Effect of autolysis on the specificity of bovine spongiform encephalopathy rapid tests
Daniela Meloni*, Katia Varello, Marzia Pezzolato, Elsa Manzardo, Maria C. Cavarretta, Francesco Ingravalle, Maria Caramelli, Elena Bozzetta National Reference Laboratory for Animal Encephalopathies, Istituto Zooprofilattico Sperimentale del Piemonte Liguria e Valle d’Aosta, Turin, Italy. *Corresponding author Email addresses: DM: daniela.meloni@izsto.it KV: katia.varello@izsto.it MP: marzia.pezzolato@izsto.it EM: elsa.manzardo@izsto.it MCC: test.rapidi@izsto.it FI: francesco.ingravalle@izsto.it MC: maria.caramelli@izsto.it EB: elena.bozzetta@izsto.it
Abstract
Background: Routine rapid testing for Bovine Spongiform Encephalopathy (BSE) has highlighted some problems with BSE rapid test performance, the most significant being the number of initially reactive samples and the false positive results on autolyzed tissue. This point is important for BSE active surveillance in risk populations, because tissue autolysis is often unavoidable in routine cases. A robust test suitable for use on field material is therefore needed. To date, very limited information regarding the effect of autolysis on the robustness of rapid tests has been documented; therefore, the National Reference Centre for Animal Encephalopathies (CEA) rapid test laboratory selected 450 autolyzed and negative brain stem samples from fallen stock bovines older than 24 months to assess the specificity of four tests approved for BSE active surveillance: Biorad TeSeE, Enfer TSE version 2.0, Prionics® Check LIA, and IDEXX Herd Check BSE Antigen Kit EIA. The samples were graded according to the degree of autolysis and then dissected into five portions, four of which randomly assigned to processing by rapid tests and one to be available for confirmatory Western blot analysis. Findings: the specificity of the four systems was 100% for all three grades of autolysis, while the percentage of initially reactive results was 0.00 (95%CI 0.00-0.82), 0.22 (95%CI 0.006-1.23), 0.44 (95%CI 0.05-1.60), and 0.89 (95%CI 0.24-2.26) for the Biorad TeSeE, the Prionics® Check LIA, the IDEXX Herd Check BSE and the Enfer TSE tests, respectively. No association with degree of autolysis could be drawn. Conclusions: the present study demonstrates that the four rapid tests can be considered wellrunning diagnostic tools regardless of tissue quality; nevertheless, the number of initial reactive samples reported for some systems must not be underestimated in routine testing. Furthermore the compliance with the reported performance can be guaranteed only when an ongoing high careful batch quality control system is in place.
http://www.biomedcentral.com/content/pdf/1756-0500-3-193.pdf
Here in the USA, the USDA et al likes to take samples of suspect BSE mad cows that are either perfectly healthy cows, OR, they let the suspect samples sit, and deteriorate, until valid testing on that tissue sample is impossible. Seems that is the only way they can keep their 'gold card'. ...TSS
"I would note that the sample was taken in April, at which time the protocols allowed for a preservative to be used. The sample was not submitted to us until last week because the veterinarian set aside the sample after preserving it and simply forgot to send it in.
http://www.usda.gov/wps/portal/usdahome?contentidonly=true&contentid=2005/07/0280.xml
Executive Summary
In June 2005, an inconclusive bovine spongiform encephalopathy (BSE) sample from November 2004, that had originally been classified as negative on the immunohistochemistry test, was confirmed positive on SAF immunoblot (Western blot). The U.S. Department of Agriculture (USDA) identified the herd of origin for the index cow in Texas; that identification was confirmed by DNA analysis. USDA, in close cooperation with the Texas Animal Health Commission (TAHC), established an incident command post (ICP) and began response activities according to USDA’s BSE Response Plan of September 2004. Response personnel removed at-risk cattle and cattle of interest (COI) from the index herd, euthanized them, and tested them for BSE; all were negative. USDA and the State extensively traced all at-risk cattle and COI that left the index herd. The majority of these animals entered rendering and/or slaughter channels well before the investigation began. USDA’s response to the Texas finding was thorough and effective.
http://www.aphis.usda.gov/lpa/issues/bse/epi-updates/bse_final_epidemiology_report.pdf
Report on Food & Drug Administration Dallas District Investigation of Bovine Spongiform Encephalopathy Event in Texas 2005
Executive Summary:
On June 24, 2005, USDA informed FDA that a cow in Texas tested positive for Bovine Spongiform Encephalopathy (BSE). Information provided by APHIS was that the BSE positive cow was born and raised in a herd in Texas and was approximately 12 years old. The animal was sampled for BSE at a pet food plant in Texas on November 15, 2004, as part of USDA’s enhanced surveillance program.
http://www.fda.gov/cvm/texasfeedrpt.htm
Texas even had a 'secret' test that showed that mad cow positive;
experimental IHC test results, because the test was
not a validated procedure, and because the two
approved IHC tests came back negative, the results
were not considered to be of regulatory significance
and therefore were not reported beyond the
laboratory.
• A Western blot test conducted the week of
June 5, 2005, returned positive for BSE.
http://www.usda.gov/documents/vs_bse_ihctestvar.pdf
48 hr BSE confirmation turnaround took 7+ months to confirm this case, so the BSE MRR policy could be put into place. ...TSS
THIS highly suspect stumbling and staggering Texas Mad Cow got not test at all, went straight to render ;
FOR IMMEDIATE RELEASE Statement May 4, 2004 Media Inquiries: 301-827-6242 Consumer Inquiries: 888-INFO-FDA
Statement on Texas Cow With Central Nervous System Symptoms On Friday, April 30 th , the Food and Drug Administration learned that a cow with central nervous system symptoms had been killed and shipped to a processor for rendering into animal protein for use in animal feed.
FDA, which is responsible for the safety of animal feed, immediately began an investigation. On Friday and throughout the weekend, FDA investigators inspected the slaughterhouse, the rendering facility, the farm where the animal came from, and the processor that initially received the cow from the slaughterhouse.
FDA's investigation showed that the animal in question had already been rendered into "meat and bone meal" (a type of protein animal feed). Over the weekend FDA was able to track down all the implicated material. That material is being held by the firm, which is cooperating fully with FDA.
Cattle with central nervous system symptoms are of particular interest because cattle with bovine spongiform encephalopathy or BSE, also known as "mad cow disease," can exhibit such symptoms. In this case, there is no way now to test for BSE. But even if the cow had BSE, FDA's animal feed rule would prohibit the feeding of its rendered protein to other ruminant animals (e.g., cows, goats, sheep, bison).
FDA is sending a letter to the firm summarizing its findings and informing the firm that FDA will not object to use of this material in swine feed only. If it is not used in swine feed, this material will be destroyed. Pigs have been shown not to be susceptible to BSE. If the firm agrees to use the material for swine feed only, FDA will track the material all the way through the supply chain from the processor to the farm to ensure that the feed is properly monitored and used only as feed for pigs.
To protect the U.S. against BSE, FDA works to keep certain mammalian protein out of animal feed for cattle and other ruminant animals. FDA established its animal feed rule in 1997 after the BSE epidemic in the U.K. showed that the disease spreads by feeding infected ruminant protein to cattle.
Under the current regulation, the material from this Texas cow is not allowed in feed for cattle or other ruminant animals. FDA's action specifying that the material go only into swine feed means also that it will not be fed to poultry.
FDA is committed to protecting the U.S. from BSE and collaborates closely with the U.S. Department of Agriculture on all BSE issues. The animal feed rule provides crucial protection against the spread of BSE, but it is only one of several such firewalls. FDA will soon be improving the animal feed rule, to make this strong system even stronger.
####
http://www.fda.gov/bbs/topics/news/2004/NEW01061.html
OR, there were some 9,200 samples where testing used the least likely test to find BSE, the IHC ;
National Veterinary Services Laboratory (NVSL) Immunohistochemistry (IHC) Testing Summary
The BSE enhanced surveillance program involves the use of a rapid screening test, followed by confirmatory testing for any samples that come back "inconclusive." The weekly summary below captures all rapid tests conducted as part of the enhanced surveillance effort. It should be noted that since the enhanced surveillance program began, USDA has also conducted approximately 9,200 routine IHC tests on samples that did not first undergo rapid testing. This was done to ensure that samples inappropriate for the rapid screen test were still tested, and also to monitor and improve upon IHC testing protocols. Of those 9,200 routine tests, one test returned a non-definitive result on July 27, 2005. That sample underwent additional testing at NVSL, as well as at the Veterinary Laboratories Agency in Weybridge, England, and results were negative. To view the IHC testing numbers from 1990 through 2004, click on the following link:
http://www.aphis.usda.gov/lpa/issues/bse/surveillance/figure2f.html
http://www.aphis.usda.gov/lpa/issues/bse_testing/test_results.html
BSE test options were limited
USDA: In 9,200 cases only one type of test could be used
WASHINGTON (AP)--The U.S. Department of Agriculture acknowledged Aug. 17 that its testing options for bovine spongiform encephalopathy were limited in 9,200 cases despite its effort to expand surveillance throughout the U.S. herd.
In those cases, only one type of test was used--one that failed to detect the disease in an infected Texas cow.
The department posted the information on its website because of an inquiry from The Associated Press.
Conducted over the past 14 months, the tests have not been included in the department's running tally of BSE tests since last summer. That total reached 439,126 on Aug. 17.
"There's no secret program," the department's chief veterinarian, John Clifford, said in an interview. "There has been no hiding, I can assure you of that."
Officials intended to report the tests later in an annual report, Clifford said.
These 9,200 cases were different because brain tissue samples were preserved with formalin, which makes them suitable for only one type of test--immunohistochemistry, or IHC.
In the Texas case, officials had declared the cow free of disease in November after an IHC test came back negative. The department's inspector general ordered an additional kind of test, which confirmed the animal was infected.
Veterinarians in remote locations have used the preservative on tissue to keep it from degrading on its way to the department's laboratory in Ames, Iowa. Officials this year asked veterinarians to stop using preservative and send fresh or chilled samples within 48 hours.
The department recently investigated a possible case of BSE that turned up in a preserved sample. Further testing ruled out the disease two weeks ago.
Scientists used two additional tests--rapid screening and Western blot--to help detect BSE in the country's second confirmed case, in a Texas cow in June. They used IHC and Western blot to confirm the first case, in a Washington state cow in December 2003.
"The IHC test is still an excellent test," Clifford said. "These are not simple tests, either."
Clifford pointed out that scientists reran the IHC several times and got conflicting results. That happened, too, with the Western blot test. Both tests are accepted by international animal health officials.
Date: 8/25/05
http://www.hpj.com/archives/2005/aug05/aug29/BSEtestoptionswerelimited.cfm
Office of the United States Attorney District of Arizona
FOR IMMEDIATE RELEASE For Information Contact Public Affairs
February 16, 2007 WYN HORNBUCKLE Telephone: (602) 514-7625 Cell: (602) 525-2681
CORPORATION AND ITS PRESIDENT PLEAD GUILTY TO DEFRAUDING GOVERNMENT’S MAD COW DISEASE SURVEILLANCE PROGRAM
PHOENIX -- Farm Fresh Meats, Inc. and Roland Emerson Farabee, 55, of Maricopa, Arizona, pleaded guilty to stealing $390,000 in government funds, mail fraud and wire fraud, in federal district court in Phoenix.U.S. Attorney Daniel Knauss stated, “The integrity of the system that tests for mad cow disease relies upon the honest cooperation of enterprises like Farm Fresh Meats. Without that honest cooperation, consumers both in the U.S. and internationally are at risk. We want to thank the USDA’s Office of Inspector General for their continuing efforts to safeguard the public health and enforce the law.” Farm Fresh Meats and Farabee were charged by Information with theft of government funds, mail fraud and wire fraud. According to the Information, on June 7, 2004, Farabee, on behalf of Farm Fresh Meats, signed a contract with the U.S. Department of Agriculture (the “USDA Agreement”) to collect obex samples from cattle at high risk of mad cow disease (the “Targeted Cattle Population”). The Targeted Cattle Population consisted of the following cattle: cattle over thirty months of age; nonambulatory cattle; cattle exhibiting signs of central nervous system disorders; cattle exhibiting signs of mad cow disease; and dead cattle. Pursuant to the USDA Agreement, the USDA agreed to pay Farm Fresh Meats $150 per obex sample for collecting obex samples from cattle within the Targeted Cattle Population, and submitting the obex samples to a USDA laboratory for mad cow disease testing. Farm Fresh Meats further agreed to maintain in cold storage the sampled cattle carcasses and heads until the test results were received by Farm Fresh Meats.
Evidence uncovered during the government’s investigation established that Farm Fresh Meats and Farabee submitted samples from cattle outside the Targeted Cattle Population. Specifically, Farm Fresh Meats and Farabee submitted, or caused to be submitted, obex samples from healthy, USDA inspected cattle, in order to steal government moneys.
Evidence collected also demonstrated that Farm Fresh Meats and Farabee failed to maintain cattle carcasses and heads pending test results and falsified corporate books and records to conceal their malfeasance. Such actions, to the extent an obex sample tested positive (fortunately, none did), could have jeopardized the USDA’s ability to identify the diseased animal and pinpoint its place of origin. On Wednesday, February 14, 2007, Farm Fresh Meats and Farabee pleaded guilty to stealing government funds and using the mails and wires to effect the scheme. According to their guilty pleas:
(a) Farm Fresh Meats collected, and Farabee directed others to collect, obex samples from cattle outside the Targeted Cattle Population, which were not subject to payment by the USDA;
(b) Farm Fresh Meats2 and Farabee caused to be submitted payment requests to the USDA knowing that the requests were based on obex samples that were not subject to payment under the USDA Agreement; (c) Farm Fresh Meats completed and submitted, and Farabee directed others to complete and submit, BSE Surveillance Data Collection Forms to the USDA’s testing laboratory that were false and misleading;
(d) Farm Fresh Meats completed and submitted, and Farabee directed others to complete and submit, BSE Surveillance Submission Forms filed with the USDA that were false and misleading;
(e) Farm Fresh Meats falsified, and Farabee directed others to falsify, internal Farm Fresh Meats documents to conceal the fact that Farm Fresh Meats was seeking and obtaining payment from the USDA for obex samples obtained from cattle outside the Targeted Cattle Population; and
(f) Farm Fresh Meats failed to comply with, and Farabee directed others to fail to comply with, the USDA Agreement by discarding cattle carcasses and heads prior to receiving BSE test results.
A conviction for theft of government funds carries a maximum penalty of 10 years imprisonment. Mail fraud and wire fraud convictions carry a maximum penalty of 20 years imprisonment. Convictions for the above referenced violations also carry a maximum fine of $250,000 for individuals and $500,000 for organizations. In determining an actual sentence, Judge Earl H. Carroll will consult the U.S. Sentencing Guidelines, which provide appropriate sentencing ranges. The judge, however, is not bound by those guidelines in determining a sentence. Sentencing is set before Judge Earl H. Carroll on May 14, 2007. The investigation in this case was conducted by Assistant Special Agent in Charge Alejandro Quintero, United States Department of Agriculture, Office of Inspector General. The prosecution is being handled by Robert Long, Assistant U.S. Attorney, District of Arizona, Phoenix.
CASE NUMBER: CR-07-00160-PHX-EHC RELEASE NUMBER: 2007-051(Farabee) # # #
http://www.usdoj.gov/usao/az/press_releases/2007/2007-051(Farabee).pdf
USA MAD COW POLICY, don't look, don't find, or screw the testing up so bad, everything comes out negative. UNLESS of course you get the end around by the Honorable Phyllis Fong of the OIG. Course, that was a one time deal. But what a coup it was. ...TSS
-------- Original Message --------
Subject: USA BIO-RADs INCONCLUSIVEs
Date: Fri, 17 Dec 2004 15:37:28 -0600
From: "Terry S. Singeltary Sr."
To: susan_berg@bio-rad.com
Hello Susan and Bio-Rad,
Happy Holidays!
I wish to ask a question about Bio-Rad and USDA BSE/TSE testing and there inconclusive. IS the Bio-Rad test for BSE/TSE that complicated, or is there most likely some human error we are seeing here?
HOW can Japan have 2 positive cows with No clinical signs WB+, IHC-, HP- , BUT in the USA, these cows are considered 'negative'?
IS there more politics working here than science in the USA?
What am I missing?
-------- Original Message --------
Subject: Re: USDA: More mad cow testing will demonstrate beef's safety
Date: Fri, 17 Dec 2004 09:26:19 -0600
From: "Terry S. Singeltary Sr." snip...end
Experts doubt USDA's mad cow results
snip...END
WELL, someone did call me from Bio-Rad about this, however it was not Susan Berg. but i had to just about take a blood oath not to reveal there name. IN fact they did not want me to even mention this, but i feel it is much much to important. I have omitted any I.D. of this person, but thought I must document this ;
Bio-Rad, TSS phone conversation 12/28/04
SNIP...
full text ;
http://madcowtesting.blogspot.com/2008/01/bse-oie-usda.html
Saturday, August 16, 2008
Qualitative Analysis of BSE Risk Factors in the United States February 13, 2000 at 3:37 pm PST (BSE red book)
http://bseusa.blogspot.com/2008/08/qualitative-analysis-of-bse-risk.html
48 hour traceback for BSE mad cow disease in the USA ???
NOT in your lifetime !
8 YEARS IN REVIEW OF THE MAD COW DEBACLE IN THE USA ;
http://bse-atypical.blogspot.com/2008/12/mad-cow-disease-usa-december-28-2008-8.html
Thursday, June 24, 2010
Accumulation of L-type Bovine Prions in Peripheral Nerve Tissues
Volume 16, Number 7–July 2010
http://bse-atypical.blogspot.com/2010/06/accumulation-of-l-type-bovine-prions-in.html
Saturday, June 19, 2010
U.S. DENIED UPGRADED BSE STATUS FROM OIE
see full text and reasons why here ;
http://usdameatexport.blogspot.com/2010/06/us-denied-upgraded-bse-status-from-oie.html
Wednesday, March 31, 2010
Atypical BSE in Cattle
http://bse-atypical.blogspot.com/2010/03/atypical-bse-in-cattle-position-post.html
Saturday, June 12, 2010
PUBLICATION REQUEST AND FOIA REQUEST Project Number: 3625-32000-086-05 Study of Atypical Bse
http://bse-atypical.blogspot.com/2010/06/publication-request-and-foia-request.html
Wednesday, February 24, 2010
Transmissible Spongiform encephalopathy (TSE) animal and human TSE in North America 14th
ICID International Scientific Exchange Brochure -
http://transmissiblespongiformencephalopathy.blogspot.com/2010/02/transmissible-spongiform-encephalopathy.html
PEOPLE wonder why there is no mad cows in the USA. I don't. It's as obvious as the day is long $$$
RAMIFICATIONS OF USA POLICY ON MAD COW DISEASE as follows ;
Thursday, July 08, 2010
GLOBAL CLUSTERS OF CREUTZFELDT JAKOB DISEASE - A REVIEW 2010
http://creutzfeldt-jakob-disease.blogspot.com/2010/07/global-clusters-of-creutzfeldt-jakob.html
Thursday, July 08, 2010
Nosocomial transmission of sporadic Creutzfeldt-Jakob disease: results from a risk-based assessment of surgical interventions Public release date: 8-Jul-2010
http://creutzfeldt-jakob-disease.blogspot.com/2010/07/nosocomial-transmission-of-sporadic.html
Tuesday, June 1, 2010
USA cases of dpCJD rising with 24 cases so far in 2010
http://cjdtexas.blogspot.com/2010/06/usa-cases-of-dpcjd-rising-with-24-cases.html
Wednesday, June 16, 2010
Defining sporadic Creutzfeldt-Jakob disease strains and their transmission properties
http://creutzfeldt-jakob-disease.blogspot.com/2010/06/defining-sporadic-creutzfeldt-jakob.html
Archive Number 20100405.1091 Published Date 05-APR-2010
Subject PRO/AH/EDR> Prion disease update 1010 (04)
snip...
[Terry S. Singeltary Sr. has added the following comment:
"According to the World Health Organisation, the future public health threat of vCJD in the UK and Europe and potentially the rest of the world is of concern and currently unquantifiable. However, the possibility of a significant and geographically diverse vCJD epidemic occurring over the next few decades cannot be dismissed.
The key word here is diverse. What does diverse mean? If USA scrapie transmitted to USA bovine does not produce pathology as the UK c-BSE, then why would CJD from there look like UK vCJD?"
http://www.promedmail.org/pls/apex/f?p=2400:1001:568933508083034::NO::F2400_P1001_BACK_PAGE,F2400_P1001_PUB_MAIL_ID:1000,82101
> Up until about 6 years ago, the pt worked at Tyson foods where she
> worked on the assembly line, slaughtering cattle and preparing them for
> packaging. She was exposed to brain and spinal cord matter when she
> would euthanize the cattle.
http://www.recordandoalinda.com/index.php?option=com_content&view=article&id=19:cjd-english-info&catid=9:cjd-ingles&Itemid=8
CJD TEXAS 38 YEAR OLD FEMALE WORKED SLAUGHTERING CATTLE EXPOSED TO BRAIN AND SPINAL CORD MATTER
http://cjdtexas.blogspot.com/2010/03/cjd-texas-38-year-old-female-worked.html
Monday, April 5, 2010
UPDATE - CJD TEXAS 38 YEAR OLD FEMALE WORKED SLAUGHTERING CATTLE EXPOSED TO BRAIN AND SPINAL CORD MATTER
http://prionunitusaupdate2008.blogspot.com/2010/04/update-cjd-texas-38-year-old-female.html
Friday, November 30, 2007
CJD QUESTIONNAIRE USA CWRU AND CJD FOUNDATION
http://cjdquestionnaire.blogspot.com/
TSS
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