Rare report of deer disease in Texas causes stir
Rare report of deer disease in Texas causes stir, especially since it’s the
8 case of CWD documented in Texas, and the first case of CWD in Captive deer.
here is how I would have titled this article, and why.
Shannon Tompkins Finally Breaks Silence on Texas First Captive CWD Case and
Starts Off Spreading False Information About Risk Factors. ...
Houston Chronicle
Rare report of deer disease in Texas causes stir
Experts' opinions vary on danger chronic wasting disease poses to herd By
Shannon Tompkins | July 15, 2015 | Updated: July 15, 2015 11:49pm
Emaciated, drooling and listless, a Colorado deer shows signs of chronic
wasting disease, a contagious, invariably fatal malady. Texas officials face
hard decisions on how to address the discovery of the first CWD-positive
whitetail discovered in the state. Photo: HO / COLORADO DIVISION WILDLIFE Photo:
HO
Discovery this past month that a 2-year-old white-tailed deer born and held
in a captive deer breeding/production business in Medina County had tested
positive for chronic wasting disease - the first CWD-positive whitetail
documented in Texas - has state wildlife and domestic livestock health agencies
intently developing and implementing a plan designed to discover the source of
the infection and minimize risk that the contagious, invariably fatal malady
will spread to the state's wild and captive whitetail herds.
At risk, state officials and many wildlife disease specialists say, is the
health of the state's 3.9 million free-ranging white-tailed deer, the
$2.1-billion-a-year deer hunting industry in Texas, and the approximately
110,000 deer held in 1,300 captive breeding/production operations across the
state, generating another $650 million a year in economic value.
But details of the plan developed by Texas Animal Health Commission and
Texas Parks and Wildlife Department, which include protocols calling for the
killing of more than 200 deer on the Medina County property as well as
potentially scores of the more than 700 deer the business sold to other
captive-deer operations over the past five years, have ignited long-smoldering
acrimony from the captive-deer industry and supporters questioning the disease's
effects on deer herds, tactics used by state and federal agencies to prevent its
spread, and even the nature of the disease.
The state's actions in the wake of the discovery of the CWD-positive buck
in the heart of Texas' Edwards Plateau, location of the highest concentration of
captive-deer breeding operations and home to the state's highest number of
free-ranging whitetails, include a temporary statewide prohibition on
transferring or releasing captive deer, negatively affecting all captive-deer
operations. The prohibition is in place, state officials said, until they can
trace the location of any deer that may be the source that infected the Medina
County deer.
Conflicting reports
Texas officials have final control over captive-held whitetails in the
state. Although the state allows private individuals who meet state permitting
rules to hold and even sell captive whitetails, the animals are, under state
law, under control of the state and not property of the permit holder.
The captive-deer industry almost universally sees CWD as a relatively minor
problem used as a cudgel by those who oppose the "deer farming"
businesses.
Others see the disease as a very significant threat to the health of deer
herds, with the potential to erode interest in deer hunting, the economic engine
that supports a multibillion-dollar industry serving Texas' 700,000 deer hunters
and funds wildlife management efforts benefiting all wildlife.
Both sides of the issue were represented Monday at a quickly called hearing
before the Texas House of Representatives Committee on Culture, Recreation and
Tourism. Chronic wasting disease was the sole topic of the four-hour
hearing.
"CWD is a pervasive disease but fairly benign," said Dr. Greg Stewart,
whose position as president of Georgia-based Southern Veterinary Services has
included extensive work with captive deer breeding/production businesses in
Texas and other states. "It's not that big a deal."
Other experts saw the disease very differently.
"Once CWD is established, it is impossible to eradicate," said Dr. Walter
Cook, clinical associate professor at Texas A&M School of Veterinary
Medicine.
When the disease is first discovered in a state's deer herd, "it's no
reason to panic, but it needs a robust response. I feel any (deer) that has
contacted the diseased (deer) should be destroyed," said Cook, who worked for
decades in Wyoming, where CWD infection rates of bucks in one deer herd
approached 50 percent and were cited as a factor in the herd's population
falling by half.
Not a threat to humans
Chronic wasting disease is one of a small group of neurological diseases
called transmissible spongiform encephalopathy. It is similar to two other
animal diseases: bovine spongiform encephalopathy (also called mad cow disease)
and scrapie, a disease affecting sheep. Unlike mad cow disease, CWD is not
considered a threat to human health.
CWD's origin remains subject to debate, but the most commonly accepted
theory is that it is a mutation of the infectious agent causing scrapie and
arose in Colorado during the 1960s, when scrapie jumped the species barrier and
infected wild mule deer.
The infectious agent is a mutated prion, a short chain of amino acids. When
ingested, mutated prions spread, multiply and concentrate in lymphatic and
neural tissue, where they trigger deterioration of the cells. The disease is
untreatable and irreversible, leading to emaciation, loss of body control, and
eventual death.
CWD's effects are progressive and can take years to prove fatal. All the
while, even before showing clinical signs of the disease, an infected animal is
shedding infectious prions through feces, urine and other bodily fluids. Other
deer can become infected through contact with these fluids or even through
eating vegetation that has incorporated the microscopic prions from soil.
The shed prions are extremely hardy, remaining infectious for more than a
decade.
CWD has been found in 23 states and two Canadian provinces. As it has
spread, many states, including Texas, imposed prohibitions on transporting live
deer from outside states and started CWD monitoring programs on free-ranging and
captive deer.
Monitoring programs generally involve removing the brain stem of a dead
deer and examining it for evidence of the disease. There is a live test for CWD;
a deer must be caught and restrained while a biopsy of rectal tissue holding
lymphatic follicles is removed. For the rectal biopsy to be nearly 100 percent
reliable, multiple biopsies must be taken over several months.
Because of the long period it takes to obtain reliable results from the
live tests and urgency of tracing potential sources of infection, Texas uses the
brain stem tests that require the animal to be killed but produce quick,
reliable diagnoses. In a handful of previous instances, when captive-deer
operations have been found illegally importing potentially infected deer, Texas
has depopulated the sites, killing every deer.
Employing that grim protocol for deer in the Medina County situation, in
which the permit holder has followed all state rules but still faces losing
every deer on the property, is not popular with anyone. But it is particularly
irksome for the captive-deer industry.
At Monday's hearing, Rep. Lyle Larson, R-San Antonio, called the action "a
draconian approach" and urged TPWD and TAHC officials to consider using live
tests or other options that would not involve killing scores of deer.
A CWD task force, involving TPWD and TAHC, is expected to decide on how it
will proceed within the next week.
Shannon Tompkins Finally Breaks Silence on Texas First Captive CWD Case
and Starts Off Spreading False Information About Risk Factors. Mr. Tompkins and
the Houston Chronicle have been catering to the captive shooting pen industry
for years. Mr. Tompkins use to write about CWD regularly, but since CWD has been
discovered in Texas, Mr. Tompkins Sir, your silence, and the Houston Chronicle’s
silence, have been deafening. I have been pleading with you both to write
something, but was I was hoping for, was more of a truthful writing of the
scientific facts, and this did not happen. I really am writing this with great
despair, because of the respect I have for the Houston Chronicle, Shannon
Tomkins, TPWD, and the TAHC (well, maybe not so much with the TAHC, after their
blunder with BSE aka mad cow disease in Texas). I kindly wish to submit the
following updated science on CWD TSE Prion.
Shannon Tompkins insistently writes ;
>>>Not a threat to humans<<<
this is completely and absolutely wrong. fact is, scientist have no
absolute clue yet, but science is showing that the risk of humans contracting
CWD is very real, and the science is showing it’s very likely, if it has not
happened already. just look at the recent science coming out of the PRION2015
conference in Ft. Collins, and then you tell me there is no risk of cwd to
humans. ...
*** LATE-BREAKING ABSTRACTS PRION 2015 CONFERENCE ***
O18
Zoonotic Potential of CWD Prions
Liuting Qing1, Ignazio Cali1,2, Jue Yuan1, Shenghai Huang3, Diane Kofskey1,
Pierluigi Gambetti1, Wenquan Zou1, Qingzhong Kong1 1Case Western Reserve
University, Cleveland, Ohio, USA, 2Second University of Naples, Naples, Italy,
3Encore Health Resources, Houston, Texas, USA
Chronic wasting disease (CWD) is a widespread and expanding prion disease
in free-ranging and captive cervid species in North America. The zoonotic
potential of CWD prions is a serious public health concern. Current literature
generated with in vitro methods and in vivo animal models (transgenic mice,
macaques and squirrel monkeys) reports conflicting results. The susceptibility
of human CNS and peripheral organs to CWD prions remains largely unresolved. In
our earlier bioassay experiments using several humanized transgenic mouse lines,
we detected protease-resistant PrPSc in the spleen of two out of 140 mice that
were intracerebrally inoculated with natural CWD isolates, but PrPSc was not
detected in the brain of the same mice. Secondary passages with such
PrPSc-positive CWD-inoculated humanized mouse spleen tissues led to efficient
prion transmission with clear clinical and pathological signs in both humanized
and cervidized transgenic mice. Furthermore, a recent bioassay with natural CWD
isolates in a new humanized transgenic mouse line led to clinical prion
infection in 2 out of 20 mice. These results indicate that the CWD prion has the
potential to infect human CNS and peripheral lymphoid tissues and that there
might be asymptomatic human carriers of CWD infection.
==================
***These results indicate that the CWD prion has the potential to infect
human CNS and peripheral lymphoid tissues and that there might be asymptomatic
human carriers of CWD infection.***
==================
P.105: RT-QuIC models trans-species prion transmission
Kristen Davenport, Davin Henderson, Candace Mathiason, and Edward Hoover
Prion Research Center; Colorado State University; Fort Collins, CO USA
The propensity for trans-species prion transmission is related to the
structural characteristics of the enciphering and heterologous PrP, but the
exact mechanism remains mostly mysterious. Studies of the effects of primary or
tertiary prion protein structures on trans-species prion transmission have
relied primarily upon animal bioassays, making the influence of prion protein
structure vs. host co-factors (e.g. cellular constituents, trafficking, and
innate immune interactions) difficult to dissect. As an alternative strategy, we
used real-time quakinginduced conversion (RT-QuIC) to investigate trans-species
prion conversion.
To assess trans-species conversion in the RT-QuIC system, we compared
chronic wasting disease (CWD) and bovine spongiform encephalopathy (BSE) prions,
as well as feline CWD (fCWD) and feline spongiform encephalopathy (FSE). Each
prion was seeded into each host recombinant PrP (full-length rPrP of
white-tailed deer, bovine or feline). We demonstrated that fCWD is a more
efficient seed for feline rPrP than for white-tailed deer rPrP, which suggests
adaptation to the new host.
Conversely, FSE maintained sufficient BSE characteristics to more
efficiently convert bovine rPrP than feline rPrP. Additionally, human rPrP was
competent for conversion by CWD and fCWD. ***This insinuates that, at the level
of protein:protein interactions, the barrier preventing transmission of CWD to
humans is less robust than previously estimated.
================
***This insinuates that, at the level of protein:protein interactions, the
barrier preventing transmission of CWD to humans is less robust than previously
estimated.***
================
Willingham, Erin McNulty, Kelly Anderson, Jeanette Hayes-Klug, Amy Nalls,
and Candace Mathiason Colorado State University; Fort Collins, CO USA
Chronic wasting disease (CWD) is the transmissible spongiform
encephalopathy (TSE), of free-ranging and captive cervids (deer, elk and moose).
The presence of infectious prions in the tissues, bodily fluids and
environments of clinical and preclinical CWD-infected animals is thought to
account for its high transmission efficiency. Recently it has been recognized
that mother to offspring transmission may contribute to the facile transmission
of some TSEs. Although the mechanism behind maternal transmission is not yet
known, the extended asymptomatic TSE carrier phase (lasting years to decades)
suggests that it may have implications in the spread of prions.
Placental trafficking and/or secretion in milk are 2 means by which
maternal prion transmission may occur. In these studies we explore these avenues
during early and late infection using a transgenic mouse model expressing cervid
prion protein. Na€ıve and CWD-infected dams were bred at both timepoints, and
were allowed to bear and raise their offspring. Milk was collected from the dams
for prion analysis, and the offspring were observed for TSE disease progression.
Terminal tissues harvested from both dams and offspring were analyzed for
prions.
We have demonstrated that
(1) CWD infected TgCerPRP females successfully breed and bear offspring,
and
(2) the presence of PrPCWD in reproductive and mammary tissue from
CWD-infected dams.
We are currently analyzing terminal tissue harvested from offspring born to
CWD-infected dams for the detection of PrPCWD and amplification competent
prions. These studies will provide insight into the potential mechanisms and
biological significance associated with mother to offspring transmission of
TSEs.
==============
P.157: Uptake of prions into plants
Christopher Johnson1, Christina Carlson1, Matthew Keating1,2, Nicole
Gibbs1, Haeyoon Chang1, Jamie Wiepz1, and Joel Pedersen1 1USGS National Wildlife
Health Center; Madison, WI USA; 2University of Wisconsin - Madison; Madison, WI
USA
Soil may preserve chronic wasting disease (CWD) and scrapie infectivity in
the environment, making consumption or inhalation of soil particles a plausible
mechanism whereby na€ıve animals can be exposed to prions. Plants are known to
absorb a variety of substances from soil, including whole proteins, yet the
potential for plants to take up abnormal prion protein (PrPTSE) and preserve
prion infectivity is not known. In this study, we assessed PrPTSE uptake into
roots using laser scanning confocal microscopy with fluorescently tagged PrPTSE
and we used serial protein misfolding cyclic amplification (sPMCA) and detect
and quantify PrPTSE levels in plant aerial tissues. Fluorescence was identified
in the root hairs of the model plant Arabidopsis thaliana, as well as the crop
plants alfalfa (Medicago sativa), barley (Hordeum vulgare) and tomato (Solanum
lycopersicum) upon exposure to tagged PrPTSE but not a tagged control
preparation. Using sPMCA, we found evidence of PrPTSE in aerial tissues of A.
thaliana, alfalfa and maize (Zea mays) grown in hydroponic cultures in which
only roots were exposed to PrPTSE. Levels of PrPTSE in plant aerial tissues
ranged from approximately 4 £ 10 ¡10 to 1 £ 10 ¡9 g PrPTSE g ¡1 plant dry weight
or 2 £ 105 to 7 £ 106 intracerebral ID50 units g ¡1 plant dry weight. Both stems
and leaves of A. thaliana grown in culture media containing prions are
infectious when intracerebrally-injected into mice. ***Our results suggest that
prions can be taken up by plants and that contaminated plants may represent a
previously unrecognized risk of human, domestic species and wildlife exposure to
prions.
===========
***Our results suggest that prions can be taken up by plants and that
contaminated plants may represent a previously unrecognized risk of human,
domestic species and wildlife exposure to prions.***
SEE ;
Friday, May 15, 2015
Grass Plants Bind, Retain, Uptake, and Transport Infectious Prions
Report
============
P.19: Characterization of chronic wasting disease isolates from freeranging
deer (Odocoileus sp) in Alberta and Saskatchewan, Canada
Camilo Duque Velasquez1, Chiye Kim1, Nathalie Daude1, Jacques van der
Merwe1, Allen Herbst1, Trent Bollinger2, Judd Aiken1, and Debbie McKenzie1
1Centre for Prions and Protein Folding Diseases; University of Alberta;
Edmonton, Canada; 2Western College of Veterinary Medicine; University of
Saskatchewan; Saskatoon, Canada
Chronic wasting disease (CWD) is an emerging prion disease of free ranging
and captive species of Cervidae. In North America, CWD is enzootic in some wild
cervid populations and can circulate among different deer species. The
contagious nature of CWD prions and the variation of cervid PRNP alleles, which
influence host susceptibility, can result in the emergence and adaptation of
different CWD strains. These strains may impact transmission host range, disease
diagnosis, spread dynamics and efficacy of potential vaccines. We are
characterizing different CWD agents by biochemical analysis of the PrPCWD
conformers, propagation in vitro cell assays1 and by comparing transmission
properties and neuropathology in Tg33 (Q95G96) and Tg60 (Q95S96) mice.2 Although
Tg60 mice expressing S96- PrPC have been shown resistant to CWD infectivity from
various cervid species,2,3
***these transgenic mice are susceptible to H95 C CWD, a CWD strain derived
from experimental infection of deer expressing H95G96-PrPC. The diversity of
strains present in free-ranging mule deer (Odocoileus hemionus) and white-tailed
deer (Odocoileus virginianus) from Alberta and Saskatchewan is being determined
and will allow us to delineate the properties of CWD agents circulating in CWD
enzootic cervid populations of Canada.
References
1. van der Merwe J, Aiken J, Westaway D, McKenzie D. The standard scrapie
cell assay: Development, utility and prospects. Viruses 2015; 7(1):180–198;
PMID:25602372; http://dx.doi.org/10.3390/v7010180
2. Meade-White K, Race B, Trifilo M, Bossers A, Favara C, Lacasse R, Miller
M, Williams E, Oldstone M, Race R, Chesebro B. Resistance to chronic wasting
disease in transgenic mice expressing a naturally occurring allelic variant of
deer prion protein. J Virol 2007; 81(9):4533–4539; PMID: 17314157; http://dx. doi.org/10.1128/JVI.02762-06
3. Race B, Meade-White K, Miller MW, Fox KA, Chesebro B. In vivo comparison
of chronic wasting disease infectivity from deer with variation at prion protein
residue 96. J Virol 2011; 85(17):9235–9238; PMID: 21697479; http://dx.doi.org/10.1128/JVI.00790-11
=========
***these transgenic mice are susceptible to H95 C CWD, a CWD strain derived
from experimental infection of deer expressing H95G96-PrPC.
==========
P.136: Mother to offspring transmission of CWD—Detection in fawn tissues
using the QuIC assay
Amy Nalls, Erin McNulty, Clare Hoover, Jeanette Hayes-Klug, Kelly Anderson,
Edward Hoover, and Candace Mathiason Colorado State University; Fort Collins, CO
USA
To investigate the role mother to offspring transmission plays in chronic
wasting disease (CWD), we have employed a small, polyestrous breeding, indoor
maintainable cervid model, the Reeves’ muntjac deer. Muntjac doe were inoculated
with CWD and tested positive by lymphoid biopsy at 4 months post inoculation.
From these CWD-infected doe, we obtained 3 viable fawns. These fawns tested
IHC-positive for CWD by lymphoid biopsy as early as 40 d post birth, and all
have been euthanized due to clinical disease at 31, 34 and 59 months post birth.
The QuIC assay demonstrates sensitivity and specificity in the detection of
conversion competent prions in peripheral IHC-positive tissues including tonsil,
mandibular, partotid, retropharyngeal, and prescapular lymph nodes, adrenal
gland, spleen and liver. In summary, using the muntjac deer model, we have
demonstrated CWD clinical disease in offspring born to CWD-infected doe and
found that the QuIC assay is an effective tool in the detection of prions in
peripheral tissues. ***Our findings demonstrate that transmission of prions from
mother to offspring can occur, and may be underestimated for all prion
diseases.
===============
***Our findings demonstrate that transmission of prions from mother to
offspring can occur, and may be underestimated for all prion diseases.
===============
I strenuously once again urge the FDA and its industry constituents, to
make it MANDATORY that all ruminant feed be banned to all ruminants, and this
should include all cervids as soon as possible for the following
reasons...
======
In the USA, under the Food and Drug Administrations BSE Feed Regulation (21
CFR 589.2000) most material (exceptions include milk, tallow, and gelatin) from
deer and elk is prohibited for use in feed for ruminant animals. With regards to
feed for non-ruminant animals, under FDA law, CWD positive deer may not be used
for any animal feed or feed ingredients. For elk and deer considered at high
risk for CWD, the FDA recommends that these animals do not enter the animal feed
system.
***However, this recommendation is guidance and not a requirement by law.
======
31 Jan 2015 at 20:14 GMT
*** Ruminant feed ban for cervids in the United States? ***
31 Jan 2015 at 20:14 GMT
cwd environmental load factor in the land and surrounding plants and
objects.
transportation of cervids and HUMANS from cwd zone should be regarded as a
great risk factor, and environmental contamination.
PL1
Using in vitro prion replication for high sensitive detection of prions and
prionlike proteins and for understanding mechanisms of transmission.
Claudio Soto
Mitchell Center for Alzheimer's diseases and related Brain disorders,
Department of Neurology, University of Texas Medical School at Houston.
Prion and prion-like proteins are misfolded protein aggregates with the
ability to selfpropagate to spread disease between cells, organs and in some
cases across individuals. I n T r a n s m i s s i b l e s p o n g i f o r m
encephalopathies (TSEs), prions are mostly composed by a misfolded form of the
prion protein (PrPSc), which propagates by transmitting its misfolding to the
normal prion protein (PrPC). The availability of a procedure to replicate prions
in the laboratory may be important to study the mechanism of prion and
prion-like spreading and to develop high sensitive detection of small quantities
of misfolded proteins in biological fluids, tissues and environmental samples.
Protein Misfolding Cyclic Amplification (PMCA) is a simple, fast and efficient
methodology to mimic prion replication in the test tube. PMCA is a platform
technology that may enable amplification of any prion-like misfolded protein
aggregating through a seeding/nucleation process. In TSEs, PMCA is able to
detect the equivalent of one single molecule of infectious PrPSc and propagate
prions that maintain high infectivity, strain properties and species
specificity. Using PMCA we have been able to detect PrPSc in blood and urine of
experimentally infected animals and humans affected by vCJD with high
sensitivity and specificity. Recently, we have expanded the principles of PMCA
to amplify amyloid-beta (Aβ) and alphasynuclein (α-syn) aggregates implicated in
Alzheimer's and Parkinson's diseases, respectively. Experiments are ongoing to
study the utility of this technology to detect Aβ and α-syn aggregates in
samples of CSF and blood from patients affected by these diseases.
***Recently, we have been using PMCA to study the role of environmental
prion contamination on the horizontal spreading of TSEs. These experiments have
focused on the study of the interaction of prions with plants and
environmentally relevant surfaces. Our results show that plants (both leaves and
roots) bind tightly to prions present in brain extracts and excreta (urine and
feces) and retain even small quantities of PrPSc for long periods of time.
Strikingly, ingestion of prioncontaminated leaves and roots produced disease
with a 100% attack rate and an incubation period not substantially longer than
feeding animals directly with scrapie brain homogenate. Furthermore, plants can
uptake prions from contaminated soil and transport them to different parts of
the plant tissue (stem and leaves). Similarly, prions bind tightly to a variety
of environmentallyrelevant surfaces, including stones, wood, metals, plastic,
glass, cement, etc. Prion contaminated surfaces efficiently transmit prion
disease when these materials were directly injected into the brain of animals
and strikingly when the contaminated surfaces were just placed in the animal
cage. These findings demonstrate that environmental materials can efficiently
bind infectious prions and act as carriers of infectivity, suggesting that they
may play an important role in the horizontal transmission of the disease.
Since its invention 13 years ago, PMCA has helped to answer fundamental
questions of prion propagation and has broad applications in research areas
including the food industry, blood bank safety and human and veterinary disease
diagnosis.
Wednesday, June 10, 2015
Zoonotic Potential of CWD Prions
LATE-BREAKING ABSTRACTS
O.05: Transmission of prions to primates after extended silent incubation
periods: Implications for BSE and scrapie risk assessment in human populations
Emmanuel Comoy, Jacqueline Mikol, Val erie Durand, Sophie Luccantoni,
Evelyne Correia, Nathalie Lescoutra, Capucine Dehen, and Jean-Philippe Deslys
Atomic Energy Commission; Fontenay-aux-Roses, France
Prion diseases (PD) are the unique neurodegenerative proteinopathies
reputed to be transmissible under field conditions since decades. The
transmission of Bovine Spongiform Encephalopathy (BSE) to humans evidenced that
an animal PD might be zoonotic under appropriate conditions. Contrarily, in the
absence of obvious (epidemiological or experimental) elements supporting a
transmission or genetic predispositions, PD, like the other proteinopathies, are
reputed to occur spontaneously (atpical animal prion strains, sporadic CJD
summing 80% of human prion cases). Non-human primate models provided the first
evidences supporting the transmissibiity of human prion strains and the zoonotic
potential of BSE. Among them, cynomolgus macaques brought major information for
BSE risk assessment for human health (Chen, 2014), according to their
phylogenetic proximity to humans and extended lifetime. We used this model to
assess the zoonotic potential of other animal PD from bovine, ovine and cervid
origins even after very long silent incubation periods. *** We recently observed
the direct transmission of a natural classical scrapie isolate to macaque after
a 10-year silent incubation period, ***with features similar to some reported
for human cases of sporadic CJD, albeit requiring fourfold longe incubation than
BSE. Scrapie, as recently evoked in humanized mice (Cassard, 2014), ***is the
third potentially zoonotic PD (with BSE and L-type BSE), ***thus questioning the
origin of human sporadic cases. We will present an updated panorama of our
different transmission studies and discuss the implications of such extended
incubation periods on risk assessment of animal PD for human health.
===============
***thus questioning the origin of human sporadic cases...TSS
===============
Friday, January 30, 2015
*** Scrapie: a particularly persistent pathogen ***
98 | Veterinary Record | January 24, 2015
EDITORIAL
Scrapie: a particularly persistent pathogen
Cristina Acín
Resistant prions in the environment have been the sword of Damocles for
scrapie control and eradication. Attempts to establish which physical and
chemical agents could be applied to inactivate or moderate scrapie infectivity
were initiated in the 1960s and 1970s,with the first study of this type focusing
on the effect of heat treatment in reducing prion infectivity (Hunter and
Millson 1964). Nowadays, most of the chemical procedures that aim to inactivate
the prion protein are based on the method developed by Kimberlin and
collaborators (1983). This procedure consists of treatment with 20,000 parts per
million free chlorine solution, for a minimum of one hour, of all surfaces that
need to be sterilised (in laboratories, lambing pens, slaughterhouses, and so
on). Despite this, veterinarians and farmers may still ask a range of questions,
such as ‘Is there an official procedure published somewhere?’ and ‘Is there an
international organisation which recommends and defines the exact method of
scrapie decontamination that must be applied?’
From a European perspective, it is difficult to find a treatment that could
be applied, especially in relation to the disinfection of surfaces in lambing
pens of affected flocks. A 999/2001 EU regulation on controlling spongiform
encephalopathies (European Parliament and Council 2001) did not specify a
particular decontamination measure to be used when an outbreak of scrapie is
diagnosed. There is only a brief recommendation in Annex VII concerning the
control and eradication of transmissible spongiform encephalopathies (TSE
s).
Chapter B of the regulation explains the measures that must be applied if
new caprine animals are to be introduced to a holding where a scrapie outbreak
has previously been diagnosed. In that case, the statement indicates that
caprine animals can be introduced ‘provided that a cleaning and disinfection of
all animal housing on the premises has been carried out following
destocking’.
Issues around cleaning and disinfection are common in prion prevention
recommendations, but relevant authorities, veterinarians and farmers may have
difficulties in finding the specific protocol which applies. The European Food
and Safety Authority (EFSA ) published a detailed report about the efficacy of
certain biocides, such as sodium hydroxide, sodium hypochlorite, guanidine and
even a formulation of copper or iron metal ions in combination with hydrogen
peroxide, against prions (EFSA 2009). The report was based on scientific
evidence (Fichet and others 2004, Lemmer and others 2004, Gao and others 2006,
Solassol and others 2006) but unfortunately the decontamination measures were
not assessed under outbreak conditions.
The EFSA Panel on Biological Hazards recently published its conclusions on
the scrapie situation in the EU after 10 years of monitoring and control of the
disease in sheep and goats (EFSA 2014), and one of the most interesting findings
was the Icelandic experience regarding the effect of disinfection in scrapie
control. The Icelandic plan consisted of: culling scrapie-affected sheep or the
whole flock in newly diagnosed outbreaks; deep cleaning and disinfection of
stables, sheds, barns and equipment with high pressure washing followed by
cleaning with 500 parts per million of hypochlorite; drying and treatment with
300 ppm of iodophor; and restocking was not permitted for at least two years.
Even when all of these measures were implemented, scrapie recurred on several
farms, indicating that the infectious agent survived for years in the
environment, even as many as 16 years after restocking (Georgsson and others
2006).
In the rest of the countries considered in the EFSA (2014) report,
recommendations for disinfection measures were not specifically defined at the
government level. In the report, the only recommendation that is made for sheep
is repopulation with sheep with scrapie-resistant genotypes. This reduces the
risk of scrapie recurrence but it is difficult to know its effect on the
infection.
Until the EFSA was established (in May 2003), scientific opinions about TSE
s were provided by the Scientific Steering Committee (SSC) of the EC, whose
advice regarding inactivation procedures focused on treating animal waste at
high temperatures (150°C for three hours) and high pressure alkaline hydrolysis
(SSC 2003). At the same time, the TSE Risk Management Subgroup of the Advisory
Committee on Dangerous Pathogens (ACDP) in the UK published guidance on safe
working and the prevention of TSE infection. Annex C of the ACDP report
established that sodium hypochlorite was considered to be effective, but only if
20,000 ppm of available chlorine was present for at least one hour, which has
practical limitations such as the release of chlorine gas, corrosion,
incompatibility with formaldehyde, alcohols and acids, rapid inactivation of its
active chemicals and the stability of dilutions (ACDP 2009).
In an international context, the World Organisation for Animal Health (OIE)
does not recommend a specific disinfection protocol for prion agents in its
Terrestrial Code or Manual. Chapter 4.13 of the Terrestrial Code, General
recommendations on disinfection and disinsection (OIE 2014), focuses on
foot-and-mouth disease virus, mycobacteria and Bacillus anthracis, but not on
prion disinfection. Nevertheless, the last update published by the OIE on bovine
spongiform encephalopathy (OIE 2012) indicates that few effective
decontamination techniques are available to inactivate the agent on surfaces,
and recommends the removal of all organic material and the use of sodium
hydroxide, or a sodium hypochlorite solution containing 2 per cent available
chlorine, for more than one hour at 20ºC.
The World Health Organization outlines guidelines for the control of TSE s,
and also emphasises the importance of mechanically cleaning surfaces before
disinfection with sodium hydroxide or sodium hypochlorite for one hour (WHO
1999).
Finally, the relevant agencies in both Canada and the USA suggest that the
best treatments for surfaces potentially contaminated with prions are sodium
hydroxide or sodium hypochlorite at 20,000 ppm. This is a 2 per cent solution,
while most commercial household bleaches contain 5.25 per cent sodium
hypochlorite. It is therefore recommended to dilute one part 5.25 per cent
bleach with 1.5 parts water (CDC 2009, Canadian Food Inspection Agency
2013).
So what should we do about disinfection against prions? First, it is
suggested that a single protocol be created by international authorities to
homogenise inactivation procedures and enable their application in all
scrapie-affected countries. Sodium hypochlorite with 20,000 ppm of available
chlorine seems to be the procedure used in most countries, as noted in a paper
summarised on p 99 of this issue of Veterinary Record (Hawkins and others 2015).
But are we totally sure of its effectiveness as a preventive measure in a
scrapie outbreak? Would an in-depth study of the recurrence of scrapie disease
be needed?
What we can conclude is that, if we want to fight prion diseases, and
specifically classical scrapie, we must focus on the accuracy of diagnosis,
monitoring and surveillance; appropriate animal identification and control of
movements; and, in the end, have homogeneous and suitable protocols to
decontaminate and disinfect lambing barns, sheds and equipment available to
veterinarians and farmers. Finally, further investigations into the resistance
of prion proteins in the diversity of environmental surfaces are required.
References
snip...
98 | Veterinary Record | January 24, 2015
Persistence of ovine scrapie infectivity in a farm environment following
cleaning and decontamination
Steve A. C. Hawkins, MIBiol, Pathology Department1, Hugh A. Simmons, BVSc
MRCVS, MBA, MA Animal Services Unit1, Kevin C. Gough, BSc, PhD2 and Ben C.
Maddison, BSc, PhD3 + Author Affiliations
1Animal and Plant Health Agency, Woodham Lane, New Haw, Addlestone, Surrey
KT15 3NB, UK 2School of Veterinary Medicine and Science, The University of
Nottingham, Sutton Bonington, Loughborough, Leicestershire LE12 5RD, UK 3ADAS
UK, School of Veterinary Medicine and Science, The University of Nottingham,
Sutton Bonington, Loughborough, Leicestershire LE12 5RD, UK E-mail for
correspondence: ben.maddison@adas.co.uk Abstract Scrapie of sheep/goats and
chronic wasting disease of deer/elk are contagious prion diseases where
environmental reservoirs are directly implicated in the transmission of disease.
In this study, the effectiveness of recommended scrapie farm decontamination
regimens was evaluated by a sheep bioassay using buildings naturally
contaminated with scrapie. Pens within a farm building were treated with either
20,000 parts per million free chorine solution for one hour or were treated with
the same but were followed by painting and full re-galvanisation or replacement
of metalwork within the pen. Scrapie susceptible lambs of the PRNP genotype
VRQ/VRQ were reared within these pens and their scrapie status was monitored by
recto-anal mucosa-associated lymphoid tissue. All animals became infected over
an 18-month period, even in the pen that had been subject to the most stringent
decontamination process. These data suggest that recommended current guidelines
for the decontamination of farm buildings following outbreaks of scrapie do
little to reduce the titre of infectious scrapie material and that environmental
recontamination could also be an issue associated with these premises.
SNIP...
Discussion
Thorough pressure washing of a pen had no effect on the amount of
bioavailable scrapie infectivity (pen B). The routine removal of prions from
surfaces within a laboratory setting is treatment for a minimum of one hour with
20,000 ppm free chlorine, a method originally based on the use of brain
macerates from infected rodents to evaluate the effectiveness of decontamination
(Kimberlin and others 1983). Further studies have also investigated the
effectiveness of hypochlorite disinfection of metal surfaces to simulate the
decontamination of surgical devices within a hospital setting. Such treatments
with hypochlorite solution were able to reduce infectivity by 5.5 logs to lower
than the sensitivity of the bioassay used (Lemmer and others 2004). Analogous
treatment of the pen surfaces did not effectively remove the levels of scrapie
infectivity over that of the control pens, indicating that this method of
decontamination is not effective within a farm setting. This may be due to the
high level of biological matrix that is present upon surfaces within the farm
environment, which may reduce the amount of free chlorine available to
inactivate any infectious prion. Remarkably 1/5 sheep introduced into pen D had
also became scrapie positive within nine months, with all animals in this pen
being RAMALT positive by 18 months of age. Pen D was no further away from the
control pen (pen A) than any of the other pens within this barn. Localised hot
spots of infectivity may be present within scrapie-contaminated environments,
but it is unlikely that pen D area had an amount of scrapie contamination that
was significantly different than the other areas within this building.
Similarly, there were no differences in how the biosecurity of pen D was
maintained, or how this pen was ventilated compared with the other pens. This
observation, perhaps, indicates the slower kinetics of disease uptake within
this pen and is consistent with a more thorough prion removal and
recontamination. These observations may also account for the presence of
inadvertent scrapie cases within other studies, where despite stringent
biosecurity, control animals have become scrapie positive during challenge
studies using barns that also housed scrapie-affected animals (Ryder and others
2009). The bioassay data indicate that the exposure of the sheep to a farm
environment after decontamination efforts thought to be effective in removing
scrapie is sufficient for the animals to become infected with scrapie. The main
exposure routes within this scenario are likely to be via the oral route, during
feeding and drinking, and respiratory and conjunctival routes. It has been
demonstrated that scrapie infectivity can be efficiently transmitted via the
nasal route in sheep (Hamir and others 2008), as is the case for CWD in both
murine models and in white-tailed deer (Denkers and others 2010, 2013).
Recently, it has also been demonstrated that CWD prions presented as dust when
bound to the soil mineral montmorillonite can be infectious via the nasal route
(Nichols and others 2013). When considering pens C and D, the actual source of
the infectious agent in the pens is not known, it is possible that biologically
relevant levels of prion survive on surfaces during the decontamination regimen
(pen C). With the use of galvanising and painting (pen D) covering and sealing
the surface of the pen, it is possible that scrapie material recontaminated the
pens by the movement of infectious prions contained within dusts originating
from other parts of the barn that were not decontaminated or from other areas of
the farm.
Given that scrapie prions are widespread on the surfaces of affected farms
(Maddison and others 2010a), irrespective of the source of the infectious prions
in the pens, this study clearly highlights the difficulties that are faced with
the effective removal of environmentally associated scrapie infectivity. This is
likely to be paralleled in CWD which shows strong similarities to scrapie in
terms of both the dissemination of prions into the environment and the facile
mode of disease transmission. These data further contribute to the understanding
that prion diseases can be highly transmissible between susceptible individuals
not just by direct contact but through highly stable environmental reservoirs
that are refractory to decontamination.
The presence of these environmentally associated prions in farm buildings
make the control of these diseases a considerable challenge, especially in
animal species such as goats where there is lack of genetic resistance to
scrapie and, therefore, no scope to re-stock farms with animals that are
resistant to scrapie.
Scrapie Sheep Goats Transmissible spongiform encephalopathies (TSE)
Accepted October 12, 2014. Published Online First 31 October 2014
Monday, November 3, 2014
Persistence of ovine scrapie infectivity in a farm environment following
cleaning and decontamination
PPo3-22:
Detection of Environmentally Associated PrPSc on a Farm with Endemic
Scrapie
Ben C. Maddison,1 Claire A. Baker,1 Helen C. Rees,1 Linda A. Terry,2 Leigh
Thorne,2 Susan J. Belworthy2 and Kevin C. Gough3 1ADAS-UK LTD; Department of
Biology; University of Leicester; Leicester, UK; 2Veterinary Laboratories
Agency; Surry, KT UK; 3Department of Veterinary Medicine and Science; University
of Nottingham; Sutton Bonington, Loughborough UK
Key words: scrapie, evironmental persistence, sPMCA
Ovine scrapie shows considerable horizontal transmission, yet the routes of
transmission and specifically the role of fomites in transmission remain poorly
defined. Here we present biochemical data demonstrating that on a
scrapie-affected sheep farm, scrapie prion contamination is widespread. It was
anticipated at the outset that if prions contaminate the environment that they
would be there at extremely low levels, as such the most sensitive method
available for the detection of PrPSc, serial Protein Misfolding Cyclic
Amplification (sPMCA), was used in this study. We investigated the distribution
of environmental scrapie prions by applying ovine sPMCA to samples taken from a
range of surfaces that were accessible to animals and could be collected by use
of a wetted foam swab. Prion was amplified by sPMCA from a number of these
environmental swab samples including those taken from metal, plastic and wooden
surfaces, both in the indoor and outdoor environment. At the time of sampling
there had been no sheep contact with these areas for at least 20 days prior to
sampling indicating that prions persist for at least this duration in the
environment. These data implicate inanimate objects as environmental reservoirs
of prion infectivity which are likely to contribute to disease transmission.
Friday, May 22, 2015
*** Chronic Wasting Disease and Program Updates - 2014 NEUSAHA Annual
Meeting 12-14 May 2014 ***
Saturday, May 30, 2015
PRION 2015 ORAL AND POSTER CONGRESSIONAL ABSTRACTS
*** here we go again. more cwd exposed cervid escape into the wild
***
*** see other escapees from cwd exposed herds, that escaped into the wild,
never to be found, from other states, in the following link ***
Tuesday, July 14, 2015
TWO Escaped Captive Deer on the loose in Eau Claire County Wisconsin CWD
postive farm Yellow ear tag
>>> At Monday's hearing, Rep. Lyle Larson, R-San Antonio, called
the action "a draconian approach" and urged TPWD and TAHC officials to consider
using live tests or other options that would not involve killing scores of deer.
<<<
as usual, and this does not surprise me, you will have politicians coming
out of the woodwork, that have no clue on the science of cwd, and ramifications
there from, that will come out and try and save infected cwd herd. bottom line,
like everything else, they ignored this cwd for decades, and now that cwd is in
their backyard, they will now seek to change the science, thus spreading more
cwd to hell and back. Texas will deserve exactly what it gets from their
ignorance. these rectum biopsy test, and other cwd tse prion test, have NOT been
validated for full use, they are years, if not decades in the future, if they
can ever become 100% validated. but until then, and until every cervid can be
tested, the scorched earth policy is the only policy, to slow this spread of the
CWD TSE prion aka mad cow type agent. if anyone in Texas even cares, here is the
latest science on this matter ;
The TSE prion disease survives ashing to 600 degrees celsius, that’s around
1112 degrees farenheit.
you cannot cook the TSE prion disease out of meat.
you can take the ash and mix it with saline and inject that ash into a
mouse, and the mouse will go down with TSE.
Prion Infected Meat-and-Bone Meal Is Still Infectious after Biodiesel
Production as well.
the TSE prion agent also survives Simulated Wastewater Treatment Processes.
IN fact, you should also know that the TSE Prion agent will survive in the
environment for years, if not decades.
you can bury it and it will not go away.
The TSE agent is capable of infected your water table i.e. Detection of
protease-resistant cervid prion protein in water from a CWD-endemic area.
it’s not your ordinary pathogen you can just cook it out and be done with.
that’s what’s so worrisome about Iatrogenic mode of transmission, a simple
autoclave will not kill this TSE prion agent.
New studies on the heat resistance of hamster-adapted scrapie agent:
Threshold survival after ashing at 600°C suggests an inorganic template of
replication
The infectious agents responsible for transmissible spongiform
encephalopathy (TSE) are notoriously resistant to most physical and chemical
methods used for inactivating pathogens, including heat. It has long been
recognized, for example, that boiling is ineffective and that higher
temperatures are most efficient when combined with steam under pressure (i.e.,
autoclaving). As a means of decontamination, dry heat is used only at the
extremely high temperatures achieved during incineration, usually in excess of
600°C. It has been assumed, without proof, that incineration totally inactivates
the agents of TSE, whether of human or animal origin.
Prion Infected Meat-and-Bone Meal Is Still Infectious after Biodiesel
Production
Histochemical analysis of hamster brains inoculated with the solid residue
showed typical spongiform degeneration and vacuolation. Re-inoculation of these
brains into a new cohort of hamsters led to onset of clinical scrapie symptoms
within 75 days, suggesting that the specific infectivity of the prion protein
was not changed during the biodiesel process. The biodiesel reaction cannot be
considered a viable prion decontamination method for MBM, although we observed
increased survival time of hamsters and reduced infectivity greater than 6 log
orders in the solid MBM residue. Furthermore, results from our study compare for
the first time prion detection by Western Blot versus an infectivity bioassay
for analysis of biodiesel reaction products. We could show that biochemical
analysis alone is insufficient for detection of prion infectivity after a
biodiesel process.
Detection of protease-resistant cervid prion protein in water from a
CWD-endemic area
The data presented here demonstrate that sPMCA can detect low levels of
PrPCWD in the environment, corroborate previous biological and experimental data
suggesting long term persistence of prions in the environment2,3 and imply that
PrPCWD accumulation over time may contribute to transmission of CWD in areas
where it has been endemic for decades. This work demonstrates the utility of
sPMCA to evaluate other environmental water sources for PrPCWD, including
smaller bodies of water such as vernal pools and wallows, where large numbers of
cervids congregate and into which prions from infected animals may be shed and
concentrated to infectious levels.
A Quantitative Assessment of the Amount of Prion Diverted to Category 1
Materials and Wastewater During Processing
Keywords:Abattoir;bovine spongiform encephalopathy;QRA;scrapie;TSE
In this article the development and parameterization of a quantitative
assessment is described that estimates the amount of TSE infectivity that is
present in a whole animal carcass (bovine spongiform encephalopathy [BSE] for
cattle and classical/atypical scrapie for sheep and lambs) and the amounts that
subsequently fall to the floor during processing at facilities that handle
specified risk material (SRM). BSE in cattle was found to contain the most oral
doses, with a mean of 9864 BO ID50s (310, 38840) in a whole carcass compared to
a mean of 1851 OO ID50s (600, 4070) and 614 OO ID50s (155, 1509) for a sheep
infected with classical and atypical scrapie, respectively. Lambs contained the
least infectivity with a mean of 251 OO ID50s (83, 548) for classical scrapie
and 1 OO ID50s (0.2, 2) for atypical scrapie. The highest amounts of infectivity
falling to the floor and entering the drains from slaughtering a whole carcass
at SRM facilities were found to be from cattle infected with BSE at rendering
and large incineration facilities with 7.4 BO ID50s (0.1, 29), intermediate
plants and small incinerators with a mean of 4.5 BO ID50s (0.1, 18), and
collection centers, 3.6 BO ID50s (0.1, 14). The lowest amounts entering drains
are from lambs infected with classical and atypical scrapie at intermediate
plants and atypical scrapie at collection centers with a mean of 3 × 10−7 OO
ID50s (2 × 10−8, 1 × 10−6) per carcass. The results of this model provide key
inputs for the model in the companion paper published here.
*** Infectious agent of sheep scrapie may persist in the environment for at
least 16 years***
Gudmundur Georgsson1, Sigurdur Sigurdarson2 and Paul Brown3
Longitudinal Detection of Prion Shedding in Saliva and Urine by
CWD-Infected Deer by RT-QuIC
Davin M. Henderson1, Nathaniel D. Denkers1, Clare E. Hoover1, Nina
Garbino1, Candace K. Mathiason1 and Edward A. Hoover1# + Author
Affiliations
1Prion Research Center, Department of Microbiology, Immunology, and
Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado
State University, Fort Collins, CO 80523 ABSTRACT Chronic Wasting Disease (CWD)
is an emergent, rapidly spreading prion disease of cervids. Shedding of
infectious prions in saliva and urine is thought to be an important factor in
CWD transmission. To help elucidate this issue, we applied an in vitro
amplification assay to determine the onset, duration, and magnitude of prion
shedding in longitudinally collected saliva and urine samples from CWD-exposed
white-tailed deer. We detected prion shedding as early as 3 months after CWD
exposure and sustained shedding throughout the disease course. We estimated that
a 50% lethal dose (LD50) for cervidized transgenic mice would be contained in 1
ml of infected deer saliva or 10 ml or urine. Given the average course of
infection and daily production of these body fluids, an infected deer would shed
thousands of prion infectious dosesover the course of CWD infection. The direct
and indirect environmental impact of this magnitude of prion shedding for cervid
and non-cervid species is surely significant.
Importance: Chronic wasting disease (CWD) is an emerging and uniformly
fatal prion disease affecting free ranging deer and elk and now recognized in 22
United States and 2 C anadian Provinces. It is unique among prion diseases in
that it is transmitted naturally though wild populations. A major hypothesis for
CWD's florid spread is that prions are shed in excreta and transmitted via
direct or indirect environmental contact. Here we use a rapid in vitro assay to
show that infectious doses of CWD prions are in fact shed throughout the
multi-year disease course in deer. This finding is an important advance in
assessing the risks posed by shed CWD prions to animals as well as humans.
FOOTNOTES
↵#To whom correspondence should be addressed: Edward A. Hoover, Prion
Research Center, Department of Microbiology, Immunology and Pathology, Colorado
State University, Fort Collins, Colorado, US Email: edward.hoover@colostate.edu
what about CWD infection rates on some of these game farms ???
CHRONIC WASTING DISEASE CWD WISCONSIN Almond Deer (Buckhorn Flats)
FarmUpdate DECEMBER 2011The CWD infection rate was nearly 80%, the highest ever
in a North American captive herd. RECOMMENDATION: That the Board approve the
purchase of 80acres of land for $465,000 for the Statewide Wildlife Habitat
Program inPortage County and approve the restrictions on public use of the
site.SUMMARY:
For Immediate Release Thursday, October 2, 2014
Dustin Vande Hoef 515/281-3375 or 515/326-1616 (cell) or
Dustin.VandeHoef@IowaAgriculture.gov
TEST RESULTS FROM CAPTIVE DEER HERD WITH CHRONIC WASTING DISEASE RELEASED
79.8 percent of the deer tested positive for the disease
DES MOINES – The Iowa Department of Agriculture and Land Stewardship today
announced that the test results from the depopulation of a quarantined captive
deer herd in north-central Iowa showed that 284 of the 356 deer, or 79.8% of the
herd, tested positive for Chronic Wasting Disease (CWD). The owners of the
quarantined herd have entered into a fence maintenance agreement with the Iowa
Department of Agriculture and Land Stewardship,which requires the owners to
maintain the 8’ foot perimeter fence around the herd premises for five years
after the depopulation was complete and the premises had been cleaned and
disinfected CWD is a progressive, fatal, degenerative neurological disease of
farmed and free-ranging deer, elk, and moose. There is no known treatment or
vaccine for CWD. CWD is not a disease that affects humans.On July 18, 2012, USDA
Animal and Plant Health Inspection Service’s (APHIS)National Veterinary Services
Lab in Ames, IA confirmed that a male whitetail deer harvested from a hunting
preserve in southeast IA was positive for CWD. An investigation revealed that
this animal had just been introduced into the hunting preserve from the
above-referenced captive deer herd in north-central Iowa.The captive deer herd
was immediately quarantined to prevent the spread of CWD. The herd has remained
in quarantine until its depopulation on August 25 to 27, 2014.The Iowa
Department of Agriculture and Land Stewardship participated in a joint operation
to depopulate the infected herd with USDA Veterinary Services, which was the
lead agency, and USDA Wildlife Services.Federal indemnity funding became
available in 2014. USDA APHIS appraised the captive deer herd of 376 animals at
that time, which was before depopulation and testing, at $1,354,250. At that
time a herd plan was developed with the owners and officials from USDA and the
Iowa Department of Agriculture and Land Stewardship.Once the depopulation was
complete and the premises had been cleaned and disinfected, indemnity of
$917,100.00 from the USDA has been or will be paid to the owners as compensation
for the 356 captive deer depopulated.The Iowa Department of Agriculture and Land
Stewardship operates a voluntary CWD program for farms that sell live animals.
Currently 145 Iowa farms participate in the voluntary program. The
above-referenced captive deer facility left the voluntary CWD program prior to
the discovery of the disease as they had stopped selling live animals. All deer
harvested in a hunting preserve must be tested for CWD. -30-
*** see history of this CWD blunder here ;
On June 5, 2013, DNR conducted a fence inspection, after gaining approval
from surrounding landowners, and confirmed that the fenced had beencut or
removed in at least four separate locations; that the fence had degraded and was
failing to maintain the enclosure around the Quarantined Premises in at least
one area; that at least three gates had been opened;and that deer tracks were
visible in and around one of the open areas in the sand on both sides of the
fence, evidencing movement of deer into the Quarantined Premises.
Friday, December 14, 2012
DEFRA U.K. What is the risk of Chronic Wasting Disease CWD being introduced
into Great Britain? A Qualitative Risk Assessment October 2012
snip...
In the USA, under the Food and Drug Administration’s BSE Feed Regulation
(21 CFR 589.2000) most material (exceptions include milk, tallow, and gelatin)
from deer and elk is prohibited for use in feed for ruminant animals. With
regards to feed for non-ruminant animals, under FDA law, CWD positive deer may
not be used for any animal feed or feed ingredients. For elk and deer considered
at high risk for CWD, the FDA recommends that these animals do not enter the
animal feed system. However, this recommendation is guidance and not a
requirement by law.
Animals considered at high risk for CWD include:
1) animals from areas declared to be endemic for CWD and/or to be CWD
eradication zones and
2) deer and elk that at some time during the 60-month period prior to
slaughter were in a captive herd that contained a CWD-positive animal.
Therefore, in the USA, materials from cervids other than CWD positive
animals may be used in animal feed and feed ingredients for non-ruminants.
The amount of animal PAP that is of deer and/or elk origin imported from
the USA to GB can not be determined, however, as it is not specified in TRACES.
It may constitute a small percentage of the 8412 kilos of non-fish origin
processed animal proteins that were imported from US into GB in 2011.
Overall, therefore, it is considered there is a __greater than negligible
risk___ that (nonruminant) animal feed and pet food containing deer and/or elk
protein is imported into GB.
There is uncertainty associated with this estimate given the lack of data
on the amount of deer and/or elk protein possibly being imported in these
products.
snip...
36% in 2007 (Almberg et al., 2011). In such areas, population declines of
deer of up to 30 to 50% have been observed (Almberg et al., 2011). In areas of
Colorado, the prevalence can be as high as 30% (EFSA, 2011). The clinical signs
of CWD in affected adults are weight loss and behavioural changes that can span
weeks or months (Williams, 2005). In addition, signs might include excessive
salivation, behavioural alterations including a fixed stare and changes in
interaction with other animals in the herd, and an altered stance (Williams,
2005). These signs are indistinguishable from cervids experimentally infected
with bovine spongiform encephalopathy (BSE). Given this, if CWD was to be
introduced into countries with BSE such as GB, for example, infected deer
populations would need to be tested to differentiate if they were infected with
CWD or BSE to minimise the risk of BSE entering the human food-chain via
affected venison.
snip...
The rate of transmission of CWD has been reported to be as high as 30% and
can approach 100% among captive animals in endemic areas (Safar et al., 2008).
snip...
In summary, in endemic areas, there is a medium probability that the soil
and surrounding environment is contaminated with CWD prions and in a
bioavailable form. In rural areas where CWD has not been reported and deer are
present, there is a greater than negligible risk the soil is contaminated with
CWD prion.
snip...
In summary, given the volume of tourists, hunters and servicemen moving
between GB and North America, the probability of at least one person travelling
to/from a CWD affected area and, in doing so, contaminating their clothing,
footwear and/or equipment prior to arriving in GB is greater than negligible.
For deer hunters, specifically, the risk is likely to be greater given the
increased contact with deer and their environment. However, there is significant
uncertainty associated with these estimates.
snip...
Therefore, it is considered that farmed and park deer may have a higher
probability of exposure to CWD transferred to the environment than wild deer
given the restricted habitat range and higher frequency of contact with tourists
and returning GB residents.
snip...
Friday, December 14, 2012
DEFRA U.K. What is the risk of Chronic Wasting Disease CWD being introduced
into Great Britain? A Qualitative Risk Assessment October 2012
CHRONIC WASTING DISEASE CWD TSE PRION, how much does it pay to find CWD
$$$
CWD, spreading it around...
for the game farm industry, and their constituents, to continue to believe
that they are _NOT_, and or insinuate that they have _NEVER_ been part of the
problem, will only continue to help spread cwd. the game farming industry, from
the shooting pens, to the urine mills, the antler mills, the sperm mills, velvet
mills, shooting pens, to large ranches, are not the only problem, but it is
painfully obvious that they have been part of the problem for decades and
decades, just spreading it around, as with transportation and or exportation and
or importation of cervids from game farming industry, and have been proven to
spread cwd. no one need to look any further than South Korea blunder ;
===========================================
spreading cwd around...
Between 1996 and 2002, chronic wasting disease was diagnosed in 39 herds of
farmed elk in Saskatchewan in a single epidemic. All of these herds were
depopulated as part of the Canadian Food Inspection Agency’s (CFIA) disease
eradication program. Animals, primarily over 12 mo of age, were tested for the
presence CWD prions following euthanasia. Twenty-one of the herds were linked
through movements of live animals with latent CWD from a single infected source
herd in Saskatchewan, 17 through movements of animals from 7 of the secondarily
infected herds.
***The source herd is believed to have become infected via importation of
animals from a game farm in South Dakota where CWD was subsequently diagnosed
(7,4). A wide range in herd prevalence of CWD at the time of herd depopulation
of these herds was observed. Within-herd transmission was observed on some
farms, while the disease remained confined to the introduced animals on other
farms.
spreading cwd around...
Friday, May 13, 2011
Chronic Wasting Disease (CWD) outbreaks and surveillance program in the
Republic of Korea
Hyun-Joo Sohn, Yoon-Hee Lee, Min-jeong Kim, Eun-Im Yun, Hyo-Jin Kim,
Won-Yong Lee, Dong-Seob Tark, In- Soo Cho, Foreign Animal Disease Research
Division, National Veterinary Research and Quarantine Service, Republic of Korea
Chronic wasting disease (CWD) has been recognized as an important prion
disease in native North America deer and Rocky mountain elks. The disease is a
unique member of the transmissible spongiform encephalopathies (TSEs), which
naturally affects only a few species. CWD had been limited to USA and Canada
until 2000.
On 28 December 2000, information from the Canadian government showed that a
total of 95 elk had been exported from farms with CWD to Korea. These consisted
of 23 elk in 1994 originating from the so-called “source farm” in Canada, and 72
elk in 1997, which had been held in pre export quarantine at the “source
farm”.Based on export information of CWD suspected elk from Canada to Korea, CWD
surveillance program was initiated by the Ministry of Agriculture and Forestry
(MAF) in 2001.
All elks imported in 1997 were traced back, however elks imported in 1994
were impossible to identify. CWD control measures included stamping out of all
animals in the affected farm, and thorough cleaning and disinfection of the
premises. In addition, nationwide clinical surveillance of Korean native
cervids, and improved measures to ensure reporting of CWD suspect cases were
implemented.
Total of 9 elks were found to be affected. CWD was designated as a
notifiable disease under the Act for Prevention of Livestock Epidemics in 2002.
Additional CWD cases - 12 elks and 2 elks - were diagnosed in 2004 and
2005.
Since February of 2005, when slaughtered elks were found to be positive,
all slaughtered cervid for human consumption at abattoirs were designated as
target of the CWD surveillance program. Currently, CWD laboratory testing is
only conducted by National Reference Laboratory on CWD, which is the Foreign
Animal Disease Division (FADD) of National Veterinary Research and Quarantine
Service (NVRQS).
In July 2010, one out of 3 elks from Farm 1 which were slaughtered for the
human consumption was confirmed as positive. Consequently, all cervid – 54 elks,
41 Sika deer and 5 Albino deer – were culled and one elk was found to be
positive. Epidemiological investigations were conducted by Veterinary
Epidemiology Division (VED) of NVRQS in collaboration with provincial veterinary
services.
Epidemiologically related farms were found as 3 farms and all cervid at
these farms were culled and subjected to CWD diagnosis. Three elks and 5
crossbreeds (Red deer and Sika deer) were confirmed as positive at farm 2.
All cervids at Farm 3 and Farm 4 – 15 elks and 47 elks – were culled and
confirmed as negative.
Further epidemiological investigations showed that these CWD outbreaks were
linked to the importation of elks from Canada in 1994 based on circumstantial
evidences.
In December 2010, one elk was confirmed as positive at Farm 5.
Consequently, all cervid – 3 elks, 11 Manchurian Sika deer and 20 Sika deer –
were culled and one Manchurian Sika deer and seven Sika deer were found to be
positive. This is the first report of CWD in these sub-species of deer.
Epidemiological investigations found that the owner of the Farm 2 in CWD
outbreaks in July 2010 had co-owned the Farm 5.
In addition, it was newly revealed that one positive elk was introduced
from Farm 6 of Jinju-si Gyeongsang Namdo. All cervid – 19 elks, 15 crossbreed
(species unknown) and 64 Sika deer – of Farm 6 were culled, but all confirmed as
negative.
Chronic Wasting Disease Susceptibility of Four North American Rodents
Chad J. Johnson1*, Jay R. Schneider2, Christopher J. Johnson2, Natalie A.
Mickelsen2, Julia A. Langenberg3, Philip N. Bochsler4, Delwyn P. Keane4, Daniel
J. Barr4, and Dennis M. Heisey2 1University of Wisconsin School of Veterinary
Medicine, Department of Comparative Biosciences, 1656 Linden Drive, Madison WI
53706, USA 2US Geological Survey, National Wildlife Health Center, 6006
Schroeder Road, Madison WI 53711, USA 3Wisconsin Department of Natural
Resources, 101 South Webster Street, Madison WI 53703, USA 4Wisconsin Veterinary
Diagnostic Lab, 445 Easterday Lane, Madison WI 53706, USA *Corresponding author
email: cjohnson@svm.vetmed.wisc.edu
We intracerebrally challenged four species of native North American rodents
that inhabit locations undergoing cervid chronic wasting disease (CWD)
epidemics. The species were: deer mice (Peromyscus maniculatus), white-footed
mice (P. leucopus), meadow voles (Microtus pennsylvanicus), and red-backed voles
(Myodes gapperi). The inocula were prepared from the brains of hunter-harvested
white-tailed deer from Wisconsin that tested positive for CWD. Meadow voles
proved to be most susceptible, with a median incubation period of 272 days.
Immunoblotting and immunohistochemistry confirmed the presence of PrPd in the
brains of all challenged meadow voles. Subsequent passages in meadow voles lead
to a significant reduction in incubation period. The disease progression in
red-backed voles, which are very closely related to the European bank vole (M.
glareolus) which have been demonstrated to be sensitive to a number of TSEs, was
slower than in meadow voles with a median incubation period of 351 days. We
sequenced the meadow vole and red-backed vole Prnp genes and found three amino
acid (AA) differences outside of the signal and GPI anchor sequences. Of these
differences (T56-, G90S, S170N; read-backed vole:meadow vole), S170N is
particularly intriguing due its postulated involvement in "rigid loop" structure
and CWD susceptibility. Deer mice did not exhibit disease signs until nearly 1.5
years post-inoculation, but appear to be exhibiting a high degree of disease
penetrance. White-footed mice have an even longer incubation period but are also
showing high penetrance. Second passage experiments show significant shortening
of incubation periods. Meadow voles in particular appear to be interesting lab
models for CWD. These rodents scavenge carrion, and are an important food source
for many predator species. Furthermore, these rodents enter human and domestic
livestock food chains by accidental inclusion in grain and forage. Further
investigation of these species as potential hosts, bridge species, and
reservoirs of CWD is required.
Veterinary Pathology Onlinevet.sagepub.com Published online before print
February 27, 2014, doi: 10.1177/0300985814524798 Veterinary Pathology February
27, 2014 0300985814524798
Lesion Profiling and Subcellular Prion Localization of Cervid Chronic
Wasting Disease in Domestic Cats
D. M. Seelig1⇑ A. V. Nalls1 M. Flasik2 V. Frank1 S. Eaton2 C. K. Mathiason1
E. A. Hoover1 1Department of Microbiology, Immunology, and Pathology, Colorado
State University, Fort Collins, CO, USA 2Department of Biomedical Sciences,
Colorado State University, Fort Collins, CO, USA D. M. Seelig, University of
Minnesota, Department of Veterinary Clinical Sciences, Room 339 VetMedCtrS,
6192A (Campus Delivery Code), 1352 Boyd Ave, St Paul, MN 55108, USA. Email
address: dseelig@umn.edu
Abstract
Chronic wasting disease (CWD) is an efficiently transmitted, fatal, and
progressive prion disease of cervids with an as yet to be fully clarified host
range. While outbred domestic cats (Felis catus) have recently been shown to be
susceptible to experimental CWD infection, the neuropathologic features of the
infection are lacking. Such information is vital to provide diagnostic power in
the event of natural interspecies transmission and insights into host and strain
interactions in interspecies prion infection. Using light microscopy and
immunohistochemistry, we detail the topographic pattern of neural spongiosis
(the “lesion profile”) and the distribution of misfolded prion protein in the
primary and secondary passage of feline CWD (FelCWD). We also evaluated cellular
and subcellular associations between misfolded prion protein (PrPD) and central
nervous system neurons and glial cell populations. From these studies, we (1)
describe the novel neuropathologic profile of FelCWD, which is distinct from
either cervid CWD or feline spongiform encephalopathy (FSE), and (2) provide
evidence of serial passage-associated interspecies prion adaptation. In
addition, we demonstrate through confocal analysis the successful
co-localization of PrPD with neurons, astrocytes, microglia, lysosomes, and
synaptophysin, which, in part, implicates each of these in the neuropathology of
FelCWD. In conclusion, this work illustrates the simultaneous role of both host
and strain in the development of a unique FelCWD neuropathologic profile and
that such a profile can be used to discriminate between FelCWD and FSE.
prion chronic wasting disease immunohistochemistry interspecies cat feline
spongiform encephalopathy transmissible spongiform encephalopathy adaptation
species barrier
Monday, August 8, 2011 Susceptibility of Domestic Cats to CWD Infection
Oral.29: Susceptibility of Domestic Cats to CWD Infection
Amy Nalls, Nicholas J. Haley, Jeanette Hayes-Klug, Kelly Anderson, Davis M.
Seelig, Dan S. Bucy, Susan L. Kraft, Edward A. Hoover and Candace K.
Mathiason†
Colorado State University; Fort Collins, CO USA†Presenting author; Email:
ckm@lamar.colostate.edu
Domestic and non-domestic cats have been shown to be susceptible to one
prion disease, feline spongiform encephalopathy (FSE), thought to be transmitted
through consumption of bovine spongiform encephalopathy (BSE) contaminated meat.
Because domestic and free ranging felids scavenge cervid carcasses, including
those in CWD affected areas, we evaluated the susceptibility of domestic cats to
CWD infection experimentally. Groups of n = 5 cats each were inoculated either
intracerebrally (IC) or orally (PO) with CWD deer brain homogenate. Between
40–43 months following IC inoculation, two cats developed mild but progressive
symptoms including weight loss, anorexia, polydipsia, patterned motor behaviors
and ataxia—ultimately mandating euthanasia. Magnetic resonance imaging (MRI) on
the brain of one of these animals (vs. two age-matched controls) performed just
before euthanasia revealed increased ventricular system volume, more prominent
sulci, and T2 hyperintensity deep in the white matter of the frontal hemisphere
and in cortical grey distributed through the brain, likely representing
inflammation or gliosis. PrPRES and widely distributed peri-neuronal vacuoles
were demonstrated in the brains of both animals by immunodetection assays. No
clinical signs of TSE have been detected in the remaining primary passage cats
after 80 months pi. Feline-adapted CWD was sub-passaged into groups (n=4 or 5)
of cats by IC, PO, and IP/SQ routes. Currently, at 22 months pi, all five IC
inoculated cats are demonstrating abnormal behavior including increasing
aggressiveness, pacing, and hyper responsiveness.
*** Two of these cats have developed rear limb ataxia. Although the limited
data from this ongoing study must be considered preliminary, they raise the
potential for cervid-to-feline transmission in nature.
AD.63:
Susceptibility of domestic cats to chronic wasting disease
Amy V.Nalls,1 Candace Mathiason,1 Davis Seelig,2 Susan Kraft,1 Kevin
Carnes,1 Kelly Anderson,1 Jeanette Hayes-Klug1 and Edward A. Hoover1 1Colorado
State University; Fort Collins, CO USA; 2University of Minnesota; Saint Paul, MN
USA
Domestic and nondomestic cats have been shown to be susceptible to feline
spongiform encephalopathy (FSE), almost certainly caused by consumption of
bovine spongiform encephalopathy (BSE)-contaminated meat. Because domestic and
free-ranging nondomestic felids scavenge cervid carcasses, including those in
areas affected by chronic wasting disease (CWD), we evaluated the susceptibility
of the domestic cat (Felis catus) to CWD infection experimentally. Cohorts of 5
cats each were inoculated either intracerebrally (IC) or orally (PO) with
CWD-infected deer brain. At 40 and 42 mo post-inoculation, two IC-inoculated
cats developed signs consistent with prion disease, including a stilted gait,
weight loss, anorexia, polydipsia, patterned motor behaviors, head and tail
tremors, and ataxia, and progressed to terminal disease within 5 mo. Brains from
these two cats were pooled and inoculated into cohorts of cats by IC, PO, and
intraperitoneal and subcutaneous (IP/SC) routes. Upon subpassage, feline-adapted
CWD (FelCWD) was transmitted to all IC-inoculated cats with a decreased
incubation period of 23 to 27 mo. FelCWD was detected in the brains of all the
symptomatic cats by western blotting and immunohistochemistry and abnormalities
were seen in magnetic resonance imaging, including multifocal T2 fluid
attenuated inversion recovery (FLAIR) signal hyper-intensities, ventricular size
increases, prominent sulci, and white matter tract cavitation. Currently, 3 of 4
IP/SQ and 2 of 4 PO inoculared cats have developed abnormal behavior patterns
consistent with the early stage of feline CWD.
*** These results demonstrate that CWD can be transmitted and adapted to
the domestic cat, thus raising the issue of potential cervid-to- feline
transmission in nature.
www.landesbioscience.com
PO-081: Chronic wasting disease in the cat— Similarities to feline
spongiform encephalopathy (FSE)
FELINE SPONGIFORM ENCEPHALOPATHY FSE
DEFRA Department for Environment, Food & Rural Affairs
Area 307, London, SW1P 4PQ Telephone: 0207 904 6000 Direct line: 0207 904
6287 E-mail: h.mcdonagh.defra.gsi.gov.uk
GTN: FAX:
Mr T S Singeltary P.O. Box 42 Bacliff Texas USA 77518
21 November 2001
Dear Mr Singeltary
TSE IN HOUNDS
Thank you for e-mail regarding the hounds survey. I am sorry for the long
delay in responding.
As you note, the hound survey remains unpublished. However the Spongiform
Encephalopathy Advisory Committee (SEAC), the UK Government's independent
Advisory Committee on all aspects related to BSE-like disease, gave the hound
study detailed consideration at their meeting in January 1994. As a summary of
this meeting published in the BSE inquiry noted, the Committee were clearly
concerned about the work that had been carried out, concluding that there had
clearly been problems with it, particularly the control on the histology, and
that it was more or less inconclusive. However was agreed that there should be a
re-evaluation of the pathological material in the study.
Later, at their meeting in June 95, The Committee re-evaluated the hound
study to see if any useful results could be gained from it. The Chairman
concluded that there were varying opinions within the Committee on further work.
It did not suggest any further transmission studies and thought that the lack of
clinical data was a major weakness.
Overall, it is clear that SEAC had major concerns about the survey as
conducted. As a result it is likely that the authors felt that it would not
stand up to r~eer review and hence it was never published. As noted above, and
in the detailed minutes of the SEAC meeting in June 95, SEAC considered whether
additional work should be performed to examine dogs for evidence of TSE
infection. Although the Committee had mixed views about the merits of conducting
further work, the Chairman noted that when the Southwood Committee made their
recommendation to complete an assessment of possible spongiform disease in dogs,
no TSEs had been identified in other species and hence dogs were perceived as a
high risk population and worthy of study. However subsequent to the original
recommendation, made in 1990, a number of other species had been identified with
TSE ( e.g. cats) so a study in hounds was less
critical. For more details see- http://www.bseinquiry,
gov.uk/files/yb/1995/06/21005001 .pdf
As this study remains unpublished, my understanding is that the ownership
of the data essentially remains with the original researchers. Thus
unfortunately, I am unable to help with your request to supply information on
the hound survey directly. My only suggestion is that you contact one of the
researchers originally involved in the project, such as Gerald Wells. He can be
contacted at the following address.
Dr Gerald Wells, Veterinary Laboratories Agency, New Haw, Addlestone,
Surrey, KT 15 3NB, UK
You may also wish to be aware that since November 1994 all suspected cases
of spongiform encephalopathy in animals and poultry were made notifiable. Hence
since that date there has been a requirement for vets to report any suspect SE
in dogs for further investigation. To date there has never been positive
identification of a TSE in a dog.
I hope this is helpful
Yours sincerely 4
HUGH MCDONAGH BSE CORRESPONDENCE SECTION
======================================
HOUND SURVEY
I am sorry, but I really could have been a co-signatory of Gerald's
minute.
I do NOT think that we can justify devoting any resources to this study,
especially as larger and more important projects such as the pathogenesis study
will be quite demanding.
If there is a POLITICAL need to continue with the examination of hound
brains then it should be passed entirely to the VI Service.
J W WILESMITH Epidemiology Unit 18 October 1991
Mr. R Bradley
cc: Mr. G A H Wells
3.3. Mr R J Higgins in conjunction with Mr G A Wells and Mr A C Scott would
by the end of the year, indentify the three brains that were from the
''POSITIVE'' end of the lesion spectrum.
TSE in dogs have not been documented simply because OF THE ONLY STUDY,
those brain tissue samples were screwed up too. see my investigation of this
here, and to follow, later follow up, a letter from defra, AND SEE SUSPICIOUS
BRAIN TISSUE SAF's. ...TSS
TSE & HOUNDS
GAH WELLS (very important statement here...TSS)
HOUND STUDY
AS implied in the Inset 25 we must not _ASSUME_ that transmission of BSE to
other species will invariably present pathology typical of a scrapie-like
disease.
snip...
http://web.archive.org/web/20060307063542/http://www.bseinquiry.gov.uk/files/yb/1991/01/04004001.pdf
*** IBNC Tauopathy or TSE Prion disease, it appears, no one is sure
***
Posted by flounder on 03 Jul 2015 at 16:53 GMT
76 pages on hound study;
snip...
The spongiform changes were not pathognomonic (ie. conclusive proof) for
prion disease, as they were atypical, being largely present in white matter
rather than grey matter in the brain and spinal cord. However, Tony Scott, then
head of electron microscopy work on TSEs, had no doubt that these SAFs were
genuine and that these hounds therefore must have had a scrapie-like disease. I
reviewed all the sections myself (original notes appended) and although the
pathology was not typical, I could not exclude the possibility that this was a
scrapie-like disorder, as white matter vacuolation is seen in TSEs and Wallerian
degeneration was also present in the white matter of the hounds, another feature
of scrapie.
38.I reviewed the literature on hound neuropathology, and discovered that
micrographs and descriptive neuropathology from papers on 'hound ataxia'
mirrored those in material from Robert Higgins' hound survey. Dr Tony Palmer
(Cambridge) had done much of this work, and I obtained original sections from
hound ataxia cases from him. This enabled me provisionally to conclude that
Robert Higgins had in all probability detected hound ataxia, but also that hound
ataxia itself was possibly a TSE. Gerald Wells confirmed in 'blind' examination
of single restricted microscopic fields that there was no distinction between
the white matter vacuolation present in BSE and scrapie cases, and that
occurring in hound ataxia and the hound survey cases.
39.Hound ataxia had reportedly been occurring since the 1930's, and a known
risk factor for its development was the feeding to hounds of downer cows, and
particularly bovine offal. Circumstantial evidence suggests that bovine offal
may also be causal in FSE, and TME in mink. Despite the inconclusive nature of
the neuropathology, it was clearly evident that this putative canine spongiform
encephalopathy merited further investigation.
40.The inconclusive results in hounds were never confirmed, nor was the
link with hound ataxia pursued. I telephoned Robert Higgins six years after he
first sent the slides to CVL. I was informed that despite his submitting a
yearly report to the CVO including the suggestion that the hound work be
continued, no further work had been done since 1991. This was surprising, to say
the very least.
41.The hound work could have provided valuable evidence that a scrapie-like
agent may have been present in cattle offal long before the BSE epidemic was
recognised. The MAFF hound survey remains unpublished.
Histopathological support to various other published MAFF experiments
42.These included neuropathological examination of material from
experiments studying the attempted transmission of BSE to chickens and pigs (CVL
1991) and to mice (RVC 1994).
It was thought likely that at least some, and probably all, of the cases in
zoo animals were caused by the BSE agent. Strong support for this hypothesis
came from the findings of Bruce and others (1994) ( Bruce, M.E., Chree, A.,
McConnell, I., Foster, J., Pearson, G. & Fraser, H. (1994) Transmission of
bovine spongiform encephalopathy and scrapie to mice: strain variation and
species barrier. Philosophical Transactions of the Royal Society B 343, 405-411:
J/PTRSL/343/405 ), who demonstrated that the pattern of variation in incubation
period and lesion profile in six strains of mice inoculated with brain
homogenates from an affected kudu and the nyala, was similar to that seen when
this panel of mouse strains was inoculated with brain from cattle with BSE. The
affected zoo bovids were all from herds that were exposed to feeds that were
likely to have contained contaminated ruminant-derived protein and the zoo
felids had been exposed, if only occasionally in some cases, to tissues from
cattle unfit for human consumption.
snip...
NEW URL ;
Friday, March 8, 2013
Dogs may have been used to make Petfood and animal feed
*** IBNC Tauopathy or TSE Prion disease, it appears, no one is sure
***
Posted by flounder on 03 Jul 2015 at 16:53 GMT
OR-09: Canine spongiform encephalopathy—A new form of animal prion disease
Monique David, Mourad Tayebi UT Health; Houston, TX USA
It was also hypothesized that BSE might have originated from an
unrecognized sporadic or genetic case of bovine prion disease incorporated into
cattle feed or even cattle feed contaminated with prion-infected human remains.1
However, strong support for a genetic origin of BSE has recently been
demonstrated in an H-type BSE case exhibiting the novel mutation E211K.2
Furthermore, a specific prion protein strain causing BSE in cattle is believed
to be the etiological agent responsible for the novel human prion disease,
variant Creutzfeldt-Jakob disease (vCJD).3 Cases of vCJD have been identified in
a number countries, including France, Italy, Ireland, the Netherlands, Canada,
Japan, US and the UK with the largest number of cases. Naturally occurring
feline spongiform encephalopathy of domestic cats4 and spongiform
encephalopathies of a number of zoo animals so-called exotic ungulate
encephalopathies5,6 are also recognized as animal prion diseases, and are
thought to have resulted from the same BSE-contaminated food given to cattle and
humans, although and at least in some of these cases, a sporadic and/or genetic
etiology cannot be ruled out. The canine species seems to display resistance to
prion disease and no single case has so far been reported.7,8 Here, we describe
a case of a 9 week old male Rottweiler puppy presenting neurological deficits;
and histological examination revealed spongiform vacuolation characteristic of
those associated with prion diseases.9 Initial biochemical studies using
anti-PrP antibodies revealed the presence of partially proteinase K-resistant
fragment by western blotting. Furthermore, immunohistochemistry revealed
spongiform degeneration consistent with those found in prion disease and
displayed staining for PrPSc in the cortex.
Of major importance, PrPSc isolated from the Rottweiler was able to cross
the species barrier transmitted to hamster in vitro with PMCA and in vivo (one
hamster out of 5). Futhermore, second in vivo passage to hamsters, led to 100%
attack rate (n = 4) and animals displayed untypical lesional profile and shorter
incubation period.
In this study, we show that the canine species might be sensitive to prion
disease and that PrPSc isolated from a dog can be transmitted to dogs and
hamsters in vitro using PMCA and in vivo to hamsters.
If our preliminary results are confirmed, the proposal will have a major
impact on animal and public health and would certainly lead to implementing new
control measures for ‘canine spongiform encephalopathy’ (CSE).
References 1. Colchester AC, Colchester NT. The origin of bovine spongiform
encephalopathy: the human prion disease hypothesis. Lancet 2005; 366:856-61;
PMID:16139661; http://
dx.doi.org/10.1016/S0140-6736(05)67218-2.
2. Richt JA, Hall SM. BSE case associated with prion protein gene mutation.
PLoS Pathog 2008; 4:e1000156; PMID:18787697; http://dx.doi.org/10.1371/journal.
ppat.1000156.
3. Collinge J. Human prion diseases and bovine spongiform encephalopathy
(BSE). Hum Mol Genet 1997; 6:1699-705; PMID:9300662; http://dx.doi.org/10.1093/
hmg/6.10.1699.
4. Wyatt JM, Pearson GR, Smerdon TN, Gruffydd-Jones TJ, Wells GA, Wilesmith
JW. Naturally occurring scrapie-like spongiform encephalopathy in five domestic
cats. Vet Rec 1991; 129:233-6; PMID:1957458; http://dx.doi.org/10.1136/vr.129.11.233.
5. Jeffrey M, Wells GA. Spongiform encephalopathy in a nyala (Tragelaphus
angasi). Vet Pathol 1988; 25:398-9; PMID:3232315; http://dx.doi.org/10.1177/030098588802500514.
6. Kirkwood JK, Wells GA, Wilesmith JW, Cunningham AA, Jackson SI.
Spongiform encephalopathy in an arabian oryx (Oryx leucoryx) and a greater kudu
(Tragelaphus strepsiceros). Vet Rec 1990; 127:418-20; PMID:2264242.
7. Bartz JC, McKenzie DI, Bessen RA, Marsh RF, Aiken JM. Transmissible mink
encephalopathy species barrier effect between ferret and mink: PrP gene and
protein analysis. J Gen Virol 1994; 75:2947-53; PMID:7964604; http://dx.doi.org/10.1099/0022-1317-
75-11-2947.
8. Lysek DA, Schorn C, Nivon LG, Esteve-Moya V, Christen B, Calzolai L, et
al. Prion protein NMR structures of cats, dogs, pigs, and sheep. Proc Natl Acad
Sci U S A 2005; 102:640-5; PMID:15647367; http://dx.doi.org/10.1073/pnas.0408937102.
9. Budka H. Neuropathology of prion diseases. Br Med Bull 2003; 66:121-30;
PMID:14522854; http://dx.doi.org/10.1093/bmb/66.1.121.
Monday, March 26, 2012
CANINE SPONGIFORM ENCEPHALOPATHY: A NEW FORM OF ANIMAL PRION DISEASE
http://caninespongiformencephalopathy.blogspot.com/2012/03/canine-spongiform-encephalopathy-new.html
Monday, March 8, 2010
Canine Spongiform Encephalopathy aka MAD DOG DISEASE
Wednesday, October 17, 2012
Prion Remains Infectious after Passage through Digestive System of American
Crows (Corvus brachyrhynchos)
HUMANS
In conclusion, an analysis of dietary histories revealed statistical
associations between various meats/animal products and INCREASED RISK OF CJD.
When some account was taken of possible confounding, the association between
VEAL EATING AND RISK OF CJD EMERGED AS THE STRONGEST OF THESE ASSOCIATIONS
STATISTICALLY. ...
snip...
In the study in the USA, a range of foodstuffs were associated with an
increased risk of CJD, including liver consumption which was associated with an
apparent SIX-FOLD INCREASE IN THE RISK OF CJD. By comparing the data from 3
studies in relation to this particular dietary factor, the risk of liver
consumption became non-significant with an odds ratio of 1.2 (PERSONAL
COMMUNICATION, PROFESSOR A. HOFMAN. ERASMUS UNIVERSITY, ROTTERDAM). (???...TSS)
snip...see full report ;
Thursday, October 10, 2013
*************CJD REPORT 1994 increased risk for consumption of veal and
venison and lamb**************
CJD9/10022
October 1994
Mr R.N. Elmhirst Chairman British Deer Farmers Association Holly Lodge
Spencers Lane BerksWell Coventry CV7 7BZ
Dear Mr Elmhirst,
CREUTZFELDT-JAKOB DISEASE (CJD) SURVEILLANCE UNIT REPORT
Thank you for your recent letter concerning the publication of the third
annual report from the CJD Surveillance Unit. I am sorry that you are
dissatisfied with the way in which this report was published.
The Surveillance Unit is a completely independant outside body and the
Department of Health is committed to publishing their reports as soon as they
become available. In the circumstances it is not the practice to circulate the
report for comment since the findings of the report would not be amended. In
future we can ensure that the British Deer Farmers Association receives a copy
of the report in advance of publication.
The Chief Medical Officer has undertaken to keep the public fully informed
of the results of any research in respect of CJD. This report was entirely the
work of the unit and was produced completely independantly of the the
Department.
The statistical results reqarding the consumption of venison was put into
perspective in the body of the report and was not mentioned at all in the press
release. Media attention regarding this report was low key but gave a realistic
presentation of the statistical findings of the Unit. This approach to
publication was successful in that consumption of venison was highlighted only
once by the media ie. in the News at one television proqramme.
I believe that a further statement about the report, or indeed statistical
links between CJD and consumption of venison, would increase, and quite possibly
give damaging credence, to the whole issue. From the low key media reports of
which I am aware it seems unlikely that venison consumption will suffer
adversely, if at all.
http://web.archive.org/web/20030511010117/http://www.bseinquiry.gov.uk/files/yb/1994/10/00003001.pdf
Thursday, October 10, 2013
*** CJD REPORT 1994 increased risk for consumption of veal and venison and
lamb
PLUS, THE CDC DID NOT PUT THIS WARNING OUT FOR THE WELL BEING OF THE DEER
AND ELK ;
Thursday, May 26, 2011
Travel History, Hunting, and Venison Consumption Related to Prion Disease
Exposure, 2006-2007 FoodNet Population Survey Journal of the American Dietetic
Association Volume 111, Issue 6 , Pages 858-863, June 2011. http://transmissiblespongiformencephalopathy.blogspot.com/2011/05/travel-history-hunting-and-venison.html
NOR IS THE FDA recalling this CWD positive elk meat for the well being of
the dead elk ;
Wednesday, March 18, 2009
Noah's Ark Holding, LLC, Dawson, MN RECALL Elk products contain meat
derived from an elk confirmed to have CWD NV, CA, TX, CO, NY, UT, FL, OK RECALLS
AND FIELD CORRECTIONS: FOODS CLASS II
now, let’s see what the authors said about this casual link, personal
communications years ago. see where it is stated NO STRONG evidence. so, does
this mean there IS casual evidence ???? “Our conclusion stating that we found no
strong evidence of CWD transmission to humans”
From: TSS (216-119-163-189.ipset45.wt.net) Subject: CWD aka MAD DEER/ELK TO
HUMANS ???
Date: September 30, 2002 at 7:06 am PST From: "Belay, Ermias"
To: Cc: "Race, Richard (NIH)" ; ; "Belay, Ermias"
Sent: Monday, September 30, 2002 9:22 AM
Subject: RE: TO CDC AND NIH - PUB MED- 3 MORE DEATHS - CWD - YOUNG HUNTERS
Dear Sir/Madam,
In the Archives of Neurology you quoted (the abstract of which was attached
to your email), we did not say CWD in humans will present like variant CJD. That
assumption would be wrong. I encourage you to read the whole article and call me
if you have questions or need more clarification (phone: 404-639-3091). Also, we
do not claim that "no-one has ever been infected with prion disease from eating
venison." Our conclusion stating that we found no strong evidence of CWD
transmission to humans in the article you quoted or in any other forum is
limited to the patients we investigated.
Ermias Belay, M.D. Centers for Disease Control and Prevention
-----Original Message-----
From:
Sent: Sunday, September 29, 2002 10:15 AM
To: rr26k@nih.gov; rrace@niaid.nih.gov; ebb8@CDC.GOV
Subject: TO CDC AND NIH - PUB MED- 3 MORE DEATHS - CWD - YOUNG HUNTERS
Sunday, November 10, 2002 6:26 PM ......snip........end..............TSS
Thursday, April 03, 2008
A prion disease of cervids: Chronic wasting disease
2008 1: Vet Res. 2008 Apr 3;39(4):41 A prion disease of cervids: Chronic
wasting disease Sigurdson CJ.
snip...
*** twenty-seven CJD patients who regularly consumed venison were reported
to the Surveillance Center***,
snip... full text ;
*** These results would seem to suggest that CWD does indeed have zoonotic
potential, at least as judged by the compatibility of CWD prions and their human
PrPC target. Furthermore, extrapolation from this simple in vitro assay suggests
that if zoonotic CWD occurred, it would most likely effect those of the PRNP
codon 129-MM genotype and that the PrPres type would be similar to that found in
the most common subtype of sCJD (MM1).
*** The potential impact of prion diseases on human health was greatly
magnified by the recognition that interspecies transfer of BSE to humans by beef
ingestion resulted in vCJD. While changes in animal feed constituents and
slaughter practices appear to have curtailed vCJD, there is concern that CWD of
free-ranging deer and elk in the U.S. might also cross the species barrier.
Thus, consuming venison could be a source of human prion disease. Whether BSE
and CWD represent interspecies scrapie transfer or are newly arisen prion
diseases is unknown. Therefore, the possibility of transmission of prion disease
through other food animals cannot be ruled out. There is evidence that vCJD can
be transmitted through blood transfusion. There is likely a pool of unknown size
of asymptomatic individuals infected with vCJD, and there may be asymptomatic
individuals infected with the CWD equivalent. These circumstances represent a
potential threat to blood, blood products, and plasma supplies.
Wednesday, July 15, 2015
*** Additional BSE TSE prion testing detects pathologic lesion in unusual
brain location and PrPsc by PMCA only, how many cases have we missed? ***
re-TP&W Commission to address Chronic Wasting Disease
Wednesday, July 01, 2015
TEXAS Chronic Wasting Disease Detected in Medina County Captive Deer
Thursday, July 09, 2015
TEXAS Chronic Wasting Disease (CWD) Herd Plan for Trace-Forward Exposed
Herd with Testing of Exposed Animals
Tuesday, July 14, 2015
Texas Parks and Wildlife Commission Special Meeting Thursday on Chronic
Wasting Disease CWD
Wednesday, March 18, 2015
Chronic Wasting Disease CWD Confirmed Texas Trans Pecos March 18,
2015
Wednesday, March 25, 2015
Chronic Wasting Disease CWD Cases Confirmed In New Mexico 2013 and 2014
UPDATE 2015
Thursday, May 02, 2013
*** Chronic Wasting Disease (CWD) Texas Important Update on OBEX ONLY
TEXTING
Monday, February 11, 2013
TEXAS CHRONIC WASTING DISEASE CWD Four New Positives Found in Trans Pecos
Tuesday, July 10, 2012
Chronic Wasting Disease Detected in Far West Texas
Monday, March 26, 2012
Texas Prepares for Chronic Wasting Disease CWD Possibility in Far West
Texas
***for anyone interested, here is some history of CWD along the Texas, New
Mexico border, and my attempt to keep up with it...terry
snip...
see history CWD Texas, New Mexico Border ;
Monday, March 26, 2012
3 CASES OF CWD FOUND NEW MEXICO MULE DEER SEVERAL MILES FROM TEXAS BORDER
Sunday, October 04, 2009
CWD NEW MEXICO SPREADING SOUTH TO TEXAS 2009 2009 Summary of Chronic
Wasting Disease in New Mexico New Mexico Department of Game and Fish
Friday, May 22, 2015
*** Chronic Wasting Disease and Program Updates - 2014 NEUSAHA Annual
Meeting 12-14 May 2014
Sunday, July 12, 2015
*** Insights into CWD and BSE species barriers using real-time conversion
before cwd was discovered in Texas, Mr. Shannon Tomkins was a prolific
writer about cwd in other states, and a good one, but after cwd was discovered
in Texas, Mr. Shannon Tompkins seems to have gotten writers cramps. see his old
articles on CWD. I am aware Mr. Tompkins is everybody’s favorite outdoors
writer, and I have always enjoyed his outdoor writing and fishing reports. but
in my opinion, Mr. Tomkins and the Houston Chronicle have dropped the ball on
telling the readers and warning them about risk factors of the CWD TSE Prion, IN
TEXAS, years ago. ...
Thursday, October 30, 2014
A cool start to deer season, but challenges linger By Shannon
Tompkins
Saturday, November 23, 2013
TAHC REMINDS MULE DEER HUNTERS OF CWD TESTING REQUIREMENTS & CHECK
STATIONS November 22, 2013
Thursday, November 14, 2013
Deer don't disappoint after hunters' early optimism Houston Chronicle By
Shannon Tompkins November 13, 2013
CWD, Houston Chronicle, and CWD reporting, what happened ???
Thursday, December 27, 2012
CWD TSE PRION, dr. deer, shooting pen type game farms and ranchers, Texas,
TAHC, Houston Chronicle, all silent about disease ?
Thursday, December 13, 2012
HUNTERS FEELING THE HEAT Houston Chronicle December 13, 2012 OUTDOORS not
talking about CWD in Texas
Wednesday, November 07, 2012
Chronic Wasting Disease CWD, Texas, Houston Chronicle Shannon Thomkins 1998
- 2012 what happened ???
Thursday, July 12, 2012
CWD aka MAD DEER, ELK DISEASE TEXAS HOUSTON CHRONICLE Wednesday, July 11,
2012
CWD Herd Monitoring Program to be Enforced Jan. 2012 TEXAS
Greetings TAHC et al,
A kind greetings from Bacliff, Texas.
In reply to ;
Texas Animal Health Commission (TAHC) Announcement October 27, 2011
I kindly submit the following ;
Sunday, November 30, 2008
Commentary: Crimes hurt essence of hunting
Commentary on Houston Chronicle article [below] by Dr. Thomas Pringle
From: tom@cyber-dyne.com
Date: Fri, 10 May 2002 11:03:29 –0800
To: shannon.tompkins@chron.com
Subject: nice cwd reporting Shannon,
My compliments on these superb CWD Houston Chronical articles: not mincing
words, they display an excellent -- and most rare -- journalistic understanding
of the origin and continuing spread of CWD. (A couple of technical points were
not quite on target, see bottom.)
It is really refreshing to see in print the probable origin as sheep
scrapie-to-penned cervids in 1967 at Foothills Research Station, after decades
of relentless PR out of Colorado DOW seeking to distance itself from
responsibility (and liability). Facility workers at Colorado Dept of Wildlife
commented on the similarity to scrapie already in 1967 but never autopsied any
of their many dead research animals until 1979, discovering immediately an
obvious spongiform encephalopathy.
By that time of course, release to the wild and transfer of surplus animals
to zoos, game farms, and sister facilities had seeded widespread dissemination
of the disease. This was subsequently aggravated by the explosive growth in game
farms and intra- and inter-state cervid shipping, which at industry insistence
was in essence unregulated (eg regulated by state ag dept boosters). It is not
just the shoot-deer-in-a-barrel industry --elk velvet nutriceutical was never
tested by anyone for abnormal prions despite its troublesome composition (the
market collapsed from live CWD exported to Korea).
DOW itself did nothing to change its practises or control the disease until
very recently. Only last year, in the face of published evidence [below] that
the disease is expected to transfer to humans at the same low efficency as BSE
(129 human deaths to date), did they back off from encouraging human consumption
of venison from the endemic area. Nebraska fish and game even offered a
deer-neck stew recipe on its web site, even though spinal cord was long known to
have high infectious titres.
State fish and game depts are basically unfenced game farms. They have a
commercial concession that allows them earn a salary from sale of antler tags.
This motivates them to set up winter feeding stations, watering holes, salt
blocks, control predators, fight CWD testing, anything and everything that
increases numbers and leads to more or continued sales. Unfortunately, practises
leading to high cervid concentrations and testing avoidance are highly conducive
to the spread of CWD.
States such as Montana require testing of every game farm cervid dead for
any reason and an accounting of each animal's provenance and disposition; other
states adopt a "don't look, don't find" policy of testing avoidance with no
monitoring whatsoever of facilities. Absence of evidence is not evidence of
absence when it comes to TSEs. This disease just does not go away on its own, be
it kuru in New Guinea or scrapie in the US.
Given the numbers of Texas game farms, massive importation statistics, and
the high likelihood of trace-backs to affected facilities, it would be most
surprising if CWD were not already entrenched in Texas along the lines of
Wisconsin. It really questionable if stonewalling really is in the industry's
best interest -- who is going to hunt in a state that fears to test? The longer
infectious foci are allowed to operate, the greater the probability of multiple
introductions into wild deer. To ban imports (only after everyone has finished
importing all they want) just locks the barn door after the horse is long gone.
Half-measures on prion diseases are worse than no measures because they put
off the day of reckoning while exacerbating it immensely. Wisconsin's hasty
policy of culling 15,000 wild deer, yet business as usual (no testing, no
trace-backs, no inspection, no recordkeeping, no culls) at its sacrosanct 535
game farms. will result in CWD in perpetuity. The focus is on temporary
abatement for purposes of hunter reassurance. Dr. Charles Southwick
southwic@stripe.colorado.edu is a good source of scientific information on cwd
control strategies.
A few technical notes. First, the word mutation is reserved for genetic
change affecting DNA. It is not applicable to mere protein conformational
changes and fibril formation seen in amyloid diseases such as Alzheimer and CWD.
Mutation has been ruled out in CWD amplification. The prion gene of hundreds of
CWD and non-CWD animals have been sequenced by Dr. O'Rourke at Pullman. There is
no counterpart to the mutations that cause 15% of human CJD, much to the
disappointment of DOW.
No TSE has ever been seen in natural populations of any wild animal
anywhere in the world, making Colorado's story of a natural pocket (by
coincidence located adjacent to Foothills and Sybille research stations) a bit
far-fetched. Now by golly another natural pocket has flared up next to a game
farm in Wisconsin. How about the supposed natural pocket adjacent to the
massively infected game farm in the Black Hills -- despite its import history,
the industry PR firm in Ketchum turned this around 180 degrees -- now it's the
wild animals infecting innocent game farms!?! There has invariably been a nexus
to intensive livestock operations, be that cows fed rendered cows, mink farms
fed downer cows or deer quartered in a scrapie research facility.
Second, the "best available scientific evidence" upon which public policy
is normally based (more studies are needed, they always are, but something must
be used for the interim) is that published by Byron Caughey's group at Rocky Mtn
labs (after two years of delay by co-author Mike Miller of DOW who controlled
sample access). A proxy test was used since human volunteers cannot be
considered. Transmission efficiencies to human were similar to BSE -- low, but
hardly reassuring given England's experience.
Third, CWD has already been experimentally transferred to 6-7 species
including rodents, primates, and bovids, as published in peer-reviewed
scientific journals. The first round of transmission can be inefficient in TSEs;
after that, no species barrier. It is really the human-to-human second round
(plasma donation, childhood vaccines, cornea transplants) that has cause the
greatest consternation in England. A Ft. Collins hunter/blood donor with
preclinical cwd-induced CJD would have no idea he is ill.
It is currently impossible to test humans for cwd-induced CJD because there
is no known signature. Rises in baseline CJD cannot be monitored, contrary to
CDC, because of very large numbers of missed diagnoses, swings in ascertainment
effort, and diagnostic changes.
Best wishes and keep up the good work! Tom
Dr. Thomas Pringle Sperling Biomedical Foundation 3295 Kincaid St. Eugene,
OR 97405
CWD archives
2001
Mad cow disease: Could it be here?
Man's stubborn crusade attracts experts' notice By Carol Christian | August
5, 2001
Related Stories
• Mad cow's link to Beaumont death still uncertain
related_link|article-1563053|article-2042860|1 • Q&A: Risk of contracting
the disease 'extremely low' related_link|article-1487230|article-2042860|2 •
Assurances about mad cow risks not absolute
related_link|article-1477993|article-2042860|3 • Mad cow numbers
'extraordinarily low' related_link|article-1882572|article-2042860|4 •
Transfusion tied to 2nd case of mad cow illness in humans
related_link|article-1627999|article-2042860|5
Like Paul Revere with e-mail, Terry Singeltary Sr. is on a mission to sound
an alarm: Beware of mad cow disease.
As is true of many crusaders, however, his pleas often fall on deaf ears.
Health officials here and abroad insist that bovine spongiform encephalopathy --
popularly known as mad cow disease, a fatal brain disorder that can make cows
shake uncontrollably -- has been kept out of this country through surveillance
of the cattle industry.
But since his mother's death in December 1997, the Galveston County man has
been obsessed with possible connections between her deadly brain disorder,
sporadic Creutzfeldt-Jakob Disease, and mad cow disease.
And after much persistence on his part, people are taking notice of this
former machinist and high school dropout who jokes that he has a Ph.D. -- a Pool
Hall Degree.
"They called me Chicken Little for four years," he said. "Now they're
calling back, asking for more information."
For the past year he has been U.S. co-coordinator of an international
monitoring group called CJD Watch. He regularly gets e-mail from scientists and
journalists around the world.
Debora MacKenzie, a reporter for the British magazine New Scientist,
described Singeltary, 47, as a "dogged unearther and tabulator of government
documents."
Singeltary monitors "every word written about CJD/BSE," said Anita Manning
of USA Today, also by e-mail.
"He's passionate, opinionated and not always tactful, although I like him
because he's such a character and he is so transparent," Manning said. "He is
what he appears to be."
Science and environment writer Jonathan Leake of the Sunday Times in London
said Singeltary has helped him track down families of people with CJD along with
academic research papers.
"I strongly suspect he is right in thinking the USA has had BSE cases,"
Leake said by e-mail.
"The American government is making the same mistake as the British in
putting the short-term commercial interests of its farmers before health
considerations," he added.
"It should start formal and widespread testing of cattle plus compulsory
autopsies for all human CJD victims at the state's expense. If there is BSE,
then leaving it to spread will kill people -- and that would eventually destroy
the industry, too."
Texas Department of Health epidemiologist Julie Rawlings said Singeltary's
careful monitoring of the disease had proven useful.
"Terry has been helpful in providing contact information regarding suspect
CJD cases so that the Health Department can initiate case investigations and
learn more about CJD in Texas," she said.
Noting that the department cannot release records on individual patients,
she added, "I think we learn more from him than he does from us."
Mad cow disease surfaced in England in 1986 and quickly became an epidemic.
It since has been reported in 15 European countries, most recently Greece on
July 2, and the Czech Republic on June 14. Two German-born cows tested positive
for BSE in November.
Singeltary said he became convinced that BSE is here as he watched his
mother, Barbara Poulter of Crystal Beach, dying of sporadic Creutzfeldt-Jakob
Disease. The rare, fatal brain disease is sometimes accompanied by severe
jerking.
"She would jerk so bad at times, it would take three of us to hold her
down," Singeltary said. "They can call it whatever they want, but I know what I
saw, and what she went through. `Sporadic' simply means they don't know."
Poulter, a retired telephone-company field worker, had a form of sporadic
CJD -- Haidenhain variant -- that is even less common than the typical sporadic
case. One of its first symptoms is loss of vision.
She started seeing brown spots in September 1997 and was virtually blind
within two weeks. By the eighth week of the illness Poulter was bedridden, and
in the 10th week she died. Before that she had been in good health.
In many countries and most U.S. states, physicians are not required to
report CJD cases to health officials. Texas made the disease reportable in 1998.
Through 2000, there were 17 probable or confirmed cases, according to the Texas
Department of Health.
In mid-June, a case of sporadic CJD was confirmed through brain biopsy at
Christus Spohn Hospital Shoreline in Corpus Christi, said Jane Bakos, hospital
vice president. The patient has since died, the hospital reported.
CJD and mad cow disease leave their victims' brains full of holes like a
sponge. Although not contagious, the illnesses are thought to be transmissible
through prions, or nearly indestructible abnormal proteins.
Because the prion protein is not killed by standard sterilization, sporadic
CJD can be spread by contaminated surgical instruments.
In March 1996, the British government announced the discovery of a new
variant of CJD, most likely explained by exposure to bovine spongiform
encephalopathy.
Through June, 101 cases of new-variant CJD have been reported in the United
Kingdom, three in France and one in Ireland. In contrast to sporadic CJD, the
new variant usually affects younger patients and lasts longer.
No cases of new-variant CJD or BSE have been reported in the United States.
No relationship has been shown between sporadic CJD and mad cow disease.
There is no indication that new-variant CJD can be spread through blood
transfusions, but a U.S. Food and Drug Administration advisory committee voted
in June to broaden the categories for excluding potential donors. The
recommendations have not yet been approved by the FDA.
The American Red Cross has announced that on Sept. 17 it will begin
rejecting potential blood donors who, since 1980, have spent at least three
months in the United Kingdom or at least six months in any European country or
combination of countries. Those who have received a blood transfusion in Britain
since 1980 also will be rejected.
The primary collector of local blood donations is the Gulf Coast Regional
Blood Center, which will follow the FDA's guidelines, said Bill Teague,
president and chief executive officer.
Singeltary said it's naive to think that U.S. prevention efforts have kept
mad cow and new-variant CJD out of the United States.
"They haven't found it," he said, "because they haven't looked."
For one thing, he said, too few cows are tested for the disease. In the
first six months of this year, the European Union tested more than 3.2 million
cows, David Byrne of the European Commission said in a speech last month.
By contrast, it took the U.S. Department of Agriculture nearly 10 years to
analyze about 13,000 cow brains, according to the department's Web site.
With more than 68 million cattle slaughtered since 1990 in the United
States, according to the USDA, checking about 13,000 falls far short, Singeltary
said.
Though not a scholar, Singeltary has collected voluminous material on mad
cow and CJD. Disabled from a neck injury, Singeltary never used a computer until
1998. He now spends hours each day on the Internet while his wife, Bonnie
Singeltary, runs a flower shop in their home in Bacliff, in north Galveston
County.
His challenge to the CJD/BSE establishment is courageous and refreshing,
said Dr. Lynette Dumble, former visiting professor of surgery at University of
Texas Medical School at Houston and a former senior research fellow in the
history and philosophy of science at the University of Melbourne in
Australia.
"I certainly have no problem with Terry's ideas on BSE/CJD," said Dumble,
who coordinates the Global Sisterhood Network, a computer service that posts
media reports on developments affecting women. "His research skills are
excellent, and he is abreast of each and every development in the field."
Among Singeltary's worries now, he said, are widespread violations of an
August 1997 ban on feeding animal products to U.S. cattle. The FDA reported in
January that hundreds of feed manufacturers were not complying with regulations
designed to keep BSE out of this country.
(That same month, a Purina Mills feedlot near San Antonio told the FDA that
a "very low level" of cow parts had been found in cattle feed. The company
voluntarily removed 1,222 animals who had been fed the prohibited
materials.)
He obtained copies of FDA letters to various feed mills that had been found
in violation of the regulations and immediately sent them by e-mail to hundreds
of people around the world.
Singeltary might not be so zealous in getting the word out if he weren't
convinced that someone is covering up the truth.
"They used to say BSE would never transmit to humans," he said, "and it
has. They lied about the feed ban being in place.
"I've lost faith in the whole process. I've discovered too many things."
Tuesday, June 23, 2015
Report on the monitoring and testing of ruminants for the presence of
transmissible spongiform encephalopathies (TSEs) in the EU in 2013 Final version
18 May 2015
Transmissible Spongiform Encephalopthy TSE Prion Disease
*** Kuru Video
Kuru: The Science and The Sorcery
*** Scrapie Video
*** Human Mad Cow Video
*** USA sporadic CJD MAD COW DISEASE HAS HUGE PROBLEM Video
2014
***Moreover, L-BSE has been transmitted more easily to transgenic mice
overexpressing a human PrP [13,14] or to primates [15,16] than C-BSE.
***It has been suggested that some sporadic CJD subtypes in humans may
result from an exposure to the L-BSE agent.
*** Lending support to this hypothesis, pathological and biochemical
similarities have been observed between L-BSE and an sCJD subtype (MV genotype
at codon 129 of PRNP) [17], and between L-BSE infected non-human primate and
another sCJD subtype (MM genotype) [15].
snip...
Monday, October 10, 2011
EFSA Journal 2011 The European Response to BSE: A Success Story
snip...
EFSA and the European Centre for Disease Prevention and Control (ECDC)
recently delivered a scientific opinion on any possible epidemiological or
molecular association between TSEs in animals and humans (EFSA Panel on
Biological Hazards (BIOHAZ) and ECDC, 2011). This opinion confirmed Classical
BSE prions as the only TSE agents demonstrated to be zoonotic so far
*** but the possibility that a small proportion of human cases so far
classified as "sporadic" CJD are of zoonotic origin could not be excluded.
*** Moreover, transmission experiments to non-human primates suggest that
some TSE agents in addition to Classical BSE prions in cattle (namely L-type
Atypical BSE, Classical BSE in sheep, transmissible mink encephalopathy (TME)
and chronic wasting disease (CWD) agents) might have zoonotic potential.
snip...
Thursday, August 12, 2010
Seven main threats for the future linked to prions
First threat
The TSE road map defining the evolution of European policy for protection
against prion diseases is based on a certain numbers of hypotheses some of which
may turn out to be erroneous. In particular, a form of BSE (called atypical
Bovine Spongiform Encephalopathy), recently identified by systematic testing in
aged cattle without clinical signs, may be the origin of classical BSE and thus
potentially constitute a reservoir, which may be impossible to eradicate if a
sporadic origin is confirmed.
*** Also, a link is suspected between atypical BSE and some apparently
sporadic cases of Creutzfeldt-Jakob disease in humans.
*** These atypical BSE cases constitute an unforeseen first threat that
could sharply modify the European approach to prion diseases.
Second threat
snip...
Sunday, November 23, 2014
*** Confirmed Variant Creutzfeldt-Jakob Disease (variant CJD) Case in Texas
in June 2014 confirmed as USA case NOT European ***
Monday, November 3, 2014
USA CJD TSE PRION UNIT, TEXAS, SURVEILLANCE UPDATE NOVEMBER 2014
National Prion Disease Pathology Surveillance Center Cases Examined1
(October 7, 2014)
***6 Includes 11 cases in which the diagnosis is pending, and 19
inconclusive cases;
***7 Includes 12 (11 from 2014) cases with type determination pending in
which the diagnosis of vCJD has been excluded.
***The sporadic cases include 2660 cases of sporadic Creutzfeldt-Jakob
disease (sCJD),
***50 cases of Variably Protease-Sensitive Prionopathy (VPSPr)
***and 21 cases of sporadic Fatal Insomnia (sFI).
Thursday, January 15, 2015
41-year-old Navy Commander with sporadic Creutzfeldt–Jakob disease CJD TSE
Prion: Case Report
Subject: *** Becky Lockhart 46, Utah’s first female House speaker, dies
diagnosed with the extremely rare Creutzfeldt-Jakob disease aka mad cow type
disease
what is CJD ? just ask USDA inc., and the OIE, they are still feeding the
public and the media industry fed junk science that is 30 years old.
why doesn’t some of you try reading the facts, instead of rubber stamping
everything the USDA inc says.
sporadic CJD has now been linked to BSE aka mad cow disease, Scrapie, and
there is much concern now for CWD and risk factor for humans.
My sincere condolences to the family and friends of the House Speaker Becky
Lockhart. I am deeply saddened hear this.
with that said, with great respect, I must ask each and every one of you
Politicians that are so deeply saddened to hear of this needless death of the
Honorable House Speaker Becky Lockhart, really, cry me a friggen river. I am
seriously going to ask you all this...I have been diplomatic for about 17 years
and it has got no where. people are still dying. so, are you all stupid or
what??? how many more need to die ??? how much is global trade of beef and other
meat products that are not tested for the TSE prion disease, how much and how
many bodies is this market worth?
Saturday, January 17, 2015
*** Becky Lockhart 46, Utah’s first female House speaker, dies diagnosed
with the extremely rare Creutzfeldt-Jakob disease
*** ALERT new variant Creutzfeldt Jakob Disease nvCJD or vCJD, sporadic CJD
strains, TSE prion aka Mad Cow Disease United States of America Update December
14, 2014 Report ***
*** Creutzfeldt-Jakob Disease Public Health Crisis VIDEO
2015
O.05: Transmission of prions to primates after extended silent incubation
periods: Implications for BSE and scrapie risk assessment in human populations
Emmanuel Comoy, Jacqueline Mikol, Val erie Durand, Sophie Luccantoni,
Evelyne Correia, Nathalie Lescoutra, Capucine Dehen, and Jean-Philippe Deslys
Atomic Energy Commission; Fontenay-aux-Roses, France
Prion diseases (PD) are the unique neurodegenerative proteinopathies
reputed to be transmissible under field conditions since decades. The
transmission of Bovine Spongiform Encephalopathy (BSE) to humans evidenced that
an animal PD might be zoonotic under appropriate conditions. Contrarily, in the
absence of obvious (epidemiological or experimental) elements supporting a
transmission or genetic predispositions, PD, like the other proteinopathies, are
reputed to occur spontaneously (atpical animal prion strains, sporadic CJD
summing 80% of human prion cases). Non-human primate models provided the first
evidences supporting the transmissibiity of human prion strains and the zoonotic
potential of BSE. Among them, cynomolgus macaques brought major information for
BSE risk assessment for human health (Chen, 2014), according to their
phylogenetic proximity to humans and extended lifetime. We used this model to
assess the zoonotic potential of other animal PD from bovine, ovine and cervid
origins even after very long silent incubation periods. We recently observed the
direct transmission of a natural classical scrapie isolate to macaque after a
10-year silent incubation period, with features similar to some reported for
human cases of sporadic CJD, albeit requiring fourfold longe incubation than
BSE. Scrapie, as recently evoked in humanized mice (Cassard, 2014), is the third
potentially zoonotic PD (with BSE and L-type BSE), ***thus questioning the
origin of human sporadic cases. We will present an updated panorama of our
different transmission studies and discuss the implications of such extended
incubation periods on risk assessment of animal PD for human health.
===============
***thus questioning the origin of human sporadic cases...TSS
===============
O.08: H-type bovine spongiform encephalopathy associated with E211K prion
protein polymorphism: Clinical and pathologic features in wild-type and E211K
cattle following intracranial inoculation
S Jo Moore, M Heather West Greenlee, Jodi Smith, Eric Nicholson, Cathy
Vrentas, and Justin Greenlee United States Department of Agriculture; Ames, IA
USA
In 2006 an H-type bovine spongiform encephalopathy (BSE) case was reported
in an animal with an unusual polymorphism (E211K) in the prion protein gene.
Although the prevalence of this polymorphism is low, cattle carrying the K211
allele are predisposed to rapid onset of H-type BSE when exposed. The purpose of
this study was to investigate the phenotype of this BSE strain in wild-type
(E211E) and E211K heterozygous cattle. One calf carrying the wild-type allele
and one E211K calf were inoculated intracranially with H-type BSE brain
homogenate from the US 2006 case that also carried one K211 allelle. In
addition, one wild-type calf and one E211K calf were inoculated intracranially
with brain homogenate from a US 2003 classical BSE case. All animals succumbed
to clinical disease. Survival times for E211K H-type BSE inoculated catttle (10
and 18 months) were shorter than the classical BSE inoculated cattle (both 26
months). Significant changes in retinal function were observed in H-type BSE
challenged cattle only. Animals challenged with the same inoculum showed similar
severity and neuroanatomical distribution of vacuolation and disease-associated
prion protein deposition in the brain, though differences in neuropathology were
observed between E211K H-type BSE and classical BSE inoculated animals. Western
blot results for brain tissue from challenged animals were consistent with the
inoculum strains. ***This study demonstrates that the phenotype of E211K H-type
BSE remains stable when transmitted to cattle without the E211K polymorphism,
and exhibits a number of features that differ from classical BSE in both
wild-type and E211K cattle.
==============
***This study demonstrates that the phenotype of E211K H-type BSE remains
stable when transmitted to cattle without the E211K polymorphism, and exhibits a
number of features that differ from classical BSE in both wild-type and E211K
cattle.***
PLEASE SEE ;
Wednesday, May 27, 2015
BSE Case Associated with Prion Protein Gene Mutation
==============
P.108: Successful oral challenge of adult cattle with classical BSE
Sandor Dudas1,*, Kristina Santiago-Mateo1, Tammy Pickles1, Catherine
Graham2, and Stefanie Czub1 1Canadian Food Inspection Agency; NCAD Lethbridge;
Lethbridge, Alberta, Canada; 2Nova Scotia Department of Agriculture; Pathology
Laboratory; Truro, Nova Scotia, Canada
Classical Bovine spongiform encephalopathy (C-type BSE) is a feed- and
food-borne fatal neurological disease which can be orally transmitted to cattle
and humans. Due to the presence of contaminated milk replacer, it is generally
assumed that cattle become infected early in life as calves and then succumb to
disease as adults.
Here we challenged three 14 months old cattle per-orally with 100 grams of
C-type BSE brain to investigate age-related susceptibility or resistance. During
incubation, the animals were sampled monthly for blood and feces and subjected
to standardized testing to identify changes related to neurological
disease.
At 53 months post exposure, progressive signs of central nervous system
disease were observed in these 3 animals, and they were euthanized. Two of the
C-BSE animals tested strongly positive using standard BSE rapid tests, however
in 1 C-type challenged animal, Prion 2015 Poster Abstracts S67 PrPsc was not
detected using rapid tests for BSE. Subsequent testing resulted in the detection
of pathologic lesion in unusual brain location and PrPsc detection by PMCA
only.
Our study demonstrates susceptibility of adult cattle to oral transmission
of classical BSE. We are further examining explanations for the unusual disease
presentation in the third challenged animal.
========================
***Our study demonstrates susceptibility of adult cattle to oral
transmission of classical BSE. ***
P.86: Estimating the risk of transmission of BSE and scrapie to ruminants
and humans by protein misfolding cyclic amplification
Morikazu Imamura, Naoko Tabeta, Yoshifumi Iwamaru, and Yuichi Murayama
National Institute of Animal Health; Tsukuba, Japan
To assess the risk of the transmission of ruminant prions to ruminants and
humans at the molecular level, we investigated the ability of abnormal prion
protein (PrPSc) of typical and atypical BSEs (L-type and H-type) and typical
scrapie to convert normal prion protein (PrPC) from bovine, ovine, and human to
proteinase K-resistant PrPSc-like form (PrPres) using serial protein misfolding
cyclic amplification (PMCA).
Six rounds of serial PMCA was performed using 10% brain homogenates from
transgenic mice expressing bovine, ovine or human PrPC in combination with PrPSc
seed from typical and atypical BSE- or typical scrapie-infected brain
homogenates from native host species. In the conventional PMCA, the conversion
of PrPC to PrPres was observed only when the species of PrPC source and PrPSc
seed matched. However, in the PMCA with supplements (digitonin, synthetic polyA
and heparin), both bovine and ovine PrPC were converted by PrPSc from all tested
prion strains. On the other hand, human PrPC was converted by PrPSc from typical
and H-type BSE in this PMCA condition.
Although these results were not compatible with the previous reports
describing the lack of transmissibility of H-type BSE to ovine and human
transgenic mice, ***our findings suggest that possible transmission risk of
H-type BSE to sheep and human. Bioassay will be required to determine whether
the PMCA products are infectious to these animals.
================
***our findings suggest that possible transmission risk of H-type BSE to
sheep and human. ***
ALSO, PLEASE SEE ;
31 Jan 2015 at 20:14 GMT
*** Ruminant feed ban for cervids in the United States? ***
31 Jan 2015 at 20:14 GMT
Saturday, May 30, 2015
PRION 2015 ORAL AND POSTER CONGRESSIONAL ABSTRACTS
Saturday, December 13, 2014
Terry S. Singeltary Sr. Publications TSE prion disease
Diagnosis and Reporting of Creutzfeldt-Jakob Disease
Singeltary, Sr et al. JAMA.2001; 285: 733-734. Vol. 285 No. 6, February 14,
2001 JAMA
snip...
lost my mom to the Heidenhain Variant of Creutzfeldt Jakob Disease hvCJD
12/14/97 confirmed. I just made a promise to mom, never forget (I could never
ever forget what I saw), and never let them forget...
layperson
Terry S. Singeltary Sr., Bacliff, Texas USA 77518 flounder9@verizon.net
Rare report of deer disease in Texas causes stir, especially since it’s the
8 case of CWD documented in Texas, and the first case of CWD in Captive deer.
here is how I would have titled this article, and why.
Shannon Tompkins Finally Breaks Silence on Texas First Captive CWD Case and
Starts Off Spreading False Information About Risk Factors. ...
posted by Terry S. Singeltary Sr. at
9:43 AM
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