ONE HUNDREDTH MEETING OF THE SPONGIFORM ENCEPHALOPATHY ADVISORY COMMITTEE
The Spongiform Encephalopathy Advisory Committee held its 100th meeting in London on 25th April 2008, and discussed the following:
SEAC was informed about:
• Two recently identified cases of variant Creutzfeldt-Jakob Disease (vCJD) in Spain. • Proposals for the future regulation of ‘high street’ dentistry outlined in a consultation issued recently by the Department of Health (DH)1. SEAC agreed to respond to the consultation, welcoming the proposals. • The detection of material of unknown animal origin in a batch of wheat feed distributed for use in livestock feed2.
ASSESSMENT OF THE PREVALENCE OF SUBCLINICAL vCJD SEAC was updated about the progress of the National Anonymous Tonsil Archive (NATA) and of discussions around a proposed post mortem tissue archive. These would provide data to estimate the prevalence of subclinical vCJD (vCJD infections that have yet to develop, or may never develop, into clinical disease). Approximately 55 000 NATA samples had been screened by the end of March 2008. Although none was positive for abnormal prion protein (PrPvCJD), some testing remains to be done on some samples. SEAC expressed disappointment that it is currently
1 DH (2008) The future regulation of health and adult social care in England: A consultation on the framework for the registration of health and adult social care providers.
2 © SEAC 2008
proving difficult to establish a post mortem tissue archive through collection of tissues from Coroners’ autopsies. In light of the current difficulties in establishing a post mortem tissue archive, DH asked for advice about how existing data from NATA might be combined with a completed survey of appendix samples3, which had found PrPvCJD in three out of about 11 000 samples. SEAC considered that the data from these studies are not, at the present time, discrepant. However, given the uncertainties about the tissue distribution of PrPvCJD during vCJD incubation, it would be hard to see how these data could be combined.
SEAC considered what further work might be done to obtain better estimates for the prevalence of subclinical vCJD including additional appendix studies and a post mortem tissue archive. SEAC strongly recommended that every avenue be pursued to establish such an archive.
The committee agreed to produce a statement.
UPDATE ON ANIMAL TSEs
SEAC was updated on transmissible spongiform encephalopathies (TSEs) in animals in the UK and elsewhere.
In the UK, the Bovine Spongiform Encephalopathy (BSE) epidemic in cattle peaked in 1992, with over 37 000 confirmed cases but has since declined with 67 cases confirmed in 2007. By the end of 2007, there had been 178 BSE cases confirmed in the UK in cattle born after the introduction of the reinforced feed ban in 1996. Two unusual (H-type) BSE cases have been found in the UK. Relatively low numbers of BSE cases have also been found in the other European Union (EU) countries and elsewhere.
No TSEs have been found in a relatively small EU survey of deer. There is no evidence for the presence of BSE from surveillance of UK sheep. Classical scrapie case numbers continue to decline in the UK with 31 cases confirmed in 2007. Small numbers of
3 Hilton et al. (2004) Prevalence of lymphoreticular prion protein accumulation in UK tissue samples. J Pathol. 203, 733-739.
3 © SEAC 2008
atypical scrapie cases continue to be found with a total of 194 cases confirmed in the UK since surveillance for atypical scrapie began in 2002. Classical and atypical scrapie continue to be found in EU and other countries.
CONSIDERATION OF OPTIONS FOR RELAXATION OF THE TOTAL FEED BAN
At SEAC 99, Rural Affairs Departments and the Food Standards Agency (FSA) asked SEAC to assess the possible consequences of various options for relaxing the total feed ban. These included the introduction of tolerance levels for certain types of processed animal protein (PAP) in feed, the inclusion of fish meal in young ruminant diets and the feeding of non-ruminant PAP to nonruminants of a different species. Following that meeting, a draft statement was prepared based on the discussions.
SEAC discussed the draft statement and agreed modifications. Once the statement is finalised, it will be published on the SEAC website.
PROPOSALS TO REDUCE TESTING OF CATTLE SLAUGHTERED FOR FOOD – IMPACT ON RISK TO HUMAN HEALTH
FSA asked SEAC to consider an analysis of the human health risk of a range of options for altering the BSE surveillance programme by increasing the minimum age at which healthy slaughtered and fallen stock cattle must be tested for BSE. A BSE risk model constructed by the Veterinary Laboratories Agency, that had been previously reviewed and accepted by SEAC, was used for the analysis.
SEAC noted that the increased risks calculated by the model arising as a result of raising the age at which cattle are tested for BSE are very small. These calculations are subject to uncertainties, particularly in relation to assumptions made about infectivity in tissues and the BSE epidemic. The committee asked for further information about how well outputs from the model fit actual surveillance data. SEAC suggested that future modelling could examine the effect of changing controls on effectiveness of one control. SEAC noted that BSE testing of cattle provides
4 © SEAC 2008
important data on the incidence of the disease and confers some public health protection.
SEAC considered issues that might emerge on the TSE science horizon. It noted that significant progress continues to be made to understand TSEs better and to develop effective TSE control policies. SEAC considered areas of TSE science important for the future could include the:
• nature of the TSE carrier state • genetic factors that modulate susceptibility to TSEs • molecular basis of TSE strains and the relationship with host genetics • potential for animal TSEs to transmit to humans • development of ante mortem diagnostic tests • proportionality of TSE controls
The finalised minutes of the 99th meeting
Thursday, January 31, 2008
SPONGIFORM ENCEPHALOPATHY ADVISORY COMMITTEE Draft minutes of the 99th meeting held on 14th December 2007
ITEM 8 – PUBLIC QUESTION AND ANSWER SESSION
40. The Chair explained that the purpose of the question and answer session was to give members of the public an opportunity to ask questions related to the work of SEAC. Mr Terry Singeltary (Texas, USA) had submitted a question prior to the meeting, asking: “With the Nor-98 now documented in five different states so far in the USA in 2007, and with the two atypical BSE H-base
13 © SEAC 2007
cases in Texas and Alabama, with both scrapie and chronic wasting disease (CWD) running rampant in the USA, is there any concern from SEAC with the rise of sporadic CJD in the USA from ''unknown phenotype'', and what concerns if any, in relations to blood donations, surgery, optical, and dental treatment, do you have with these unknown atypical phenotypes in both humans and animals in the USA? Does it concern SEAC, or is it of no concern to SEAC? Should it concern USA animal and human health officials?”
41. A member considered that this question ............
snip... please see full text, sources, and comments here ;
FC5.3 Assessing the Risk of vCJD Transmission by Dentistry; Distribution of Infectivity in Oral Tissues of VM Mice after Simulated Oral Feeding of BSE-301V
Sutton, JM1; Kirby, E1; Dickinson, J1; Dennis, M1; Cornwall, M1; Vassey, MJ1; Smith, A2; Marsh, PD3; Walker, JT1; Raven, NDH1 1Health Protection Agency, Centre for Emergency Preparedness and Response,, TSE Research group, UK; 2University of Glasgow, Dental School, UK; 3Health Protection Agency, Centre for Emergency Preparedness and Response,, UK
Background: Ongoing concerns about the prevalence of variant Creutzfeldt Jakob Disease (vCJD) in the UK population has heightened concerns about the risks of iatrogenic transmission of the disease. Although there have been no cases to date of transmission by surgery there have been 4 cases involving blood transfusion. This study aims to assess the potential of transmission of the disease by dental procedures. Whilst the risks are undoubtably low the very large numbers of procedures carried out annually have the potential to amplify the risks considerably and there is very little data in this area to form the basis for accurate risk assessments. Aim(s)/Objective(s): To assess the relative levels of infectivity in oral tissues from a murine model following exposure to BSE-301V through the small intestine. Methods. The study uses a BSE-301V, VM mouse model as a clinically relevant model for assessing iatrogenic vCJD transmission between humans. Infectious mouse brain homogenate was prepared and inoculated into a loop of the duodenum, to prevent direct contamination of the oral tissues. Mice were sacrificed at 3-weekly intervals and at appearance of clinical symptoms. A range of oral tissues, including dental pulp, gingival margin, salivary gland, saliva, lingual tonsil and trigeminal ganglia, together with brain and spleen tissues were removed, processed as homogenates and reinoculated intracranially (ic.) into indicator mice. Results: The primary challenge proved to be a very efficient route of infection with a 100% attack rate and a mean incubation to clinical disease of 157 ± 17 days (compared to 120 days for the same titre inoculum ic.). Infectivity was observed in all oral and control tissues with varying time-courses and titres estimated from incubation period. Discussion: The results throw new light on the potential routes of dissemination and spread of infectivity from the small intestine to the oral cavity and its implications for possible iatrogenic transmission of vCJD via dental, endoscopic or other forms of surgery. Conclusion: The data generated from the study provides support for ongoing risk assessments to look at the potential for vCJD transmission via dental procedures alongside other elements of studies looking at effectiveness of decontamination and re-use of dental instruments.
Monday, December 31, 2007
Risk Assessment of Transmission of Sporadic Creutzfeldt-Jakob Disease in Endodontic Practice in Absence of Adequate Prion Inactivation
Subject: CJD: update for dental staff Date: November 12, 2006 at 3:25 pm PST
1: Dent Update. 2006 Oct;33(8):454-6, 458-60.
CJD: update for dental staff.
Scully C, Smith AJ, Bagg J. Eastman Dental Institute, University of London.
It is almost a decade since the recognition of the emergence of a new infectious disease termed variant Creutzfeldt-Jakob disease (vCJD) caused by prions (PrPTSE), abnormal variants of a normal human cell surface protein (PrP).This disease has a number of similarities to other forms of CJD--lethal disorders characterized by a prolonged incubation period, and progressive mental deterioration. In relation to oral tissues, PrPTSE have been found in neural, gingival, pulpal, lingual, lymphoreticular and salivary gland tissue in animal models. In both sporadic and variant CJD, PrPTSE is detectable in the trigeminal ganglion and, in vCJD, in lymphoreticular tissues, but infectivity has not been tested in other human oral tissues. CLINICAL RELEVANCE: PrPTSE is much more resistant to the common methods of inactivation than conventional pathogens, and it adheres avidly to steel whilst retaining its infectivity. Particular attention must be paid to cleaning and sterilizing re-usable dental instruments. Single-use devices, such as endodontic files and matrix bands, must never be re-used. Advice on the reprocessing of dental instruments used on known CJD patients must be obtained from local infection control teams. Research into effective methods of prion inactivation appears promising, although further work on the applicability to general dental practice is required.
PMID: 17087448 [PubMed - in process]
Subject: PrPSc in salivary glands of scrapie-affected sheep Date: February 15, 2007 at 9:33 am PST
J. Virol. doi:10.1128/JVI.02148-06 Copyright (c) 2007, American Society for Microbiology and/or the Listed Authors/Institutions. All Rights Reserved.
PrPSc in salivary glands of scrapie-affected sheep
Marta Vascellari*, Romolo Nonno, Franco Mutinelli, Michela Bigolaro, Michele Angelo Di Bari, Erica Melchiotti, Stefano Marcon, Claudia D'Agostino, Gabriele Vaccari, Michela Conte, Luigi De Grossi, Francesca Rosone, Francesco Giordani, and Umberto Agrimi Istituto Zooprofilattico Sperimentale delle Venezie, Histopathology Department, Viale dell'Università 10, 35020 Legnaro (PD), Italy; Istituto Superiore di Sanità, Department of Food Safety and Animal Health, Viale Regina Elena 299, 00161 Roma, Italy; Istituto Zooprofilattico Sperimentale delle Regioni Lazio e Toscana, Strada Terme, 01100 Viterbo, Italy
* To whom correspondence should be addressed. Email: firstname.lastname@example.org .
The salivary glands of scrapie-affected sheep and healthy controls were investigated for the presence of the pathological prion protein (PrPSc). PrPSc was detected in major (parotid and mandibular) and minor (buccal, labial and palatine) salivary glands of naturally and experimentally infected sheep. By western blot, PrPSc concentration in glands was estimated as 0.02-0.005% of brain. Immunohistochemistry revealed intracellular deposition of PrPSc in ductal and acinar epithelium and occasional labeling into the lumen of salivary ducts. The presence of PrPSc in salivary glands highlights the possible role of saliva in the horizontal transmission of scrapie.
This study further confirms that BASE is caused by a distinct prion isolate and discloses a novel disease phenotype in cattle, closely resembling the phenotype previous reported in scrapie-inoculated cattle
*** and in some subtypes of inherited and sporadic Creutzfeldt-Jakob disease.
The Italian cases (11 and 15 years of age) originally named bovine amyloidotic spongiform encephalopathy (BASE) were characterized by an unglycosylated protein band with a lower molecular mass (thus named L cases) and the predominance of the monoglycosylated band. In addition, immunohistochemical detection of PrPres in these cases found greater deposits in the cerebral cortex and thalamus versus the brain stem. The French cases found a higher molecular mass associated with the unglycosylated protein band and were called H cases (see figure 1). *** The different "strains" are now called atypical BSE. ...
full text, skroll down to page 6 ;
MAD COW DISEASE terminology UK c-BSE (typical), atypical BSE H or L, and or Italian L-BASE (the last two cases of mad cow disease in the USA were in Alabama, and Texas, both of which were atypical BSE).
Please remember, the last two mad cows documented in the USA i.e. Alabama and Texas, both were of the 'atypical' BSE strain, and immediately after that, the USDA shut down the testing from 470,000 to 40,000 in the U.S. in 2007 out of about 35 million cattle slaughtered. also, science is showing that some of these atypical cases are more virulent to humans than the typical UK BSE strain ;
***Atypical forms of BSE have emerged which, although rare, appear to be more virulent than the classical BSE that causes vCJD.***
Progress Report from the National Prion Disease Pathology Surveillance Center
An Update from Stephen M. Sergay, MB, BCh & Pierluigi Gambetti, MD
April 3, 2008
WHY were they planning to destroy all CJD tissue samples donated ???
Washington Times - Washington,DC,USA NIH may destroy human brain collection
By Steve Mitchell Medical Correspondent
Washington, DC, Mar. 24 (UPI) -- The National Institutes of Health may discard part or all of a rare collection that includes hundreds of human brain samples from patients that suffered from a disorder similar to mad cow disease -- unless another researcher or institution takes them on, United Press International has learned.
Several scientists said the collection, which is held by the NIH's National Institute for Neurological Disorders and Stroke in Bethesda, Md. -- and includes brains and other tissue samples from people afflicted with the brain-wasting illness Creutzfeldt Jakob disease -- is irreplaceable and could even provide insight into treatments for the fatal disorder.
Currently, there is no cure for CJD and patients typically die within a year after symptoms begin.
However, NIH officials in control of the collection's fate told UPI the remaining samples are of little scientific value and may be disposed of if researchers outside the agency do not claim it. That position stands in sharp contrast with CJD experts who thought the collection should be preserved.
"It's invaluable," said Dr. Paul Brown, former medical director of the NIH's Laboratory for Central Nervous System Studies, whose expertise is in CJD and mad cow disease (also known as bovine spongiform encephalopathy, or BSE). ...snip...end...tss
NIH says it will preserve CJD brains By STEVE MITCHELL
WASHINGTON, May 31 (UPI) -- The National Institutes of Health apparently has reversed its position on the fate of an invaluable collection of brains from people afflicted with a condition similar to mad cow disease, saying in a letter to a U.S. senator it will not destroy the collection.
May 10, 2005
The Honorable John Cornyn United States Senator Occidental Tower5005 LBJ Freeway, Suite 1150 Dallas, Texas 75244-6199
Dear Senator Cornyn:
Your letter to the National Institutes of Health (NIH) forwarding correspondence from Mr. Terry S. Singeltary, Sr., has been forwarded to me for reply. Mr. Singeltary is concerned about the preservation of Creutzfeldt-Jakob disease (CJD) brain samples that have been maintained by the National Institute of Neurological Disorders and Stroke (NINDS) Intramural Research program for many years.
I am sorry to learn that Mr. Singeltary's mother died of CJD and can certainly understand his desire that any tissues that could help investigators unravel the puzzle of this deadly disease are preserved. I hope he will be pleased to learn that all the brains and other tissues with potential to help scientists learn about CJD are, and will continue to be, conserved. (The tissues that are discarded are those that have either decayed to an extent that renders them no longer appropriatefor research or those for which we do not have sufficient identification.) ...snip...end...tss
NIH says it will preserve CJD brains
Published: May 31, 2005 at 5:26 PM
By STEVE MITCHELL WASHINGTON, May 31 (UPI) -- The National Institutes of Health apparently has reversed its position on the fate of an invaluable collection of brains from people afflicted with a condition similar to mad cow disease, saying in a letter to a U.S. senator it will not destroy the collection.
An NIH official had told United Press International previously that the brain collection, which consists of samples from hundreds of people who died from the brain-wasting illness called Creutzfeldt Jakob disease, could be discarded if another entity does not claim them.
That sparked an outcry from patient-advocacy groups, consumer watchdogs and scientists, and the agency now appears to have backed away from that course.
"All the brains and other tissues with potential to help scientists learn about CJD are, and will continue to be, conserved," Story Landis, director of the National Institute of Neurological Disorders and Stroke, which oversees the brain collection, wrote in a May 10 letter to Sen. John Cornyn, R-Texas.
Cornyn had inquired about the status of the collection in April.
Last March, Eugene Major, acting director of the basic neuroscience program at the NIH, told UPI the useful portions of the collection had been doled out to scientists and the remaining samples had "very little remaining value" and could be destroyed.
Landis could not be reached for comment Tuesday. NINDS spokesman Paul Girolami told UPI he had been unable to locate her.
Scientists think the collection, which dates back to 1963, is invaluable for research on CJD and similar diseases and could even provide insight into treatments. There is no cure for CJD and patients typically die within a year after symptoms begin.
"Absolutely, the collection is worth keeping," Bruce Johnson, a former NIH scientist who said he had been told the collection would be destroyed in two years if no one took the samples from the agency, told UPI.
The Memorial Institute for Neurodegenerative Diseases Inc., a non-profit organization consisting of more than 40 researchers from several countries, offered to take the collection off of NIH's hands more than a year ago and so far has not heard anything from the agency, Harry Peery, MIND's executive director, told UPI.
CJD belongs to a group of incurable and fatal diseases collectively known as transmissible spongiform encephalopathies, or TSEs, that includes mad cow disease in cows, chronic wasting disease in deer and elk, and scrapie in sheep.
Variant CJD, or vCJD, is a relatively new TSE, which people can contract from consuming beef products infected with the mad cow pathogen.
Despite Landis' assurance the collection will be preserved, some family members of the patients who donated their brains to the NIH are still skeptical. This is because the wording Landis used in the letter leaves open the possibility that some brain samples are being destroyed.
"The tissues that are discarded are those that have either decayed to an extent that renders them no longer appropriate for research or those for which we do not have sufficient identification," Landis wrote.
"Which ones" are being destroyed? asked Terry Singeltary, who is involved with several CJD patient groups.
"With a system like this, they could destroy whatever and whenever they wanted, for whatever reason they wanted," Singeltary, whose mother died of CJD in 1997, told UPI.
"It's a perfect excuse to discard some suspicious tissue resembling vCJD or some atypical TSE related to animal TSEs in the USA," he added.
Although the collection includes samples from CJD patients as young as 16 that could make them candidates for possible vCJD, the brains have never been screened for evidence of the disease. The only confirmed vCJD case in the United States occurred in a Florida woman who is thought to have contracted the disease in England.
Johnson said he along with renowned CJD expert Paul Brown were in the process of sorting through the samples to match them up with patient identification documents until they both retired. Some of the samples may prove impossible to identify, he said, but he and Brown are the only ones familiar enough with the collection to organize it and neither has been asked back by the agency to aid in the identification process.
Steve Mitchell is UPI's Medical Correspondent. E-mail: email@example.com
© 2005 United Press International. All Rights Reserved. This material may not be reproduced, redistributed, or manipulated in any form.
In this context, a word is in order about the US testing program. After the discovery of the first (imported) cow in 2003, the magnitude of testing was much increased, reaching a level of >400,000 tests in 2005 (Figure 4). Neither of the 2 more recently indigenously infected older animals with nonspecific clinical features would have been detected without such testing, and neither would have been identified as atypical without confirmatory Western blots. Despite these facts, surveillance has now been decimated to 40,000 annual tests (USDA news release no. 0255.06, July 20, 2006) and invites the accusation that the United States will never know the true status of its involvement with BSE.
In short, a great deal of further work will need to be done before the phenotypic features and prevalence of atypical BSE are understood. More than a single strain may have been present from the beginning of the epidemic, but this possibility has been overlooked by virtue of the absence of widespread Western blot confirmatory testing of positive screening test results; or these new phenotypes may be found, at least in part, to result from infections at an older age by a typical BSE agent, rather than neonatal infections with new "strains" of BSE. Neither alternative has yet been investigated.
CDC DR. PAUL BROWN TSE EXPERT COMMENTS 2006
The U.S. Department of Agriculture was quick to assure the public earlier this week that the third case of mad cow disease did not pose a risk to them, but what federal officials have not acknowledged is that this latest case indicates the deadly disease has been circulating in U.S. herds for at least a decade.
The second case, which was detected last year in a Texas cow and which USDA officials were reluctant to verify, was approximately 12 years old.
These two cases (the latest was detected in an Alabama cow) present a picture of the disease having been here for 10 years or so, since it is thought that cows usually contract the disease from contaminated feed they consume as calves. The concern is that humans can contract a fatal, incurable, brain-wasting illness from consuming beef products contaminated with the mad cow pathogen.
"The fact the Texas cow showed up fairly clearly implied the existence of other undetected cases," Dr. Paul Brown, former medical director of the National Institutes of Health's Laboratory for Central Nervous System Studies and an expert on mad cow-like diseases, told United Press International. "The question was, 'How many?' and we still can't answer that."
Brown, who is preparing a scientific paper based on the latest two mad cow cases to estimate the maximum number of infected cows that occurred in the United States, said he has "absolutely no confidence in USDA tests before one year ago" because of the agency's reluctance to retest the Texas cow that initially tested positive.
USDA officials finally retested the cow and confirmed it was infected seven months later, but only at the insistence of the agency's inspector general.
"Everything they did on the Texas cow makes everything USDA did before 2005 suspect," Brown said. ...snip...end
CDC - Bovine Spongiform Encephalopathy and Variant Creutzfeldt ... Dr. Paul Brown is Senior Research Scientist in the Laboratory of Central Nervous System ... Address for correspondence: Paul Brown, Building 36, Room 4A-05, ...
PAUL BROWN COMMENT TO ME ON THIS ISSUE
Tuesday, September 12, 2006 11:10 AM
"Actually, Terry, I have been critical of the USDA handling of the mad cow issue for some years, and with Linda Detwiler and others sent lengthy detailed critiques and recommendations to both the USDA and the Canadian Food Agency."
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.
NOT to forget the 5 cases of the NOR-98 atypical scrapie documented in the USA in 2007, in five different states. WHICH pathologically looks like some sub-types of sporadic CJD, of which Stanely Prusiner warns of a public health risk ;
***The pathology features of Nor98 in the cerebellum of the affected sheep showed similarities with those of sporadic Creutzfeldt-Jakob disease in humans.
Here we report that both Nor98 and discordant cases, including three sheep homozygous for the resistant PrPARR allele (A136R154R171), efficiently transmitted the disease to transgenic mice expressing ovine PrP, and that they shared unique biological and biochemical features upon propagation in mice. These observations support the view that a truly infectious TSE agent, unrecognized until recently, infects sheep and goat flocks and may have important implications in terms of scrapie control and public health.
Edited by Stanley B. Prusiner, University of California, San Francisco, CA, and approved September 12, 2005 (received for review March 21, 2005)
Tuesday, June 3, 2008
SCRAPIE USA UPDATE JUNE 2008 NOR-98 REPORTED PA
Thursday, April 03, 2008 A prion disease of cervids: Chronic wasting disease 2008
1: Vet Res. 2008 Apr 3;39(4):41
Transmissible Mink Encephalopathy TME
Communicated by: Terry S. Singeltary Sr.
[In submitting these data, Terry S. Singeltary Sr. draws attention to the steady increase in the "type unknown" category, which, according to their definition, comprises cases in which vCJD could be excluded. The total of 26 cases for the current year (2007) is disturbing, possibly symptomatic of the circulation of novel agents. Characterization of these agents should be given a high priority. - Mod.CP]
There is a growing number of human CJD cases, and they were presented last week in San Francisco by Luigi Gambatti(?) from his CJD surveillance collection.
He estimates that it may be up to 14 or 15 persons which display selectively SPRPSC and practically no detected RPRPSC proteins.
The statistical incidence of CJD cases in the United States has been revised to reflect that there is one case per 9000 in adults age 55 and older. Eighty-five percent of the cases are sporadic, meaning there is no known cause at present.
Journal of American Medical Association
Diagnosis and Reporting of Creutzfeldt-Jakob Disease Singeltary, Sr et al. JAMA.2001; 285: 733-734. Vol. 285 No. 6, February 14, 2001 JAMA
Diagnosis and Reporting of Creutzfeldt-Jakob Disease
To the Editor: In their Research Letter, Dr Gibbons and colleagues1 reported that the annual US death rate due to Creutzfeldt-Jakob disease (CJD) has been stable since 1985. These estimates, however, are based only on reported cases, and do not include misdiagnosed or preclinical cases. It seems to me that misdiagnosis alone would drastically change these figures. An unknown number of persons with a diagnosis of Alzheimer disease in fact may have CJD, although only a small number of these patients receive the postmortem examination necessary to make this diagnosis. Furthermore, only a few states have made CJD reportable. Human and animal transmissible spongiform encephalopathies should be reportable nationwide and internationally.
Terry S. Singeltary, Sr Bacliff, Tex
1. Gibbons RV, Holman RC, Belay ED, Schonberger LB. Creutzfeldt-Jakob disease in the United States: 1979-1998. JAMA. 2000;284:2322-2323. FREE FULL TEXT
2 January 2000 British Medical Journal
U.S. Scientist should be concerned with a CJD epidemic in the U.S., as well
15 November 1999 British Medical Journal vCJD in the USA * BSE in U.S.
JOURNAL OF NEUROLOGY
MARCH 26, 2003
RE-Monitoring the occurrence of emerging forms of Creutzfeldt-Jakob
disease in the United States
Email Terry S. Singeltary:
I lost my mother to hvCJD (Heidenhain Variant CJD). I would like to comment on the CDC's attempts to monitor the occurrence of emerging forms of CJD. Asante, Collinge et al  have reported that BSE transmission to the 129-methionine genotype can lead to an alternate phenotype that is indistinguishable from type 2 PrPSc, the commonest sporadic CJD. However, CJD and all human TSEs are not reportable nationally. CJD and all human TSEs must be made reportable in every state and internationally. I hope that the CDC does not continue to expect us to still believe that the 85%+ of all CJD cases which are sporadic are all spontaneous, without route/source. We have many TSEs in the USA in both animal and man. CWD in deer/elk is spreading rapidly and CWD does transmit to mink, ferret, cattle, and squirrel monkey b y intracerebral inoculation. With the known incubation periods in other TSEs, oral transmission studies of CWD may take much longer. Every victim/family of CJD/TSEs should be asked about route and source of this agent. To prolong this will only spread the agent and needlessly expose others. In light of the findings of Asante and Collinge et al, there should be drastic measures to safeguard the medical and surgical arena from sporadic CJDs and all human TSEs. I only ponder how many sporadic CJDs in the USA are type 2 PrPSc?
Newsletter issue 17 april 2008
the importance of gene types
We have known for many years that a common variation in a gene, known as the prion protein gene, is very important in determining the risk of developing prion diseases and how long it takes for the disease to develop when someone becomes infected. There are three genetic types in the UK population known as MM, VV and MV. So far, vCJD has only affected people with MM genetic type. Around 40% of healthy people in the UK are MM, about 50% are MV and around 10% are VV. It is likely that BSE prions will infect people of the VV and MV types also, but they may have much longer incubation periods (the time taken from being infected with prions until the brain disease becomes apparent) and may also develop a pattern of disease which may be different to vCJD. We suspect this again as result of research in laboratory mice wher e those that had the VV and MV genes had a different type of disease and different types or ‘strains’ of prions developed.
This unusual finding reminds us of the importance of keeping alert to the possibility that BSE prions will cause disease in individuals with different genetic types, who may develop a disease that may resemble sporadic CJD, or vCJD, or have a new pattern of disease.
Prion disease and gene types
Dr Simon Mead and Professor John Collinge, NHS National Prion Clinic
Reference: Creutzfeldt-Jakob Disease, Prion Protein Gene Codon 129VV, and a Novel PrPSc Type in a Young British Woman Simon Mead; Susan Joiner; Melanie Desbruslais; Jonathan A. Beck; Michael O’ Donoghue; Peter Lantos; Jonathan D. F. Wadsworth; John Collinge Arch Neurol. 2007;64(12):1780-1784.
THE PATHOLOGICAL PROTEIN
Hardcover, 304 pages plus photos and illustrations. ISBN 0-387-95508-9
BY Philip Yam
CHAPTER 14 LAYING ODDS
Answering critics like Terry Singeltary, who feels that the U.S. under- counts CJD, Schonberger conceded that the current surveillance system has errors but stated that most of the errors will be confined to the older population.
The statistical incidence of CJD cases in the United States has been revised to reflect that there is one case per 9000 in adults age 55 and older. Eighty-five percent of the cases are sporadic, meaning there is no known cause at present.
Terry S. Singeltary Sr. P.O. Box 42 Bacliff, Texas USA 77518