPc), into a misfolded form, abnormal PrP
(PrPSc), plays a key role in TSE transmission and pathogenesis. The intensified
surveillance of scrapie in the European Union, together with the improvement of
PrPSc detection techniques, has led to the discovery of a growing number of
so-called atypical scrapie cases. These include clinical Nor98 cases first
identified in Norwegian sheep on the basis of unusual pathological and PrPSc
molecular features and "cases" that produced discordant responses in the rapid
tests currently applied to the large-scale random screening of slaughtered or
fallen animals. Worryingly, a substantial proportion of such cases involved
sheep with PrP genotypes known until now to confer natural resistance to
conventional scrapie. Here we report that both Nor98 and discordant cases,
including three sheep homozygous for the resistant PrPARR allele (A136R154R171),
efficiently transmitted the disease to transgenic mice expressing ovine PrP, and
that they shared unique biological and biochemical features upon propagation in
mice. *** These observations support the view that a truly infectious TSE agent,
unrecognized until recently, infects sheep and goat flocks and may have
important implications in terms of scrapie control and public health.
Monday, December 1, 2008
When Atypical Scrapie cross species barriers
Authors
Andreoletti O., Herva M. H., Cassard H., Espinosa J. C., Lacroux C., Simon
S., Padilla D., Benestad S. L., Lantier F., Schelcher F., Grassi J., Torres, J.
M., UMR INRA ENVT 1225, Ecole Nationale Veterinaire de Toulouse.France;
ICISA-INlA, Madrid, Spain; CEA, IBiTec-5, DSV, CEA/Saclay, Gif sur Yvette cedex,
France; National Veterinary Institute, Postboks 750 Sentrum, 0106 Oslo, Norway,
INRA IASP, Centre INRA de Tours, 3738O Nouzilly, France.
Content
Atypical scrapie is a TSE occurring in small ruminants and harbouring
peculiar clinical, epidemiological and biochemical properties. Currently this
form of disease is identified in a large number of countries. In this study we
report the transmission of an atypical scrapie isolate through different species
barriers as modeled by transgenic mice (Tg) expressing different species PRP
sequence.
The donor isolate was collected in 1995 in a French commercial sheep flock.
inoculation into AHQ/AHQ sheep induced a disease which had all
neuro-pathological and biochemical characteristics of atypical scrapie.
Transmitted into Transgenic mice expressing either ovine or PrPc, the isolate
retained all the described characteristics of atypical scrapie.
Surprisingly the TSE agent characteristics were dramatically different
v/hen passaged into Tg bovine mice. The recovered TSE agent had biological and
biochemical characteristics similar to those of atypical BSE L in the same mouse
model. Moreover, whereas no other TSE agent than BSE were shown to transmit into
Tg porcine mice, atypical scrapie was able to develop into this model, albeit
with low attack rate on first passage.
Furthermore, after adaptation in the porcine mouse model this prion showed
similar biological and biochemical characteristics than BSE adapted to this
porcine mouse model. Altogether these data indicate.
(i) the unsuspected potential abilities of atypical scrapie to cross
species barriers
(ii) the possible capacity of this agent to acquire new characteristics
when crossing species barrier
These findings raise some interrogation on the concept of TSE strain and on
the origin of the diversity of the TSE agents and could have consequences on
field TSE control measures.
Friday, February 11, 2011
Atypical/Nor98 Scrapie Infectivity in Sheep Peripheral Tissues
Saturday, August 14, 2010
BSE Case Associated with Prion Protein Gene Mutation (g-h-BSEalabama) and
VPSPr PRIONPATHY
(see mad cow feed in COMMERCE IN ALABAMA...TSS)
why do we not want to do TSE transmission studies on chimpanzees $
5. A positive result from a chimpanzee challenged severly would likely
create alarm in some circles even if the result could not be interpreted for
man. I have a view that all these agents could be transmitted provided a large
enough dose by appropriate routes was given and the animals kept long enough.
Until the mechanisms of the species barrier are more clearly understood it might
be best to retain that hypothesis.
snip...
R. BRADLEY
1: J Infect Dis 1980 Aug;142(2):205-8
Oral transmission of kuru, Creutzfeldt-Jakob disease, and scrapie to
nonhuman primates.
Gibbs CJ Jr, Amyx HL, Bacote A, Masters CL, Gajdusek DC.
Kuru and Creutzfeldt-Jakob disease of humans and scrapie disease of sheep
and goats were transmitted to squirrel monkeys (Saimiri sciureus) that were
exposed to the infectious agents only by their nonforced consumption of known
infectious tissues. The asymptomatic incubation period in the one monkey exposed
to the virus of kuru was 36 months; that in the two monkeys exposed to the virus
of Creutzfeldt-Jakob disease was 23 and 27 months, respectively; and that in the
two monkeys exposed to the virus of scrapie was 25 and 32 months, respectively.
Careful physical examination of the buccal cavities of all of the monkeys failed
to reveal signs or oral lesions. One additional monkey similarly exposed to kuru
has remained asymptomatic during the 39 months that it has been under
observation.
snip...
The successful transmission of kuru, Creutzfeldt-Jakob disease, and scrapie
by natural feeding to squirrel monkeys that we have reported provides further
grounds for concern that scrapie-infected meat may occasionally give rise in
humans to Creutzfeldt-Jakob disease.
PMID: 6997404
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=6997404&dopt=Abstract
Recently the question has again been brought up as to whether scrapie is
transmissible to man. This has followed reports that the disease has been
transmitted to primates. One particularly lurid speculation (Gajdusek 1977)
conjectures that the agents of scrapie, kuru, Creutzfeldt-Jakob disease and
transmissible encephalopathy of mink are varieties of a single "virus". The U.S.
Department of Agriculture concluded that it could "no longer justify or permit
scrapie-blood line and scrapie-exposed sheep and goats to be processed for human
or animal food at slaughter or rendering plants" (ARC 84/77)" The problem is
emphasised by the finding that some strains of scrapie produce lesions identical
to the once which characterise the human dementias"
Whether true or not. the hypothesis that these agents might be
transmissible to man raises two considerations. First, the safety of laboratory
personnel requires prompt attention. Second, action such as the "scorched meat"
policy of USDA makes the solution of the acrapie problem urgent if the sheep
industry is not to suffer grievously.
snip...
76/10.12/4.6
Nature. 1972 Mar 10;236(5341):73-4.
Transmission of scrapie to the cynomolgus monkey (Macaca fascicularis).
Gibbs CJ Jr, Gajdusek DC.
Nature 236, 73 - 74 (10 March 1972); doi:10.1038/236073a0
Transmission of Scrapie to the Cynomolgus Monkey (Macaca fascicularis)
C. J. GIBBS jun. & D. C. GAJDUSEK
National Institute of Neurological Diseases and Stroke, National Institutes
of Health, Bethesda, Maryland
SCRAPIE has been transmitted to the cynomolgus, or crab-eating, monkey
(Macaca fascicularis) with an incubation period of more than 5 yr from the time
of intracerebral inoculation of scrapie-infected mouse brain. The animal
developed a chronic central nervous system degeneration, with ataxia, tremor and
myoclonus with associated severe scrapie-like pathology of intensive astroglial
hypertrophy and proliferation, neuronal vacuolation and status spongiosus of
grey matter. The strain of scrapie virus used was the eighth passage in Swiss
mice (NIH) of a Compton strain of scrapie obtained as ninth intracerebral
passage of the agent in goat brain, from Dr R. L. Chandler (ARC, Compton,
Berkshire).
Suspect symptoms
What if you can catch old-fashioned CJD by eating meat from a sheep
infected with scrapie?
28 Mar 01
Like lambs to the slaughter 31 March 2001 by Debora MacKenzie Magazine
issue 2284. Subscribe and get 4 free issues. FOUR years ago, Terry Singeltary
watched his mother die horribly from a degenerative brain disease. Doctors told
him it was Alzheimer's, but Singeltary was suspicious. The diagnosis didn't fit
her violent symptoms, and he demanded an autopsy. It showed she had died of
sporadic Creutzfeldt-Jakob disease.
Most doctors believe that sCJD is caused by a prion protein deforming by
chance into a killer. But Singeltary thinks otherwise. He is one of a number of
campaigners who say that some sCJD, like the variant CJD related to BSE, is
caused by eating meat from infected animals. Their suspicions have focused on
sheep carrying scrapie, a BSE-like disease that is widespread in flocks across
Europe and North America.
Now scientists in France have stumbled across new evidence that adds weight
to the campaigners' fears. To their complete surprise, the researchers found
that one strain of scrapie causes the same brain damage in mice as sCJD.
"This means we cannot rule out that at least some sCJD may be caused by
some strains of scrapie," says team member Jean-Philippe Deslys of the French
Atomic Energy Commission's medical research laboratory in Fontenay-aux-Roses,
south-west of Paris. Hans Kretschmar of the University of Göttingen, who
coordinates CJD surveillance in Germany, is so concerned by the findings that he
now wants to trawl back through past sCJD cases to see if any might have been
caused by eating infected mutton or lamb.
Scrapie has been around for centuries and until now there has been no
evidence that it poses a risk to human health. But if the French finding means
that scrapie can cause sCJD in people, countries around the world may have
overlooked a CJD crisis to rival that caused by BSE.
Deslys and colleagues were originally studying vCJD, not sCJD. They
injected the brains of macaque monkeys with brain from BSE cattle, and from
French and British vCJD patients. The brain damage and clinical symptoms in the
monkeys were the same for all three. Mice injected with the original sets of
brain tissue or with infected monkey brain also developed the same
symptoms.
As a control experiment, the team also injected mice with brain tissue from
people and animals with other prion diseases: a French case of sCJD; a French
patient who caught sCJD from human-derived growth hormone; sheep with a French
strain of scrapie; and mice carrying a prion derived from an American scrapie
strain. As expected, they all affected the brain in a different way from BSE and
vCJD. But while the American strain of scrapie caused different damage from
sCJD, the French strain produced exactly the same pathology.
"The main evidence that scrapie does not affect humans has been
epidemiology," says Moira Bruce of the neuropathogenesis unit of the Institute
for Animal Health in Edinburgh, who was a member of the same team as Deslys.
"You see about the same incidence of the disease everywhere, whether or not
there are many sheep, and in countries such as New Zealand with no scrapie." In
the only previous comparisons of sCJD and scrapie in mice, Bruce found they were
dissimilar.
But there are more than 20 strains of scrapie, and six of sCJD. "You would
not necessarily see a relationship between the two with epidemiology if only
some strains affect only some people," says Deslys. Bruce is cautious about the
mouse results, but agrees they require further investigation. Other trials of
scrapie and sCJD in mice, she says, are in progress.
People can have three different genetic variations of the human prion
protein, and each type of protein can fold up two different ways. Kretschmar has
found that these six combinations correspond to six clinical types of sCJD: each
type of normal prion produces a particular pathology when it spontaneously
deforms to produce sCJD.
But if these proteins deform because of infection with a disease-causing
prion, the relationship between pathology and prion type should be different, as
it is in vCJD. "If we look at brain samples from sporadic CJD cases and find
some that do not fit the pattern," says Kretschmar, "that could mean they were
caused by infection."
There are 250 deaths per year from sCJD in the US, and a similar incidence
elsewhere. Singeltary and other US activists think that some of these people
died after eating contaminated meat or "nutritional" pills containing dried
animal brain. Governments will have a hard time facing activists like Singeltary
if it turns out that some sCJD isn't as spontaneous as doctors have
insisted.
Deslys's work on macaques also provides further proof that the human
disease vCJD is caused by BSE. And the experiments showed that vCJD is much more
virulent to primates than BSE, even when injected into the bloodstream rather
than the brain. This, says Deslys, means that there is an even bigger risk than
we thought that vCJD can be passed from one patient to another through
contaminated blood transfusions and surgical instruments.
Sunday, December 12, 2010
EFSA reviews BSE/TSE infectivity in small ruminant tissues News Story 2
December 2010
Wednesday, January 18, 2012
Selection of Distinct Strain Phenotypes in Mice Infected by Ovine Natural
Scrapie Isolates Similar to CH1641 Experimental Scrapie
Journal of Neuropathology & Experimental Neurology: February 2012 -
Volume 71 - Issue 2 - p 140–147
Thursday, July 14, 2011
Histopathological Studies of "CH1641-Like" Scrapie Sources Versus Classical
Scrapie and BSE Transmitted to Ovine Transgenic Mice (TgOvPrP4)
Wednesday, January 18, 2012
BSE IN GOATS CAN BE MISTAKEN FOR SCRAPIE
February 1, 2012
Thursday, December 23, 2010
Molecular Typing of Protease-Resistant Prion Protein in Transmissible
Spongiform Encephalopathies of Small Ruminants, France, 2002-2009
Volume 17, Number 1 January 2011
Thursday, November 18, 2010
Increased susceptibility of human-PrP transgenic mice to bovine spongiform
encephalopathy following passage in sheep
Monday, December 14, 2009
Similarities between Forms of Sheep Scrapie and Creutzfeldt-Jakob Disease
Are Encoded by Distinct Prion Types
(hmmm, this is getting interesting now...TSS)
Sporadic CJD type 1 and atypical/ Nor98 scrapie are characterized by fine
(reticular) deposits,
see also ;
All of the Heidenhain variants were of the methionine/ methionine type 1
molecular subtype.
see full text ;
Monday, December 14, 2009
Similarities between Forms of Sheep Scrapie and Creutzfeldt-Jakob Disease
Are Encoded by Distinct Prion Types
Thursday, July 21, 2011
A Second Case of Gerstmann-Sträussler-Scheinker Disease Linked to the G131V
Mutation in the Prion Protein Gene in a Dutch Patient Journal of Neuropathology
& Experimental Neurology:
August 2011 - Volume 70 - Issue 8 - pp 698-702
Monday, April 25, 2011
Experimental Oral Transmission of Atypical Scrapie to Sheep
Volume 17, Number 5-May 2011
Sunday, April 18, 2010
SCRAPIE AND ATYPICAL SCRAPIE TRANSMISSION STUDIES A REVIEW 2010
Thursday, November 18, 2010
Increased susceptibility of human-PrP transgenic mice to bovine spongiform
encephalopathy following passage in sheep
Wednesday, January 19, 2011
EFSA and ECDC review scientific evidence on possible links between TSEs in
animals and humans Webnachricht 19 Januar 2011
Monday, June 27, 2011
Comparison of Sheep Nor98 with Human Variably Protease-Sensitive
Prionopathy and Gerstmann-Sträussler-Scheinker Disease
Thursday, November 18, 2010
Increased susceptibility of human-PrP transgenic mice to bovine spongiform
encephalopathy following passage in sheep
Wednesday, November 13, 2013
Atypical Scrapie Prions from Sheep and Lack of Disease in Transgenic Mice
Overexpressing Human Prion Protein
PRION 2014 CONFERENCE
CHRONIC WASTING DISEASE CWD
A FEW FINDINGS ;
Conclusions. To our knowledge, this is the first established experimental
model of CWD in TgSB3985. We found evidence for co-existence or divergence of
two CWD strains adapted to Tga20 mice and their replication in TgSB3985 mice.
Finally, we observed phenotypic differences between cervid-derived CWD and
CWD/Tg20 strains upon propagation in TgSB3985 mice. Further studies are underway
to characterize these strains.
We conclude that TSE infectivity is likely to survive burial for long time
periods with minimal loss of infectivity and limited movement from the original
burial site. However PMCA results have shown that there is the potential for
rainwater to elute TSE related material from soil which could lead to the
contamination of a wider area. These experiments reinforce the importance of
risk assessment when disposing of TSE risk materials.
The results show that even highly diluted PrPSc can bind efficiently to
polypropylene, stainless steel, glass, wood and stone and propagate the
conversion of normal prion protein. For in vivo experiments, hamsters were ic
injected with implants incubated in 1% 263K-infected brain homogenate. Hamsters,
inoculated with 263K-contaminated implants of all groups, developed typical
signs of prion disease, whereas control animals inoculated with non-contaminated
materials did not.
Our data establish that meadow voles are permissive to CWD via peripheral
exposure route, suggesting they could serve as an environmental reservoir for
CWD. Additionally, our data are consistent with the hypothesis that at least two
strains of CWD circulate in naturally-infected cervid populations and provide
evidence that meadow voles are a useful tool for CWD strain typing.
Conclusion. CWD prions are shed in saliva and urine of infected deer as
early as 3 months post infection and throughout the subsequent >1.5 year
course of infection. In current work we are examining the relationship of
prionemia to excretion and the impact of excreted prion binding to surfaces and
particulates in the environment.
Conclusion. CWD prions (as inferred by prion seeding activity by RT-QuIC)
are shed in urine of infected deer as early as 6 months post inoculation and
throughout the subsequent disease course. Further studies are in progress
refining the real-time urinary prion assay sensitivity and we are examining more
closely the excretion time frame, magnitude, and sample variables in
relationship to inoculation route and prionemia in naturally and experimentally
CWD-infected cervids.
Conclusions. Our results suggested that the odds of infection for CWD is
likely controlled by areas that congregate deer thus increasing direct
transmission (deer-to-deer interactions) or indirect transmission
(deer-to-environment) by sharing or depositing infectious prion proteins in
these preferred habitats. Epidemiology of CWD in the eastern U.S. is likely
controlled by separate factors than found in the Midwestern and endemic areas
for CWD and can assist in performing more efficient surveillance efforts for the
region.
Conclusions. During the pre-symptomatic stage of CWD infection and
throughout the course of disease deer may be shedding multiple LD50 doses per
day in their saliva. CWD prion shedding through saliva and excreta may account
for the unprecedented spread of this prion disease in nature.
see full text and more ;
Monday, June 23, 2014
*** PRION 2014 CHRONIC WASTING DISEASE CWD
Thursday, July 03, 2014
*** How Chronic Wasting Disease is affecting deer population and what’s the
risk to humans and pets?
Tuesday, July 01, 2014
*** CHRONIC WASTING DISEASE CWD TSE PRION DISEASE, GAME FARMS, AND
POTENTIAL RISK FACTORS THERE FROM
Sunday, July 13, 2014
Louisiana deer mystery unleashes litigation 6 does still missing from CWD
index herd in Pennsylvania Great Escape
Monday, July 28, 2014
*** Mitigating the Risk of Transmission and Environmental Contamination of
Transmissible Spongiform Encephalopathies 2013 Annual Report
Transmissible Spongiform Encephalopathy TSE Prion Disease North America
2014
Transmissible Spongiform Encephalopathy TSE Prion Disease have now been
discovered in a wide verity of species across North America. typical C-BSE,
atypical L-type BASE BSE, atypical H-type BSE, atypical H-G BSE, of the bovine,
typical and atypical Scrapie strains, in sheep and goats, with atypical Nor-98
Scrapie spreading coast to coast in about 5 years. Chronic Wasting Disease CWD
in cervid is slowly spreading without any stopping it in Canada and the USA and
now has mutated into many different strains. Transmissible Mink Encephalopathy
TME outbreaks. These Transmissible Spongiform Encephalopathy TSE Prion Disease
have been silently mutating and spreading in different species in North America
for decades.
The USDA, FDA, et al have assured us of a robust Triple BSE TSE prion
Firewall, of which we now know without a doubt, that it was nothing but ink on
paper. Since the 1997 mad cow feed ban in the USA, literally tons and tons of
banned mad cow feed has been put out into commerce, never to return, as late as
December of 2013, serious, serious breaches in the FDA mad cow feed ban have
been documented. The 2004 enhanced BSE surveillance program was so flawed, that
one of the top TSE prion Scientist for the CDC, Dr. Paul Brown stated ; Brown,
who is preparing a scientific paper based on the latest two mad cow cases to
estimate the maximum number of infected cows that occurred in the United States,
said he has "absolutely no confidence in USDA tests before one year ago" because
of the agency's reluctance to retest the Texas cow that initially tested
positive. see ; http://www.upi.com/Health_News/2006/03/15/Analysis-What-that-mad-cow-means/UPI-12841142465253/
The BSE surveillance and testing have also been proven to be flawed, and
the GAO and OIG have both raised serious question as to just how flawed it has
been (see GAO and OIG reports). North America has more documented TSE prion
disease, in different documented species (excluding the Zoo BSE animals in the
EU), then any other place on the Globe. This does not include the very
likelihood that TSE prion disease in the domestic feline and canine have been
exposed to high doses of the TSE prion disease vid pet food. To date, it’s still
legal to include deer from cwd zone into pet food or deer food. Specified Risk
Material i.e. SRM bans still being breach, as recently as just last month.
nvCJD or what they now call vCJD, another case documented in Texas last
month, with very little information being released to the public on about this
case? with still the same line of thought from federal officials, ‘it can’t
happen here’, so another vCJD blamed on travel of a foreign animal disease from
another country, while ignoring all the BSE TSE Prion risk factors we have here
in the USA and Canada, and the time that this victim and others, do spend in the
USA, and exposed to these risk factors, apparently do not count in any way with
regard to risk factor. a flawed process of risk assessment.
sporadic CJD, along with new TSE prion disease in humans, of which the
young are dying, of which long duration of illness from onset of symptoms to
death have been documented, only to have a new name added to the pot of prion
disease i.e. sporadic GSS, sporadic FFI, and or VPSPR. I only ponder how a
familial type disease could be sporadic with no genetic link to any family
member? when the USA is the only documented Country in the world to have
documented two different cases of atypical H-type BSE, with one case being
called atypical H-G BSE with the G meaning Genetic, with new science now showing
that indeed atypical H-type BSE is very possible transmitted to cattle via oral
transmission (Prion2014). sporadic CJD and VPSPR have been rising in Canada,
USA, and the UK, with the same old excuse, better surveillance. You can only use
that excuse for so many years, for so many decades, until one must conclude that
CJD TSE prion cases are rising. a 48% incease in CJD in Canada is not just a
blip or a reason of better surveillance, it is a mathematical rise in numbers.
More and more we are seeing more humans exposed in various circumstance in the
Hospital, Medical, Surgical arenas to the TSE Prion disease, and at the same
time in North America, more and more humans are becoming exposed to the TSE
prion disease via consumption of the TSE prion via deer and elk, cattle, sheep
and goats, and for those that are exposed via or consumption, go on to further
expose many others via the iatrogenic modes of transmission of the TSE prion
disease i.e. friendly fire. I pondered this mode of transmission via the victims
of sporadic FFI, sporadic GSS, could this be a iatrogenic event from someone
sub-clinical with sFFI or sGSS ? what if?
Two decades have passed since Dr. Ironside first confirmed his first ten
nvCJD victims in 1995. Ten years later, 2005, we had Dr. Gambetti and his first
ten i.e. VPSPR in younger victims. now we know that indeed VPSPR is
transmissible. yet all these TSE prion disease and victims in the USA and Canada
are being pawned off as a spontaneous event, yet science has shown, the
spontaneous theory has never been proven in any natural case of TSE prion
disease, and scientist have warned, that they have now linked some sporadic CJD
cases to atypical BSE, to atypical Scrapie, and to CWD, yet we don’t here about
this in the public domain. We must make all human and animal TSE prion disease
reportable in every age group, in ever state and internationally, we must have a
serious re-evaluation and testing of the USA cattle herds, and we must ban
interstate movement of all cervids. Any voluntary effort to do any of this will
fail. Folks, we have let the industry run science far too long with regards to
the TSE prion disease. While the industry and their lobbyist continues to funnel
junk science to our decision policy makers, Rome burns. ...end
REFERENCES
Sunday, June 29, 2014
Transmissible Spongiform Encephalopathy TSE Prion Disease North America
2014
TSS
