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.
http://www.cdc.gov/ncidod/EID/vol12no12/06-0965.htm
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
http://www.upi.com/ConsumerHealthDaily/view.php?StoryID=20060315-055557-1284r
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, ...
http://www.cdc.gov/ncidod/eid/vol7no1/brown.htm
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."
http://lists.ifas.ufl.edu/cgi-bin/wa.exe?A2=ind0703&L=sanet-mg&T=0&P=8125
Volume 12, Number 12–December 2006
PERSPECTIVE
On the Question of Sporadic
or Atypical Bovine SpongiformEncephalopathy and
Creutzfeldt-Jakob Disease
Paul Brown,* Lisa M. McShane,† Gianluigi Zanusso,‡ and Linda Detwiler§
A link between BSE and
sporadic CJD has been suggested on the basis of laboratory
studies but is unsupported by epidemiologic observation.
Such a link might yet be established by the discovery
of a specific molecular marker or of particular combinations
of trends over time of typical and atypical BSE and various
subtypes of sporadic CJD, as their numbers are influenced
by a continuation of current public health measures that
exclude high-risk bovine tissues from the animal and
human food chains.
SNIP...
Sporadic CJD
The possibility that at least some cases of apparently sporadic CJD might be due to infection by sporadic cases of BSE cannot be dismissed outright. Screening programs needed to identify sporadic BSE have yet to be implemented, and we know from already extant testing programs that at least a proportion of infected animals have no symptoms and thus would never be identified in the absence of systematic testing. Thus, sporadic BSE (or for that matter, sporadic disease in any mammalian species) might be occurring on a regular basis at perhaps the same annual frequency as sporadic CJD in humans, that is, in the range of 1 case per million animals.
Whether humans might be more susceptible to atypical forms of BSE cannot be answered at this time. Experimentally transmitted BASE shows shorter incubation periods than BSE in at least 1 breed of cattle, bovinized transgenic mice, and Cynomolgus monkeys (12,13). In humanized transgenic mice, BASE transmitted, whereas typical BSE did not transmit (13). Paradoxically, the other major phenotype (H) showed an unusually long incubation period in bovinized transgenic mice (12).
The limited experimental evidence bearing on a possible relationship between BSE and sporadic CJD is difficult to interpret. The original atypical BASE strain of BSE had a molecular protein signature very similar to that of 1 subtype (type 2 M/V) of sporadic CJD in humans (5). In another study, a strain of typical BSE injected into humanized mice encoding valine at codon 129 showed a glycopattern indistinguishable from the same subtype of sporadic CJD (15). In a third study, the glycopatterns of both the H and L strains of atypical BSE evidently did not resemble any of the known sporadic CJD subtypes (12).
To these molecular biology observations can be added the epidemiologic data accumulated during the past 30 years. The hypothesis that at least some cases of apparently sporadic CJD are due to unrecognized BSE infections cannot be formally refuted, but if correct, we might expect by now to have some epidemiologic evidence linking BSE to at least 1 cluster of apparently sporadic cases of CJD. Although only a few clusters have been found (and still fewer published), every proposed cluster that has been investigated has failed to show any common exposure to bovines. For that matter, no common exposure has been shown to any environmental vehicles of infection, including the consumption of foodstuffs from bovine, ovine, and porcine sources, the 3 livestock species known to be susceptible to transmissible spongiform encephalopathies. Additional negative evidence comes from several large case-control studies in which no statistically significant dietary differences were observed between patients with sporadic CJD and controls (16,17).
On the other hand, the difficulty of establishing a link between BSE and CJD may be compounded by our ignorance of the infectious parameters of a sporadic form of BSE (e.g., host range, tissue distribution of infectivity, route of transmission, minimum infectious dose for humans, whether single or multiple). Presumably, these parameters would resemble those of variant CJD; that is, high infectivity central nervous system and lymphoreticular tissues of an infected cow find their way into products consumed by humans. Transmissions that might have occurred in the past would be difficult to detect because meat products are generally not distributed in a way that results in detectable geographic clusters.
Barring the discovery of a specific molecular signature (as in variant CJD), the most convincing clue to an association will come from the observation of trends over time of the incidence of typical and atypical BSE and of sporadic and variant CJD. With 4 diseases, each of which could have increasing, unchanging, or decreasing trends, there could be 81 (34) possible different combinations. However, it is highly likely that the trends for typical BSE and variant CJD will both decrease in parallel as feed bans continue to interrupt recycled contamination. The remaining combinations are thus reduced to 9 (32), and some of them could be highly informative.
For example, if the incidence of atypical BSE declines in parallel with that of typical BSE, its candidacy as a sporadic form of disease would be eliminated (because sporadic disease would not be influenced by current measures to prevent oral infection). If, on the other hand, atypical BSE continues to occur as typical BSE disappears, this would be a strong indication that it is indeed sporadic, and if in addition at least 1 form of what is presently considered as sporadic CJD (such as the type 2 M/V subtype shown to have a Western blot signature like BASE) were to increase, this would suggest (although not prove) a causal relationship (Figure 5).
Recognition of the different forms of BSE and CJD depends upon continuing systematic testing for both bovines and humans, but bovine testing will be vulnerable to heavy pressure from industry to dismantle the program as the commercial impact of declining BSE cases ceases to be an issue. Industry should be aware, however, of the implications of sporadic BSE. Its occurrence would necessitate the indefinite retention of all of the public health measures that exclude high-risk bovine tissues from the animal and human food chains, whereas its nonoccurrence would permit tissues that are now destroyed to be used as before, once orally acquired BSE has disappeared.
SNIP...
PLEASE READ FULL TEXT ;
http://www.cdc.gov/ncidod/EID/vol12no12/06-0965.htm?s_cid=eid06_0965_e
THE SEVEN SCIENTIST REPORT ***
http://www.fda.gov/ohrms/dockets/dockets/02n0273/02n-0273-EC244-Attach-1.pdf
full text ;
http://bse-atypical.blogspot.com/2006/08/bse-atypical-texas-and-alabama-update.html
Thursday, January 31, 2008
Evaluation of the Human Transmission Risk of an Atypical Bovine Spongiform
Encephalopathy Prion Strain
J. Virol. doi:10.1128/JVI.02561-07
Copyright (c) 2008, American Society for Microbiology and/or the Listed
Authors/Institutions.
All Rights Reserved.
Thursday, January 31, 2008
Evaluation of the Human Transmission Risk of an Atypical Bovine Spongiform
Encephalopathy Prion Strain
J. Virol. doi:10.1128/JVI.02561-07
Copyright (c) 2008, American Society for Microbiology and/or the Listed
Authors/Institutions. All Rights Reserved.
Evaluation of the Human Transmission Risk of an Atypical Bovine Spongiform
Encephalopathy Prion Strain
Qingzhong Kong*, Mengjie Zheng, Cristina Casalone, Liuting Qing, Shenghai
Huang, Bikram Chakraborty, Ping Wang, Fusong Chen, Ignazio Cali, Cristiano
Corona, Francesca Martucci, Barbara Iulini, Pierluigi Acutis, Lan Wang,
Jingjing Liang, Meiling Wang, Xinyi Li, Salvatore Monaco, Gianluigi Zanusso,
Wen-Quan Zou, Maria Caramelli, and Pierluigi Gambetti*
Department of Pathology, Case Western Reserve University, Cleveland, OH
44106, USA; CEA, Istituto Zooprofilattico Sperimentale, 10154 Torino, Italy;
Department of Neurological and Visual Sciences, University of Verona, 37134
Verona, Italy
* To whom correspondence should be addressed. Email:
[email protected].
[email protected].
Abstract
Bovine spongiform encephalopathy (BSE), the prion disease in cattle, was
widely believed to have only one strain (BSE-C). BSE-C causes the fatal
prion disease named new variant Creutzfeldt-Jacob disease in humans. Two
atypical BSE strains, BASE (or BSE-L) and BSE-H, have been discovered in
several countries since 2004; their transmissibility and phenotypes in
humans are unknown. We investigated the infectivity and human phenotype of
BASE by inoculating transgenic (Tg) mice expressing the human prion protein
with brain homogenates from two BASE-affected cattle. Sixty percent of the
inoculated Tg mice became infected after 20-22 months incubation, a
transmission rate higher than those reported for BSE-C. A quarter of
BASE-infected Tg mice, but none of the Tg mice infected with a sporadic
human prion disease, showed presence of pathogenic prion protein isoforms in
the spleen, indicating that the BASE prion is intrinsically lymphotropic.
The pathological prion protein isoforms in BASE-infected humanized Tg mouse
brains are different from those of the original cattle BASE or sporadic
human prion disease. Minimal brain spongiosis and long incubation time are
observed in the BASE-infected Tg mice. These results suggest that, in
humans, BASE is a more virulent BSE strain and likely lymphotropic.
http://jvi.asm.org/cgi/content/abstract/JVI.02561-07v1?papetoc
for those interested, further into this study, it gets very interesting ;
http://cjdmadcowbaseoct2007.blogspot.com/2008/02/evaluation-of-human-transmission-risk.html
PLEASE SEE !
P02.35 Molecular Features of the Protease-resistant Prion Protein (PrPres) in H- type BSE
Biacabe, A-G1; Jacobs, JG2; Gavier-Widén, D3; Vulin, J1; Langeveld, JPM2; Baron, TGM1 1AFSSA, France; 2CIDC-Lelystad, Netherlands; 3SVA, Sweden
Western blot analyses of PrPres accumulating in the brain of BSE- infected cattle have demonstrated 3 different molecular phenotypes regarding to the apparent molecular masses and glycoform ratios of PrPres bands. We initially described isolates (H-type BSE) essentially characterized by higher PrPres molecular mass and decreased levels of the diglycosylated PrPres band, in contrast to the classical type of BSE. This type is also distinct from another BSE phenotype named L-type BSE, or also BASE (for Bovine Amyloid Spongiform Encephalopathy), mainly characterized by a low representation of the diglycosylated PrPres band as well as a lower PrPres molecular mass. Retrospective molecular studies in France of all available BSE cases older than 8 years old and of part of the other cases identified since the beginning of the exhaustive surveillance of the disease in 20001 allowed to identify 7 H- type BSE cases, among 594 BSE cases that could be classified as classical, L- or H-type BSE. By Western blot analysis of H-type PrPres, we described a remarkable specific feature with antibodies raised against the C-terminal region of PrP that demonstrated the existence of a more C-terminal cleaved form of PrPres (named PrPres#2 ), in addition to the usual PrPres form (PrPres #1). In the unglycosylated form, PrPres #2 migrates at about 14 kDa, compared to 20 kDa for PrPres #1. The proportion of the PrPres#2 in cattle seems to by higher compared to the PrPres#1. Furthermore another PK–resistant fragment at about 7 kDa was detected by some more N-terminal antibodies and presumed to be the result of cleavages of both N- and C- terminal parts of PrP. These singular features were maintained after transmission of the disease to C57Bl/6 mice. The identification of these two additional PrPres fragments (PrPres #2 and 7kDa band)
*** reminds features reported respectively in sporadic Creutzfeldt-Jakob disease and in Gerstmann-Sträussler-Scheinker (GSS) syndrome in humans.
FC5.5.1 BASE Transmitted to Primates and MV2 sCJD Subtype Share PrP27-30 and PrPSc C-terminal Truncated Fragments
Zanusso, G1; Commoy, E2; Fasoli, E3; Fiorini, M3; Lescoutra, N4; Ruchoux, MM4; Casalone, C5; Caramelli, M5; Ferrari, S3; Lasmezas, C6; Deslys, J-P4; Monaco, S3 1University of Verona, of Neurological and Visual Sciences, Italy; 2CEA, IMETI/SEPIA, France; 3University of Verona, Neurological and Visual Sciences, Italy; 4IMETI/SEPIA, France; 5IZSPLVA, Italy; 6The Scripps Research Insitute, USA
The etiology of sporadic Creutzfeldt-Jakob disease (sCJD), the most frequent human prion disease, remains still unknown. The marked disease phenotype heterogeneity observed in sCJD is thought to be influenced by the type of proteinase K- resistant prion protein, or PrPSc (type 1 or type 2 according to the electrophoretic mobility of the unglycosylated backbone), and by the host polymorphic Methionine/Valine (M/V) codon 129 of the PRNP. By using a two-dimensional gel electrophoresis (2D-PAGE) and imunoblotting we previously showed that in sCJD, in addition to the PrPSc type, distinct PrPSc C-terminal truncated fragments (CTFs) correlated with different sCJD subtypes. Based on the combination of CTFs and PrPSc type, we distinguished three PrPSc patterns: (i) the first was observed in sCJD with PrPSc type 1 of all genotypes,;
(ii) the second was found in M/M-2 (cortical form); (iii) the third in amyloidogenic M/V- 2 and V/V-2 subtypes (Zanusso et al., JBC 2004) . Recently, we showed that sCJD subtype M/V-2 shared molecular and pathological features with an atypical form of BSE, named BASE, thus suggesting a potential link between the two conditions. This connection was further confirmed after 2D-PAGE analysis, which showed an identical PrPSc signature, including the biochemical pattern of CTFs. To pursue this issue, we obtained brain homogenates from Cynomolgus macaques intracerebrally inoculated with brain homogenates from BASE. Samples were separated by using a twodimensional electrophoresis (2D-PAGE) followed by immunoblotting. We here show that the PrPSc pattern obtained in infected primates is identical to BASE and sCJD MV-2 subtype.
*** These data strongly support the link, or at least a common ancestry, between a sCJD subtype and BASE.
This work was supported by Neuroprion (FOOD-CT-2004-506579)
************************************************** *****
USA MAD COW CASES IN ALABAMA AND TEXAS
***PLEASE NOTE***
USA BASE CASE, (ATYPICAL BSE), AND OR TSE (whatever they are calling it today), please note that both the ALABAMA COW, AND THE TEXAS COW,both were ''H-TYPE'', personal communication Detwiler et al Wednesday, August 22, 2007 11:52 PM. ...TSS
http://lists.ifas.ufl.edu/cgi-bin/wa.exe?A2=ind0708&L=sanet-mg&T=0&P=19779
************************************************** *****
FC5.5.2 Transmission of Italian BSE and BASE Isolates in Cattle Results into a Typical BSE Phenotype and a Muscle Wasting Disease
Zanusso, G1; Lombardi, G2; Casalone, C3; D'Angelo, A4; Gelmetti, D2; Torcoli, G2; Barbieri, I2; Corona, C3; Fasoli, E1; Farinazzo, A1; Fiorini, M1; Gelati, M1; Iulini, B3; Tagliavini, F5; Ferrari, S1; Monaco, S1; Caramelli, M3; Capucci, L2 1University of Verona, Neurological and Visual Sciences, Italy; 2IZSLER, Italy; 3IZSPLVA, Italy; 4University of Turin, Animal Pathology, Italy; 5Isituto Carlo Besta, Italy
The clinical phenotype of bovine spongiform encephalopathy has been extensively reported in early accounts of the disorder. Following the introduction of statutory active surveillance, almost all BSE cases have been diagnosed on a pathological/molecular basis, in a pre-symptomatic clinical stage. In recent years, the active surveillance system has uncovered atypical BSE cases, which are characterized by distinct conformers of the PrPSc, named high-type (BSE-H) and low-type (BSE-L), whose clinicopathological phenotypes remain unknown. We recently reported two Italian atypical cases with a PrPSc type similar to BSE-L, pathologically characterized by PrP amyloid plaques. Experimental transmission to TgBov mice has recently disclosed that BASE is caused by a distinct prion strain which is extremely virulent. A major limitation of transmission studies to mice is the lack of reliable information on clinical phenotype of BASE in its natural host. In the present study, we experimentally infected Fresian/Holstein and Alpine/Brown cattle with Italian BSE and BASE isolates by i.c. route. BASE infected cattle showed survival times significantly shorter than BSE, a finding more readily evident in Fresian/Holstein, and in keeping with previous observations in TgBov mice. Clinically, BSE-infected cattle developed a disease phenotype highly comparable with that described in field BSE cases and in experimentally challenged cattle. On the contrary, BASE-inoculated cattle developed an amyotrophic disorder accompanied by mental dullness. The molecular and neuropathological profiles, including PrP deposition pattern, closely matched those observed in the original cases. 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.
Oral Abstracts 14
snip...
P04.27
Experimental BSE Infection of Non-human Primates: Efficacy of the Oral Route
Holznagel, E1; Yutzy, B1; Deslys, J-P2; Lasmézas, C2; Pocchiari, M3; Ingrosso, L3; Bierke, P4; Schulz-Schaeffer, W5; Motzkus, D6; Hunsmann, G6; Löwer, J1 1Paul-Ehrlich-Institut, Germany; 2Commissariat à l´Energie Atomique, France; 3Instituto Superiore di Sanità, Italy; 4Swedish Institute for Infectious Disease control, Sweden; 5Georg August University, Germany; 6German Primate Center, Germany
Background:
In 2001, a study was initiated in primates to assess the risk for humans to contract BSE through contaminated food. For this purpose, BSE brain was titrated in cynomolgus monkeys.
Aims:
The primary objective is the determination of the minimal infectious dose (MID50) for oral exposure to BSE in a simian model, and, by in doing this, to assess the risk for humans. Secondly, we aimed at examining the course of the disease to identify possible biomarkers.
Methods:
Groups with six monkeys each were orally dosed with lowering amounts of BSE brain: 16g, 5g, 0.5g, 0.05g, and 0.005g. In a second titration study, animals were intracerebrally (i.c.) dosed (50, 5, 0.5, 0.05, and 0.005 mg).
Results:
In an ongoing study, a considerable number of high-dosed macaques already developed simian vCJD upon oral or intracerebral exposure or are at the onset of the clinical phase. However, there are differences in the clinical course between orally and intracerebrally infected animals that may influence the detection of biomarkers.
Conclusions:
Simian vCJD can be easily triggered in cynomolgus monkeys on the oral route using less than 5 g BSE brain homogenate. The difference in the incubation period between 5 g oral and 5 mg i.c. is only 1 year (5 years versus 4 years). However, there are rapid progressors among orally dosed monkeys that develop simian v CJD as fast as intracerebrally inoculated animals.
The work referenced was performed in partial fulfilment of the study "BSE in primates" supported by the EU (QLK1-2002-01096).
http://www.prion2007.com/pdf/Prion%20Book%20of%20Abstracts.pdf
Subject: Aspects of the Cerebellar Neuropathology in Nor98
Date: September 26, 2007 at 4:06 pm PST
P03.141
Aspects of the Cerebellar Neuropathology in Nor98
Gavier-Widén, D1; Benestad, SL2; Ottander, L1; Westergren, E1 1National Veterinary Insitute, Sweden; 2National Veterinary Institute, Norway
Nor98 is a prion disease of old sheep and goats. This atypical form of scrapie was first described in Norway in 1998. Several features of Nor98 were shown to be different from classical scrapie including the distribution of disease associated prion protein (PrPd) accumulation in the brain. The cerebellum is generally the most affected brain area in Nor98. The study here presented aimed at adding information on the neuropathology in the cerebellum of Nor98 naturally affected sheep of various genotypes in Sweden and Norway. A panel of histochemical and immunohistochemical (IHC) stainings such as IHC for PrPd, synaptophysin, glial fibrillary acidic protein, amyloid, and cell markers for phagocytic cells were conducted. The type of histological lesions and tissue reactions were evaluated. The types of PrPd deposition were characterized. The cerebellar cortex was regularly affected, even though there was a variation in the severity of the lesions from case to case. Neuropil vacuolation was more marked in the molecular layer, but affected also the granular cell layer. There was a loss of granule cells. Punctate deposition of PrPd was characteristic. It was morphologically and in distribution identical with that of synaptophysin, suggesting that PrPd accumulates in the synaptic structures. PrPd was also observed in the granule cell layer and in the white matter.
*** The pathology features of Nor98 in the cerebellum of the affected sheep showed similarities with those of sporadic Creutzfeldt-Jakob disease in humans.
http://www.prion2007.com/pdf/Prion%20Book%20of%20Abstracts.pdf
SEE FULL TEXT ;
Creutzfeldt Jakob Disease Delaware UPDATE
http://cjdmadcowbaseoct2007.blogspot.com/2008/02/creutzfeldt-jakob-disease-delaware.html
Creutzfeldt Jakob Disease Texas
http://cjdtexas.blogspot.com/
USDA CERTIFIED H-BASE MAD COW SCHOOL LUNCH PROGRAM
http://cjdmadcowbaseoct2007.blogspot.com/2008/02/usda-certified-h-base-mad-cow-school.html
TSS
My point was that you hear something and don't get the full story and can't remember what you have said in the past. There are 10 cases of BSE in Canada and you freak out about it for a week with every new one then can't remember a thing about it when all you have to do is to go to the CFIA website and check facts. Is that soooo hard? 
