Medical Devices Containing Materials Derived from Animal Sources (Except
for In Vitro Diagnostic Devices) [Docket No. FDA–2013–D–1574]
Terry S. Singeltary Sr. Submission [Docket No. FDA–2013–D–1574]
Medical Devices Containing Materials Derived from Animal Sources (Except
for In Vitro Diagnostic Devices)
Draft Guidance for Industry and Food and Drug Administration Staff
DRAFT GUIDANCE
This guidance document is being distributed for comment purposes
only.
Document issued on January 23, 2014.
You should submit comments and suggestions regarding this draft guidance
document within 90 days of publication in the Federal Register of the notice
announcing the availability of the draft guidance. Submit written comments to
the Division of Dockets Management (HFA-305), Food and Drug Administration, 5630
Fishers Lane, rm. 1061, Rockville, MD 20852. Submit electronic comments to http://www.regulations.gov . Identify all
comments with the docket number listed in the notice of availability that
publishes in the Federal Register.
For questions regarding this document contact Dr. Charles Durfor at
301-796-6970 (charles.durfor@fda.hhs.gov) or Dr. Scott McNamee at 301-796-5523
or 301-796-5500 (scott.mcnamee@fda.hhs.gov).
This document, when final, will supersede “Medical Devices Containing
Materials Derived from Animal Sources (Except for In Vitro Diagnostic Devices)”
issued November 6, 1998.
U.S. Department of Health and Human Services
Food and Drug Administration
Center for Devices and Radiological Health
Transmissible Spongiform Encephalopathy Working Group
Office of Compliance
Office of Device Evaluation
Contains Nonbinding Recommendations
Preface
Additional Copies
Additional copies are available from the Internet. You may also send an
e-mail request to dsmica@fda.hhs.gov to receive an electronic copy of the
guidance or send a fax request to 301-847-8149 to receive a hard copy. Please
use the document number 2206 to identify the guidance you are requesting.
Contains Nonbinding Recommendations
Table of Contents
I.
Introduction.........................................................................................................................................................
1
II.
Background........................................................................................................................................................
1
III. Scope
................................................................................................................................................................
2
IV. Policy
Issues.....................................................................................................................................................
2
A. Control of Animal Tissue
Collection.............................................................................................................
2
B. Manufacturing Controls for Animal Tissue
Components..............................................................................
3
C.
Sterilization....................................................................................................................................................
3
D. Transmissible Spongiform Encephalopathy-Specific
Issues.........................................................................
4
V. References
........................................................................................................................................................
7
Contains Nonbinding Recommendations
Draft – Not for Implementation
1
Medical Devices Containing Materials Derived from Animal Sources (Except
for In Vitro Diagnostic Devices)
Draft Guidance for Industry and Food and Drug Administration Staff
This draft guidance, when finalized, will represent the Food and Drug
Administration's (FDA's) current thinking on this topic. It does not create or
confer any rights for or on any person and does not operate to bind FDA or the
public. You can use an alternative approach if the approach satisfies the
requirements of the applicable statutes and regulations. If you want to discuss
an alternative approach, contact the FDA staff responsible for implementing this
guidance. If you cannot identify the appropriate FDA staff, call the appropriate
number listed on the title page of this guidance.
I. Introduction
The Food and Drug Administration (FDA) is issuing this draft guidance to
update the policy regarding the use of animal-derived material in medical device
manufacturing. The role of animal derived-material in medical devices is well
established. However, these materials may carry a risk of transmitting
infectious disease when improperly collected, stored or manufactured. The
guidance describes the information you should document at the manufacturing
facility and include in any premarket submissions. This guidance, when
finalized, will supersede “Medical Devices Containing Materials Derived from
Animal Sources (Except for In Vitro Diagnostic Devices)” issued November 6, 1998
(the 1998 guidance).
FDA's guidance documents, including this guidance, do not establish legally
enforceable responsibilities. Instead, guidances describe the Agency's current
thinking on a topic and should be viewed only as recommendations, unless
specific regulatory or statutory requirements are cited. The use of the word
should in Agency guidances means that something is suggested or recommended, but
not required.
II. Background
This draft guidance updates the 1998 guidance by addressing aspects of
potential risk from the use of animal tissues (e.g., viruses and bacteria) and
now includes recommendations
Contains Nonbinding Recommendations
Draft – Not for Implementation
2
related to all transmissible spongiform encephalopathies (TSEs). The 1998
guidance addressed ways to reduce the potential for exposure to bovine
spongiform encephalopathy (BSE). This document continues to focus on the control
of transmissible disease, and contains recommendations for documenting the
source of animal tissue and conducting viral inactivation validation studies.
Commercial production of animals as the source of animal tissues used in medical
devices can introduce several kinds of risks. The 1998 document primarily
addressed geographical factors in the sourcing of the animal tissue. In addition
to geographical factors, this document includes recommendations that recognize
the role of careful animal husbandry to ensure safe tissue sources.
This guidance is intended to help you identify the possible risks related
to tissues from animal sources when these tissues are used in medical
devices.1
III. Scope
The information in this guidance is applicable to all medical devices that
contain or are exposed to animal-derived materials (e.g., bovine, ovine,
porcine, avian materials) with the exception of in vitro diagnostic devices.
Consideration of these issues should aid in reducing the risk of infectious
disease transmission by medical devices.
IV. Considerations When Using Animal-Derived Materials
A. Control of Animal Tissue Collection
FDA recommends you collect and document the following information for
animal tissue-derived materials that are used as either device components (e.g.,
pericardium, viscera, bone, hyaluronic acid, collagen) or manufacturing reagents
(e.g., tissue culture media, enzymes). You may document this information by
reference to other regulatory submissions (e.g., Master File, PMA, 510(k)) that
contain this information. Information that is helpful during the review of
animal-derived device materials includes Certificates of Analysis and Materials
Safety Data Sheets, when available. Regulatory submissions and facility records
(see 21 CFR 820.180) should describe the following:
• animal species;
• age of animal;
• specific tissue(s) used;
• animal country of origin and residence (more specific geographic location
when appropriate);
Contains Nonbinding Recommendations
Draft – Not for Implementation
3
• methods for monitoring the health of herd and the health of specific
animals from which tissues are collected (e.g., vaccinations with live modified
viruses that can co-purify in the desired tissue, active surveillance for human
pathogens);
• the United States Department of Agriculture (USDA) status of the
abattoir;
• methods and conditions for transporting animal tissue (e.g., tissue
refrigeration and quarantine); and
• procedures for maintaining records on the above cited issues should be
presented in regulatory submissions.
In addition, you should maintain records of the test results for any tests
described above for each lot of material at the manufacturing facility and
submitted in regulatory documents when appropriate.
B. Manufacturing Controls for Animal Tissue Components
FDA recommends you collect and document the information listed below for
all animal-derived materials (and facilities) used in device manufacture. As
stated previously, you may document this information by reference to other
regulatory submissions (e.g., Master File, PMA, 510(k)) and Certificates of
Analysis and Materials Safety Data Sheets, when available. Regulatory
submissions and facility records (Device Master Record, see 21 CFR 820.181)
should describe:
• test methods and release criteria permitting animal tissues to be further
processed and/or combined with other animal tissue(s) or device components for
manufacture;
• quarantine procedures for tissues until they have met/failed release
criteria;
• test methods and acceptance criteria for assessing in-process and final
product bioburden or sterility;
• methods for facility decontamination/sterilization so that
cross-contamination is avoided; and
• procedures for maintaining records of the above cited issues should be
provided in regulatory submissions.
You should maintain records of any test results for the tests described
above for each lot of material at the manufacturing facility (see Device History
Record (21 CFR 820.184)). When appropriate, you should also describe these
results in regulatory submissions. In addition, you should demonstrate and
validate manufacturing equipment cleaning, decontamination, and sterilization
relative to the specific pathogen exposure, and document the results.
C. Sterilization
Because the issues for validating the sterilization of devices containing
animal or human tissue are sufficiently complex to require a case by case
assessment, we recommend you review the
Contains Nonbinding Recommendations
Draft – Not for Implementation
4
FDA-recognized consensus standards listed in the References to this
guidance.2-8 Please note the extent of recognition of the current version of
standards referenced in this document on the FDA web site in the database
on
Recognized Consensus Standards (http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfStandards/search.cfm
). Enter the number of the Standard you wish to check into "Reference Number"
field. In addition, we recommend you contact the FDA staff responsible for
reviewing the specific device type to discuss your sterilization
procedures.
When the risk to the public health is a virus that may be part of the
animal tissue, we recommend that you consider the extent to which processing and
sterilization inactivate or remove the virus. FDA recommendations for validating
viral inactivation methods are described as follows:
Virus Validation Studies
You should assess the processing methods and sterilization techniques used
in product manufacture for their ability to inactivate and remove viruses.Viral
inactivation data are often obtained by determining the amount of virus in the
unprocessed source material before and after exposure to production and
sterilization processes.You may determine the extent to which viruses are
inactivated using scaled down versions of the specific production and
sterilization methods (e.g., acid extraction of collagen or dry heat
sterilization) using appropriate model viruses. If you use a model virus during
your viral inactivation study of your manufacturing and sterilization processes,
you should document the relevance of the model virus you use to the actual virus
present in the animal tissue (e.g., DNA-based or RNA-based, enveloped or
non-enveloped).
The results of your viral inactivation studies should demonstrate that the
sum of the log clearance of virus from the selected processing steps and
sterilization processes are at least six logs greater than the concentration of
virus anticipated in the unprocessed source material. While the design of viral
clearance studies should take the specific product and manufacturing methods
into consideration, insight into the general design of such studies is possible
via review of the referenced guidance documents.9,10 Viral inactivation studies
do not address reduction of possible prion contamination.
D. Transmissible Spongiform Encephalopathy-Specific Issues
The Food and Drug Administration may issue rules specifically on Bovine
Spongiform Encephalopathy (BSE) and the regulation of medical devices. Any final
rule on BSE would take precedence over the recommendations of this guidance
document. Current issues regarding BSE may be addressed at the following FDA
website: http://www.fda.gov/animalveterinary/guidancecomplianceenforcement/complianceenforcement/bovinespongiformencephalopathy/default.htm
BSE is a degenerative disease that affects the central nervous system of
cattle and is similar to other transmissible spongiform encephalopathies (TSEs)
found in sheep (scrapie), deer
Contains Nonbinding Recommendations
Draft – Not for Implementation
5
(chronic wasting disease),11 and humans (Creutzfeldt-Jakob Disease or CJD).
Current data suggest that the incubation period of 2 to 8 years after exposure
is required before BSE symptoms are detectable. Currently, there are no
treatments for TSE diseases and no screening tests for the detection of disease
in a live animal or man. Diagnosis is achieved by post-mortem microscopic
examination of brain tissue, as well as assays using ELISA and Western Blot
techniques.
The BSE infectious agent is widely theorized to be a prion, (i.e., an
abnormally folded form of a normal cellular protein) that facilitates the
conversion of additional normal cellular proteins to the infectious prion
structure (PrP(res)). Infectious PrP(res) has been detected in bovine brain,
spinal cord, eye, ileum, lymph nodes, proximal colon, spleen, tonsil, dura
mater, pineal gland, placenta, cerebrospinal fluid, pituitary, adrenal, distal
colon, nasal mucosa, peripheral nerves, bone marrow, liver, lung, pancreas,
thymus.12 The detection of TSE-infection in other tissues may occur in the
future when data are available from more sensitive assays or larger animal
studies. Transmission has been experimentally demonstrated in animal studies. 13
The TSE agent is also known to be extremely resistant to traditional forms of
disinfection and sterilization.
Epidemiologic data suggest that the BSE epidemic in Great Britain began in
1986 by feeding cattle contaminated meat and bone meal as their protein source.
According to the World Organization for Animal Health (OIE), as of 2011, 184619
BSE cases have been identified in Britain and twenty-two cases have been
detected in North American cattle. As of 2011, there were also 221 definite or
probable cases of new variant CJD (vCJD) worldwide, which is the human form of
BSE that appears to be transmitted by consumption of BSE-tainted beef.14 Since
December 2003, four cases of Creutzfeldt-Jakob disease (vCJD) presumed to be
transfusion-related vCJD have been reported.15 Epidemiological data is updated
periodically and is available at http://www.hpa.org.uk/Topics/InfectiousDiseases/InfectionsAZ/CreutzfeldtJakobDisease/EpidemiologicalData/.
Given the long incubation time for disease onset, the absence of a
screening test for live animals, and vCJD’s fatal outcome, we recommend that you
collect and document the following information for any material derived from an
animal (e.g. cattle, sheep, goats, cervids such as deer and elk, etc.) with the
potential to carry TSE infection:
• animal species;
• specific tissue used (if multiple tissues are used, identify all tissues
used);
• animal’s country of origin and country of residence (or a more specific
geographic information when appropriate);
• methods for actively monitoring the health of herd and the health of
specific animals from which tissues are collected;
• information concerning the long term health of the herd (e.g., documented
breeding history, animal traceability, absence of TSE disease, and standard
vaccinations such as live modified viruses which could co-purify in the desired
tissue);
Contains Nonbinding Recommendations
Draft – Not for Implementation
6
• the frequency and type of veterinarian inspections;
• animal feed composition (e.g., animal feed history records, including
recordation of co-mingling of feeds, and, labeling of animal feed composition at
distribution locations) (In 2008, FDA issued a rule prohibiting certain material
from being fed to ruminants. The rule may be found at http://www.gpo.gov/fdsys/pkg/FR-2008-04-25/html/08-1180.htm);
• USDA status of the abattoir;
• animal age at sacrifice;
• animal sacrifice methods that reduce the risk of cross contaminating
non-TSE tissues with material from tissues that could contain TSE;
• specifics of the pre and/or post mortem inspections (e.g., gross visual
inspection, specific organs and anomalies exams, lab tests such as PrP
testing);
• tests performed (and release criteria) for permitting tissue to be
further processed and/or combined with other tissues and device components
(e.g., a Certificate of Analysis); and
• methods for maintaining the records associated with the above cited
issues should be provided in regulatory submissions.
You should maintain records of the test results for tests listed above for
each lot of material at the manufacturing facility (see Device History Record
(21 CFR 820.184)). When appropriate, you should also describe these results in
regulatory submissions.
In addition, the residence time of TSE-infectious material on surfaces is
unknown and methods to completely assure removal of TSE-infectious material from
surfaces have yet to be fully understood. Products developed for use in
abattoirs and non-manufacturing sites where surface contamination by materials
from potentially TSE-infected animals (cattle, sheep, cervids such as deer and
elk, etc.) may occur may not have been studied or validated for use on more
critical sites or equipment such as those intended for the manufacture of
devices from animal tissue. Therefore, in facilities involved in device
manufacture using tissue from potentially TSE-infected animals (cattle, sheep,
cervids such as deer and elk, etc.) your documentation should identify
when/whether any potentially TSE-infected material may have been previously
processed in your facility and what steps you have taken to address any
potential contamination. This information could include the information
previously discussed under “Manufacturing Controls for Animal Tissue Components”
in section IV. B. of this guidance and the dates of previous tissue processing
(see also 21 CFR 820.50).
Because screening assays that can ensure TSE-free bovine tissues have not
been FDA-approved or introduced into general practice, the methods discussed
above (e.g., monitoring animal feed, controlling animal husbandry and tissue
handling) reflect the best available approaches for preparing safe medical
devices from bovine tissue. However, when a TSE-screening assay is validated to
accurately identify TSE-contaminated tissues, FDA will consider revising this
guidance as appropriate and recommending that such a test be introduced into the
standard operating procedures for bovine tissue collection and processing.
Contains Nonbinding Recommendations
Draft – Not for Implementation
7
V. References
1. January 3, 2003 letter from David W. Feigal, MD to Manufacturers of
FDA-Regulated Medical Devices Containing Animal Tissue Products or Components
available at http://www.fda.gov/ohrms/dockets/ac/04/briefing/4019B2_12.pdf
2. AAMI ANSI ISO 11135:2007 - Sterilization of health care products -
Ethylene oxide - Part 1: Requirements for the development, validation, and
routine control of a sterilization process for medical devices
3. AAMI ANSI ISO 17665-1:2006 - Sterilization of health care products --
Moist heat -- Part 1: Requirements for the development, validation, and routine
control of a sterilization process for medical devices
4. AAMI ANSI ISO 11137-1:2006/(R) 2010 - Sterilization of health care
products - Radiation - Part 1: Requirements for development, validation, and
routine control of a sterilization process for medical devices
5. AAMI ANSI ISO 11737-1:2006 (R)2011 - Sterilization of medical devices -
Microbiological methods Part 1: Determination of the population of
microorganisms on product
6. AAMI ANSI ISO 11737-2:2009 - Sterilization of medical devices --
Microbiological methods -- Part 2: Tests of sterility performed in the
definition, validation and maintenance of a sterilization process
7. AAMI ANSI ISO 14160:2011 - Sterilization of health care products -
Liquid chemical sterilizing agents for single-use medical devices utilizing
animal tissues and their derivatives - Requirements for characterization,
development, validation and routine control of a sterilization process for
medical devices
8. AAMI ANSI ISO 14937:2009 - Sterilization of health care products -
General requirements for characterization of a sterilizing agent and the
development, validation, and routine control of a sterilization process for
medical devices
9. “ICH Viral Safety Document: QSA Viral Safety Evaluation of Biotechnology
Products Derived from Cell Lines of Human or Animal Origin (63 FR 51074,
September 24, 1998)” http://www.fda.gov/downloads/RegulatoryInformation/Guidances/UCM129101.pdf
10. “Viral Safety Evaluation of Biotechnology Products derived from Cell
Lines of Human or Animal Origin” 35 USP <1050>
11. The web site for the USDA’s Animal and Plant Health and Inspection
Services concerning CWD (Chronic Wasting Disease) is
Contains Nonbinding Recommendations
Draft – Not for Implementation
8
12. WHO Tables on Tissue Infectivity Distribution in Transmissible
Spongiform Encephalopathies, http://www.who.int/bloodproducts/tablestissueinfectivity.pdf
13. “Experimental interspecies transmission studies of the transmissible
spongiform encephalopathies to cattle comparison to bovine spongiform
encephalopathy in cattle” Cutlip, et.al., Journal of Veterinary Diagnostic
Investigation May 2011 vol. 23 no. 3 407-420
14. "Transmissible Spongiform Encephalopathies Advisory Committee Meeting
Presentation: vCJD World Situation and Updates” by RG Will (August 1,
2011)
15. Incidence of variant Creutzfeldt-Jakob disease diagnoses and deaths in
the UK compiled by N J Andrews at the Statistics Unit, Centre for Infections,
Health Protection Agency. (updated 18th May 2011, http://www.cjd.ed.ac.uk/)
Draft Guidance for Industry and Staff; Availability: Medical Devices
Containing Materials Derived From Animal Sources (Except for In Vitro Diagnostic
Devices), 3826–3827 [2014–01232]
DEPARTMENT OF HEALTH AND HUMAN SERVICES
Food and Drug Administration
[Docket No. FDA–2013–D–1574]
Medical Devices Containing Materials Derived From Animal Sources (Except
for In Vitro Diagnostic Devices); Draft Guidance for Industry and Food and Drug
Administration Staff; Availability
AGENCY: Food and Drug Administration, HHS.
ACTION: Notice.
*** BSE--U.S. 50 STATE CONFERENCE CALL Jan. 9, 2001 ***
Subject: BSE--U.S. 50 STATE CONFERENCE CALL Jan. 9, 2001
Date: Tue, 9 Jan 2001 16:49:00 –0800
From: "Terry S. Singeltary Sr." flounder@wt.net
Reply-To: Bovine Spongiform Encephalopathy BSE-L@uni-karlsruhe.de
To: BSE-L@uni-karlsruhe.de
######### Bovine Spongiform Encephalopathy
#########
Greetings List Members,
I was lucky enough to sit in on this BSE conference call today and even
managed to ask a question. that is when the trouble started.
I submitted a version of my notes to Sandra Blakeslee of the New York
Times, whom seemed very upset, and rightly so.
"They tell me it is a closed meeting and they will release whatever
information they deem fit. Rather infuriating."
and i would have been doing just fine, until i asked my question. i was
surprised my time to ask a question so quick.
(understand, these are taken from my notes for now. the spelling of names
and such could be off.)
[host Richard Barns] and now a question from Terry S. Singeltary of CJD
Watch.
[TSS] yes, thank you, U.S. cattle, what kind of guarantee can you give for
serum or tissue donor herds?
[no answer, you could hear in the back ground, mumbling and 'we can't. have
him ask the question again.]
[host Richard] could you repeat the question?
[TSS] U.S. cattle, what kind of guarantee can you give for serum or tissue
donor herds?
[not sure whom ask this] what group are you with?
[TSS] CJD Watch, my Mom died from hvCJD and we are tracking CJD world-wide.
[not sure who is speaking] could you please disconnect Mr. Singeltary
[TSS] you are not going to answer my question?
[not sure whom speaking] NO
from this point, i was still connected, got to listen and tape the whole
conference. at one point someone came on, a woman, and ask again;
[unknown woman] what group are you with?
[TSS] CJD Watch and my Mom died from hvCJD we are trying to tract down CJD
and other human TSE's world wide. i was invited to sit in on this from someone
inside the USDA/APHIS and that is why i am here. do you intend on banning me
from this conference now?
at this point the conference was turned back up, and i got to finish
listening. They never answered or even addressed my one question, or even
addressed the issue. BUT, i will try and give you a run-down for now, of the
conference.
IF i were another Country, I would take heed to my notes, BUT PLEASE do not
depend on them. ask for transcript from;
RBARNS@ORA.FDA.GOV 301-827-6906
he would be glad to give you one ;-)
Rockville Maryland, Richard Barns Host
BSE issues in the U.S., How they were labelling ruminant feed? Revising
issues.
The conference opened up with the explaining of the U.K. BSE epidemic
winding down with about 30 cases a week.
although new cases in other countries were now appearing.
Look at Germany whom said NO BSE and now have BSE.
BSE increasing across Europe.
Because of Temporary Ban on certain rendered product, heightened interest
in U.S.
A recent statement in Washington Post, said the New Administration (old GW)
has a list of issues. BSE is one of the issues.
BSE Risk is still low, minimal in U.S. with a greater interest in MBM not
to enter U.S.
HOWEVER, if BSE were to enter the U.S. it would be economically disastrous
to the render, feed, cattle, industries, and for human health.
(human health-they just threw that in cause i was listening. I will now jot
down some figures in which they told you, 'no need to write them down'. just
hope i have them correct. hmmm, maybe i hope i don't ???)
80% inspection of rendering
*Problem-Complete coverage of rendering HAS NOT occurred.
sizeable number of 1st time FAILED INITIAL INSPECTION, have not been
reinspected (70% to 80%).
Compliance critical, Compliance poor in U.K. and other European Firms.
Gloria Dunason Major Assignment 1998 goal TOTAL compliance. This _did not_
occur. Mixed level of compliance, depending on firm.
Rendering FDA license and NON FDA license
system in place for home rendering & feed 76% in compliance 79% cross
contamination 21% DID NOT have system 92% record keeping less than 60% total
compliance
279 inspectors 185 handling prohibited materials
Renderer at top of pyramid, significant part of compliance. 84% compliance
failed to have caution statement render 72% compliance & cross
contamination caution statement on feed, 'DO NOT FEED TO CATTLE'
56 FIRMS NEVER INSPECTED
1240 FDA license feed mills 846 inspected
"close to 400 feed mills have not been inspected"
80% compliance for feed.
10% don't have system.
NON-FDA licensed mills There is NO inventory on non licensed mills.
approximately 6000 to 8000 Firms ??? 4,344 ever inspected. "FDA does not have a
lot of experience with"
40% do NOT have caution statement 'DO NOT FEED'.
74% Commingling compliance
"This industry needs a lot of work and only half gotten to"
"700 Firms that were falitive, and need to be re-inspected, in addition to
the 8,000 Firms."
Quote to do BSE inspection in 19 states by end of January or 30 days, and
other states 60 days. to change feed status??? Contract check and ask questions
and pass info.
At this time, we will take questions.
[I was about the third or fourth to ask question. then all B.S.eee broke
loose, and i lost my train of thought for a few minutes. picked back up here]
someone asking about nutritional supplements and sourcing, did not get
name. something about inspectors not knowing of BSE risk??? the conference
person assuring that Steve Follum? and the TSE advisory Committee were handling
that.
Some other Dr. Vet, whom were asking questions that did not know what to
do???
[Dennis Wilson] California Food Agr. Imports, are they looking at imports?
[Conference person] they are looking at imports, FDA issued imports
Bulletin.
[Linda Singeltary ??? this was a another phone in question, not related i
don't think] Why do we have non-licensed facilities?
(conference person) other feed mills do not handle as potent drugs???
Dennis Blank, Ken Jackson licensed 400 non FDA 4400 inspected of a total of
6000 to 8000,
(they really don't know how many non licensed Firms in U.S. they guess 6000
to 8000??? TSS)
Linda Detwiler asking everyone (me) not to use emergency BSE number, unless
last resort. (i thought of calling them today, and reporting the whole damn U.S.
cattle herd ;-) 'not'
Warren-Maryland Dept. Agr. Prudent to re-inspect after 3 years. concerned
of Firms that have changed owners.
THE END
TSS
############ http://mailhost.rz.uni-karlsruhe.de/warc/bse-l.html
############
FROM New York TIMES
Subject: Re: BSE 50 STATE CONFERENCE CALL thread from BSE List and FDA
Posting of cut version...
Date: Thu, 11 Jan 2001 22:02:47 -0700 From: "Sandy Blakeslee" sblakeslee@mindspring.com
To: "Terry S. Singeltary Sr." References: 1
Hi terry -- thanks for all your help. I know it made a difference with the
FDA getting out that release.
----- Original Message -----
From: "Terry S. Singeltary Sr." flounder@wt.net
Sent: Thursday, January 11, 2001 2:06 PM
Subject: BSE 50 STATE CONFERENCE CALL thread from BSE List and FDA Posting
of cut version...
> > hi sandy,
>From the New York Times NYTimes.com, January 11, 2001
Many Makers of Feed Fail to Heed Rules on Mad Cow Disease By SANDRA
BLAKESLEE
Large numbers of companies involved in manufacturing animal feed are not
complying with regulations meant to prevent the emergence and spread of mad cow
disease in the United States, the Food and Drug Administration said yesterday.
The widespread failure of companies to follow the regulations, adopted in
August 1997, does not mean that the American food supply is unsafe, Dr. Stephen
Sundlof, director of the Center for Veterinary Medicine at the F.D.A., said in
an interview.
But much more needs to be done to ensure that mad cow disease does not
arise in this country, Dr. Sundlof said.
The regulations state that feed manufacturers and companies that render
slaughtered animals into useful products generally may not feed mammals to
cud-chewing animals, or ruminants, which can carry mad cow disease.
All products that contain rendered cattle or sheep must have a label that
says, "Do not feed to ruminants," Dr. Sundlof said. Manufacturers must also have
a system to prevent ruminant products from being commingled with other rendered
material like that from chicken, fish or pork. Finally, all companies must keep
records of where their products originated and where they were sold.
Under the regulations, F.D.A. district offices and state veterinary offices
were required to inspect all rendering plants and feed mills to make sure
companies complied. But results issued yesterday demonstrate that more than
three years later, different segments of the feed industry show varying levels
of compliance.
Among 180 large companies that render cattle and another ruminant, sheep,
nearly a quarter were not properly labeling their products and did not have a
system to prevent commingling, the F.D.A. said. And among 347 F.D.A.-licensed
feed mills that handle ruminant materials - these tend to be large operators
that mix drugs into their products - 20 percent were not using labels with the
required caution statement, and 25 percent did not have a system to prevent
commingling.
Then there are some 6,000 to 8,000 feed mills so small they do not require
F.D.A. licenses. They are nonetheless subject to the regulations, and of 1,593
small feed producers that handle ruminant material and have been inspected, 40
percent were not using approved labels and 25 percent had no system in place to
prevent commingling.
On the other hand, fewer than 10 percent of companies, big and small, were
failing to comply with the record-keeping regulations.
The American Feed Industry Association in Arlington, Va., did not return
phone calls seeking comment.
Subject: USDA/APHIS response to BSE-L--U.S. 50 STATE CONFERENCE CALL Jan.
9, 2001
Date: Wed, 10 Jan 2001 14:04:21 –0500
From: "Gomez, Thomas M." tmg1@CDC.GOV
Reply-To: Bovine Spongiform Encephalopathy BSE-L@uni-karlsruhe.de
To: BSE-L@uni-karlsruhe.de
######### Bovine Spongiform Encephalopathy
#########
USDA/APHIS would like to provide clarification on the following point from
Mr. Singeltary's 9 Jan posting regarding the 50 state conference call.
[Linda Detwiler asking everyone (me) not to use emergency BSE number,
unless last resort. (i thought of calling them today, and reporting the whole
damn U.S. cattle herd ;-) 'not']
Dr. Detwiler was responding to an announcement made during the call to use
the FDA emergency number if anyone wanted to report a cow with signs suspect for
BSE. Mr. Singeltary is correct that Dr. Detwiler asked participants to use the
FDA emergency number as a last resort to report cattle suspect for BSE. What Mr.
Singeltary failed to do was provide the List with Dr. Detwiler's entire
statement. Surveillance for BSE in the United States is a cooperative effort
between states, producers, private veterinarians, veterinary hospitals and the
USDA. The system has been in place for over 10 years. Each state has a system in
place wherein cases are reported to either the State Veterinarian, the federal
Veterinarian in Charge or through the veterinary diagnostic laboratory system.
The states also have provisions with emergency numbers. Dr. Detwiler asked
participants to use the systems currently in place to avoid the possibility of a
BSE-suspect report falling through the cracks. Use of the FDA emergency number
has not been established as a means to report diseased cattle of any nature.
############ http://mailhost.rz.uni-karlsruhe.de/warc/bse-l.html
############
Subject: Re: USDA/APHIS response to BSE-L--U.S. 50 STATE CONFERENCE CALL
Jan.9, 2001
Date: Wed, 10 Jan 2001 13:44:49 -0800 From: "Terry S. Singeltary Sr." flounder@wt.net
Reply-To: Bovine Spongiform Encephalopathy BSE-L@uni-karlsruhe.de
To: BSE-L@uni-karlsruhe.de References: 1
######### Bovine Spongiform Encephalopathy
#########
Hello Mr. Thomas,
> What Mr. Singeltary failed to do was provide > the List with Dr.
Detwiler's entire statement.
would you and the USDA/APHIS be so kind as to supply this list with a full
text version of the conference call and or post on your web-site? if so when,
and thank you. if not, why not?
> The system has been in place for over 10 years.
that seems to be a very long time for a system to be in place, and only
test 10,700 cattle from some 1.5 BILLION head (including calf crop). Especially
since French are testing some 20,000 weekly and the E.U. as a whole, are testing
many many more than the U.S., with less cattle, same risk of BSE/TSEs.
Why does the U.S. insist on not doing massive testing with the tests which
the E.U. are using? Why is this, please explain?
Please tell me why my question was not answered?
> U.S. cattle, what kind of guarantee can you > give for serum or
tissue donor herds?
It was a very simple question, a very important question, one that
pertained to the topic of BSE/feed, and asked in a very diplomatic way. why was
it not answered?
If all these years, we have been hearing that pharmaceutical grade bovines
were raised for pharmaceuticals vaccines etc. But yet the USA cannot comply with
feed regulations of the ruminant feed ban, PLUS cannot even comply with the
proper labelling of the feed, cross contamination etc. Then how in the world can
you Guarantee the feed fed to pharmaceutical grade bovine, were actually non
ruminant feed?
Before i was ask to be 'disconnected', i did hear someone in the background
say 'we can't'-- have him ask the question again.
could you please be so kind, as to answer these questions?
thank you, Terry S. Singeltary Sr. Bacliff, Texas USA
P.S. if you will also notice, i did not post that emergency phone number
and do not intend on passing it on to anyone. I was joking when i said i should
call and report the whole damn U.S. Herd. So please pass that on to Dr.
Detwiler, so she can rest easily.
BUT, they should be reported, some are infected with TSE. The U.S. is just
acting as stupid as Germany and other Countries that insist they are free of
BSE.
TSS
Subject: Report on the assessment of the Georgraphical BSE-risk of the USA
July 2000 (not good)
Date: Wed, 17 Jan 2001 21:23:51 -0800 From: "Terry S. Singeltary Sr." flounder@wt.net
Reply-To: Bovine Spongiform Encephalopathy BSE-L@uni-karlsruhe.de
To: BSE-L@uni-karlsruhe.de
######### Bovine Spongiform Encephalopathy
#########
Greetings List Members and ALL EU Countries,
Because of this report, and the recent findings of the 50-state BSE
Conference call, I respectfully seriously suggest that these Countries and the
SSC re-evaluate the U.S.A. G.B.R. to a risk factor of #3.
I attempted to post this to list in full text, but would not accept...
thank you, kind regards, Terry S. Singeltary Sr., Bacliff, Texas USA
Report on the assessment of the Geographical BSE-risk of the USA July 2000
PART II
REPORT ON THE ASSESSMENT OF THE GEOGRAPHICAL BSE RISK OF THE UNITED STATES
OF AMERICA
- 29 -
Report on the assessment of the Geographical BSE-risk of the USA July 2000
EXECUTIVE SUMMARY
OVERALL ASSESSMENT
The current geographical BSE-risk (GBR) level is II, i.e. it is unlikely
but cannot be excluded that domestic cattle are (clinically or pre-clinically)
infected with the BSE-agent.
Stability: Before 1990 the system was extremely unstable because feeding of
MBM to cattle happened, rendering was inappropriate with regard to deactivation
of the BSE-agent and SRM and fallen stock were rendered for feed. From 1990 to
1997 it improved to very unstable, thanks to efforts undertaken to trace
imported animals and exclude them from the feed chain and intensive
surveillance. In 1998 the system became neutrally stable after the RMBM-ban of
1997.
External challenges: A moderate external challenge occurred in the period
before 1990 because of importation of live animals from BSE-affected countries,
in particular from the UK and Ireland. It cannot be excluded that some
BSE-infected animals have been imported by this route and did enter the US
rendering and feed production system. The efforts undertaken since 1990 to trace
back UK-imported cattle and to exclude them from the feed chain reduced the
impact of the external challenge significantly.
Interaction of external challenges and stability: While extremely unstable,
the US system was exposed to a moderate external challenge, mainly resulting
from cattle imports from the UK. It can not be excluded that BSE-infectivity
entered the country by this route and has been recycled to domestic cattle. The
resulting domestic cases would have been processed while the system was still
very unstable or unstable and would hence have initiated a number of second or
third generation cases. However, the level of the possible domestic prevalence
must be below the low detection level of the surveillance in place.
As long as there are no changes in stability or challenge the probability
of cattle to be (pre-clinically or clinically) infected with the BSE-agent will
remain at the current level.
JUSTIFICATION
1. DATA
The available information was suitable to carry out the GBR risk
assessment.
- 30 -
Report on the assessment of the Geographical BSE-risk of the USA July 2000
2. STABILITY
2.1 Overall appreciation of the ability to identify BSE-cases and to
eliminate animals at risk of being infected before they are processed
· Before 1989, the ability of the system to identify (and eliminate) BSE
cases was limited. · Since 1990 this ability is significantly improved, thanks
to a good BSE-surveillance and culling system (contingency plan). · Today the
surveillance should be able to detect clinical BSE-cases within the limits set
by an essential passive surveillance system, i.e. some cases might remain
undetected.
2.2 Overall appreciation of the ability to avoid recycling BSE-infectivity,
should it enter processing
· Before 1997 the US rendering and feed producing system would not have
been able to avoid recycling of the BSE agent to any measurable extent. If the
BSE-agent was introduced the feed chain, it could probably have reached cattle.
· After the introduction of the RMBM-to-ruminants-ban in August 1997 the ability
of the system to avoid recycling of BSE-infectivity was somewhat increased. It
is still rather low due to the rendering system of ruminant material (including
SRM and fallen stock) and the persisting potential for cross-contamination of
cattle feed with other feeds and hence RMBM.
2.3 Overall assessment of the Stability
· Until 1990 the US BSE/cattle system was extremely unstable as RMBM was
commonly fed to cattle, the rendering system was not able to reduce
BSE-infectivity and SRM were rendered. This means that incoming BSE infectivity
would have been most probably recycled to cattle and amplified and the disease
propagated. · Between 1990 and 1995 improvements in the BSE surveillance and the
efforts to trace back and remove imported cattle gradually improved the
stability but the system remained very unstable. In 1998 the system became
unstable because of an RMBM-ban introduced in 1997. After 1998 the ban was fully
implemented and the system is regarded to be neutrally stable since 1998. The US
system is therefore seen to neither be able to amplify nor to reduce circulating
or incoming BSE-infectivity.
3. CHALLENGES
A moderate external challenge occurred in the period 1980-1989 because of
importation of live animals from the UK. imports from other countries are
regarded to have been negligible challenges. · As a consequence of this external
challenge, infectivity could have entered the feed cycle and domestic animals
could have been exposed to the agent. These domestic BSE-incubating animals
might have again entered processing, leading to an internal challenge since
1991. · This internal challenge could have produced domestic cases of BSE, yet
prevalence levels could have been below the detection limits of the surveillance
system until now. (According to US calculations, the current surveillance
-31 -
Report on the assessment of the Geographical BSE-risk of the USA July 2000
system could detect clinical incidence of 1-3 cases per year per million
adult cattle, i.e. in absolute numbers 43-129 cases per year). Between 1990 und
1995, with the exclusion of the imported animals from Europe from the feed
chain, the effect of the external challenges decreased.
4. CONCLUSION ON THE RESULTING RISKS
4.1 Interaction of stability and challenqe
· In the late 80s, early 90s a moderate external challenges met an
extremely unstable system. This would have amplified the incoming
BSE-infectivity and propagated the disease. · With the exclusion of the imported
animals from Europe from the feed chain between 1990 and 1995 the effect of the
external challenge decreased. · Before 1998 an internal challenge, if it
developed, would have met a still unstable system (inappropriate rendering, no
SRM ban, RMBM ban only after 1997) and the BSE-infectivity could have been
recycled and amplified. · After 1998 the neutrally stable system could still
recycle the BSE-agent but due to the RMBM-ban of 1997 the BSE-infectivity
circulating in the system would probably not be amplified.
4.2 Risk that BSE-infectivity enters processing
· A very low processing risk developed in the late 80s when the UK-imports
were slaughtered or died. It increased until 1990 because of the higher risk to
be infected with BSE of cattle imported from the UK in 1988/89, as these animals
could have been processed prior to the back-tracing of the UK-imports in 1990. ·
From 1990 to 1995 a combination of surviving non-traced UK imports and some
domestic (pre-)clinical cases could have arrived at processing resulting in an
assumed constant low but non-negligible processing risk. · After 1995 any
processing risk relates to assumed domestic cases arriving at processing. · The
fact that no domestic cases have been shown-up in the BSE-surveillance is
reassuring - it indicates that BSE is in fact not present in the country at
levels above the detection limits of the country's surveillance system. This
detection level has been calculated according to US-experts to be between 1
& 3 clinical cases per million adult cattle per year.
Note: The high turnover in parts of the dairy cattle population with a
young age at slaughter makes it unlikely that fully developed clinical cases
would occur (and could be detected) or enter processing. However, the
theoretical infective load of the pre-clinical BSE-cases that under this
scenario could be processed, can be assumed to remain relatively low.
4.3 Risk that BSE-infectivity is recycled and propagated
· During the period covered by this assessment (1980-1999) the US-system
was not able to prevent propagation of BSE should it have entered, even if this
ability was significantly improved with the MBM-ban of 1997. · However, since
the likelihood that BSE-infectivity entered the system is regarded to be small
but non-negligible, the risk that propagation of the disease took place is also
small but not negligible.
- 32 -
Report on the assessment of the Geographical BSE-risk of the USA July 2000
5. CONCLUSION ON THE GEOGRAPHICAL BSE-RISK
5.1 The current GBR
The current geographical BSE-risk (GBR) level is II, i.e. it is unlikely
but cannot be excluded that domestic cattle are (clinically or pre-clinically)
infected with the BSE-agent.
5.2 The expected development of the GBR
As long as there are no changes in stability or challenge the probability
of cattle to be (pre-clinically or clinically) infected with the BSE-agent
remains at the current level.
5.3 Recommendations for influencin.q the future GBR
· As long as the stability of the US system is not significantly enbanced
above neutral levels it remains critically important to avoid any new external
challenges. · All measures that would improve the stability of the system, in
particular with regard to its ability to avoid recycling of the BSE-agent should
it be present in the cattle population, would reduce, over time, the probability
that cattle could be infected with the BSE-agent. Possible actions include:
removal of SRMs and/or fallen stock from rendering, better rendering processes,
improved compliance with the MBM-ban including control and reduction of
cross-contamination. · Results from an improved intensive surveillance
programme, targeting at risk sub-populations such as adult cattle in fallen
stock or in emergency slaughter, could verify the current assessment.
snip...
end...tss
U.S.A. 50 STATE BSE MAD COW CONFERENCE CALL Jan.
9, 2001
FDA Singeltary
submission 2001
Greetings again Dr. Freas and Committee Members, I wish to submit the
following information to the Scientific Advisors and Consultants Staff 2001
Advisory Committee (short version). I understand the reason of having to shorten
my submission, but only hope that you add it to a copy of the long version, for
members to take and read at their pleasure, (if cost is problem, bill me,
address below). So when they realize some time in the near future of the 'real'
risks i speak of from human/animal TSEs and blood/surgical products. I cannot
explain the 'real' risk of this in 5 or 10 minutes at some meeting, or on 2 or 3
pages, but will attempt here:
snip...see full text ;
-----Original
Message-----
From: Terry S.
Singeltary Sr. [mailto:flounder@wt.net]
Sent: Tuesday, February
18, 2003 12:45 PM
To: Freas, William Cc:
Langford, Sheila
Subject: Re:
re-vCJD/blood and meeting of Feb. 20, 2003 Greetings FDA, Variant
Creutzfeldt-Jakob Disease Guidance Topic of Feb. 20 TSE Cmte. [Committee Meeting
on February 20, 2003] FDA’s Transmissible Spongiform Encephalopathies Advisory
Committee will meet Feb. 20 to hear updates on the implementation of the
agency’s variant Creutzfeldt-Jakob Disease guidance and its effect on blood
supply.
FULL SUBMISSION ;
Docket Management Docket: 02D-0073 - Guidance: Validation of Procedures for
Processing of Human Tissues Intended for Transplantation Comment Number: EC -4
Accepted - Volume 1
2003-01-16 16:33:04 http://www.fda.gov/ohrms/dockets/dailys/03/Jan03/012403/8004bdfc.html
Docket: 02D-0073 - Guidance: Validation of Procedures for Processing of
Human Tissues Intended for Transplantation Greetings, please be advised; with
the new findings from Collinge et al; that BSE transmission to the
129-methionine genotype can lead to an alternate phenotype which is
indistinguishable from type 2 PrPSc, the commonest sporadic CJD, i only ponder
how many of the sporadic CJDs in the USA are tied to this alternate phenotype?
these new findings are very serious, and should have a major impact on the way
sporadic CJDs are now treated as opposed to the vCJD that was thought to be the
only TSE tied to ingesting beef, in the medical/surgical arena. these new
findings should have a major impact on the way sporadic CJD is ignored, and
should now be moved to the forefront of research as with vCJD/nvCJD.
SNIP...FULL TEXT ;
Subject: [Docket No. FSIS-2006-0011] FSIS Harvard Risk Assessment of Bovine
Spongiform Encephalopathy (BSE)
Singeltary submission ;
FSIS, USDA, REPLY TO SINGELTARY
Animal and Plant Health Inspection Service (APHIS) Proposed Rule: Bovine
Spongiform Encephalopathy; Minimal-Risk Regions; Importation of Live Bovines and
Products Derived From Bovines
2014
Wednesday, January 01, 2014
Molecular Barriers to Zoonotic Transmission of Prions
*** chronic wasting disease, there was no absolute barrier to conversion of
the human prion protein.
*** Furthermore, the form of human PrPres produced in this in vitro assay
when seeded with CWD, resembles that found in the most common human prion
disease, namely sCJD of the MM1 subtype.
Subtype 1: (sCJDMM1 and sCJDMV1)
This subtype is observed in patients who are MM homozygous or MV
heterozygous at codon 129 of the PrP gene (PRNP) and carry PrPSc Type 1.
Clinical duration is short, 3‑4 months.32 The most common presentation in
sCJDMM1 patients is cognitive impairment leading to frank dementia, gait or limb
ataxia, myoclonic jerks and visual signs leading to cortical blindness
(Heidenhain’s syndrome)...
Animals injected with iatrogenic Creutzfeldt–Jakob disease MM1 and genetic
Creutzfeldt–Jakob disease MM1 linked to the E200K mutation showed the same
phenotypic features as those infected with sporadic Creutzfeldt–Jakob disease
MM1 prions...
*** our results raise the possibility that CJD cases classified as VV1 may
include cases caused by iatrogenic transmission of sCJD-MM1 prions or food-borne
infection by type 1 prions from animals, e.g., chronic wasting disease prions in
cervid. In fact, two CJD-VV1 patients who hunted deer or consumed venison have
been reported (40, 41). The results of the present study emphasize the need for
traceback studies and careful re-examination of the biochemical properties of
sCJD-VV1 prions. ***
snip...see full text ;
Wednesday, June 16, 2010
Defining sporadic Creutzfeldt-Jakob disease strains and their transmission
properties
The epidemiological findings in sCJD demonstrate that approximately 80% of
patients are diagnosed with “classic CJD” types MM1 and MV1, which might
intriguingly suggest an infectious rather than genetic origin for the majority
of sCJD cases.
snip...
Therefore if sCJD(MV2) and sCJD(VV2) were to become iatrogenic sources of
human infection, the host response may be indistinguishable from sCJD(MM1) and
more transmissible with respect to further infection.
END...TSS
Monday, December 02, 2013
*** A parliamentary inquiry has been launched today into the safety of
blood, tissue and organ screening following fears that vCJD – the human form of
‘mad cow’ disease – may be being spread by medical procedures
Wednesday, December 11, 2013
Detection of Infectivity in Blood of Persons with Variant and Sporadic
Creutzfeldt-Jakob Disease
Friday, November 22, 2013
Chronic Wasting disease CWD is threat to the entire UK deer population
Singeltary submission to the Scottish Parliament
Thursday, January 2, 2014
CWD TSE Prion in cervids to hTGmice, Heidenhain Variant Creutzfeldt-Jacob
Disease MM1 genotype, and iatrogenic CJD ???
Tuesday, March 5, 2013
*** Use of Materials Derived From Cattle in Human Food and Cosmetics;
Reopening of the Comment Period FDA-2004-N-0188-0051 (TSS SUBMISSION)
FDA believes current regulation protects the public from BSE but reopens
comment period due to new studies
Friday, January 17, 2014
Annual report of the Scientific Network on BSE-TSE EFSA, Question No
EFSA-Q-2013-01004, approved on 11 December 2013
TECHNICAL REPORT
Sunday, December 15, 2013
*** FDA PART 589 -- SUBSTANCES PROHIBITED FROM USE IN ANIMAL FOOD OR FEED
VIOLATIONS OFFICIAL ACTION INDICATED OAI UPDATE DECEMBER 2013 UPDATE
Saturday, December 21, 2013
**** Complementary studies detecting classical bovine spongiform
encephalopathy infectivity in jejunum, ileum and ileocaecal junction in
incubating cattle ****
Saturday, November 16, 2013
Management of neurosurgical instruments and patients exposed to
creutzfeldt-jakob disease 2013 December
Infect Control Hosp Epidemiol.
Thursday, November 14, 2013
Prion diseases in humans: Oral and dental implications
Saturday, November 2, 2013
Recommendation of the Swiss Expert Committee for Biosafety on the
classification of activities using prion genes and prion protein January 2013
Friday, August 16, 2013
*** Creutzfeldt-Jakob disease (CJD) biannual update August 2013 U.K. and
Contaminated blood products induce a highly atypical prion disease devoid of
PrPres in primates
WHAT about the sporadic CJD TSE proteins ?
WE now know that some cases of sporadic CJD are linked to atypical BSE and
atypical Scrapie, so why are not MORE concerned about the sporadic CJD, and all
it’s sub-types $$$
Creutzfeldt-Jakob Disease CJD cases rising North America updated report
August 2013
*** Creutzfeldt-Jakob Disease CJD cases rising North America with Canada
seeing an extreme increase of 48% between 2008 and 2010 ***
Sunday, October 13, 2013
*** CJD TSE Prion Disease Cases in Texas by Year, 2003-2012
Thursday, January 2, 2014
*** CWD TSE Prion in cervids to hTGmice, Heidenhain Variant Creutzfeldt-Jacob Disease MM1 genotype, and iatrogenic CJD ??? http://transmissiblespongiformencephalopathy.blogspot.com/2014/01/cwd-tse-prion-in-cervids-to-htgmice.html
Friday, January 10, 2014
*** vpspr, sgss, sffi, TSE, an iatrogenic by-product of gss, ffi, familial type prion disease, what it ??? http://transmissiblespongiformencephalopathy.blogspot.com/2014/01/vpspr-sgss-sffi-tse-iatrogenic-by.html
*** vpspr, sgss, sffi, TSE, an iatrogenic by-product of gss, ffi, familial type prion disease, what it ??? http://transmissiblespongiformencephalopathy.blogspot.com/2014/01/vpspr-sgss-sffi-tse-iatrogenic-by.html
Monday, January 13, 2014
*** Prions in Variably Protease-Sensitive Prionopathy: An Update Pathogens 2013
Pathogens 2013, 2, 457-471; doi:10.3390/pathogens2030457http://prionopathy.blogspot.com/2014/01/prions-in-variably-protease-sensitive.html
*** Prions in Variably Protease-Sensitive Prionopathy: An Update Pathogens 2013
Pathogens 2013, 2, 457-471; doi:10.3390/pathogens2030457http://prionopathy.blogspot.com/2014/01/prions-in-variably-protease-sensitive.html
Wednesday, January 15, 2014
*** INFECTION PREVENTION AND CONTROL OF CJD, VCJD AND OTHER HUMAN PRION DISEASES IN HEALTHCARE AND COMMUNITY SETTINGS Variably Protease-Sensitive Prionopathy (VPSPr) January 15, 2014http://transmissiblespongiformencephalopathy.blogspot.com/2014/01/infection-prevention-and-control-of-cjd.html
*** INFECTION PREVENTION AND CONTROL OF CJD, VCJD AND OTHER HUMAN PRION DISEASES IN HEALTHCARE AND COMMUNITY SETTINGS Variably Protease-Sensitive Prionopathy (VPSPr) January 15, 2014http://transmissiblespongiformencephalopathy.blogspot.com/2014/01/infection-prevention-and-control-of-cjd.html
Sunday, January 19, 2014
*** National Prion Disease Pathology Surveillance Center Cases Examined1 as
of January 8, 2014 ***
Terry S. Singeltary Sr.
P.O. Box 42
Bacliff, Texas USA 77518
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