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Friday, November 09, 2018

Recombinant prion protein vaccination of transgenic elk PrP mice and reindeer overcomes self-tolerance and protects mice against chronic wasting disease

Recombinant prion protein vaccination of transgenic elk PrP mice and reindeer overcomes self-tolerance and protects mice against chronic wasting disease

Dalia. H. Abdelaziz1,2,3 *, Simrika Thapa1,3 *, Jenna Brandon1 , Justine Maybee1 , Lauren Vankuppeveld1 , Robert McCorkell1 and Hermann M. Schatzl1,3 

Running title: Vaccination protects against CWD. 

1 Department of Comparative Biology & Experimental Medicine, University of Calgary, Calgary, Alberta, Canada; 2 Department of Biochemistry and Molecular Biology, Faculty of Pharmacy, Helwan University, Cairo, Egypt 11795; 3 Calgary Prion Research Unit, University of Calgary, Calgary, Alberta, Canada. *authors equally contributed to the work. ¶ Corresponding author Email: hschaetz@ucalgary.ca (HMS); Address: Faculty of Veterinary Medicine University of Calgary, TRW 2D10, 3280 Hospital Drive NW, Calgary, AB, Canada T2N 4Z6 Phone: +1-403-210-6076

Key words: vaccination, chronic wasting disease, prion disease, prion, cervid prion protein, transgenic elk mice, neurodegeneration, Creutzfeldt-Jakob disease, immunization, brain disease.

Abstract

Chronic wasting disease (CWD) is a fatal neurodegenerative disease that affects cervids in North America and now Europe. No effective measures are available to control CWD. We hypothesized that active vaccination with homologous and aggregation-prone recombinant prion protein (PrP) could overcome self-tolerance and induce autoantibody production against the cellular isoform of PrP (PrPC), which would be protective against CWD infection from peripheral routes. Five groups of transgenic mice expressing elk PrP (TgElk) were vaccinated with either the adjuvant CpG alone or one of four recombinant PrP immunogens: deer dimer (Ddi), deer monomer (Dmo), mouse dimer (Mdi), and mouse monomer (Mmo). Mice were then challenged intraperitoneally with elk CWD prions. All vaccinated mice developed ELISA-detectable antibody titers against PrP. Importantly, all four vaccinated groups survived longer than the control group, with the Mmo-immunized group exhibiting 60% prolongation of mean survival time compared with the control group (183 vs. 114 days postinoculation). We tested for prion infection in brain and spleen of all clinically sick mice. Notably, the attack rate was 100% as revealed by positive CWD signals in all tested tissues when assessed with Western blotting, real-time quaking-induced conversion, and immunohistochemistry. Our pilot study in reindeers indicated appreciable humoral immune responses to Mdi and Ddi immunogens, and the post-immune sera from the Ddi vaccinated reindeer mitigated CWD propagation in a cell culture model (CWD-RK13). Taken together, our study provides very promising vaccine candidates against CWD, but further studies in cervids are required to investigate vaccine efficacy in the natural CWD hosts. 

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Discussion

Chronic wasting disease is a highly contagious and fatal neurodegenerative disease of cervids, which is found in North America, Korea and, more recently, in Europe. CWD affects farmed and free-ranging animals, and environmental components play a major role in disease transmission. This makes CWD very hard to control, and the disease is spreading geographically and in numbers in many parts of Northern America. It was shown that a high incidence of CWD negatively affects the population survival (37, 38). Although the zoonotic potential of CWD is currently considered low, data in nonhuman primates are conflicting for macaque transmissions (20, 39, 40), and infection by the oral route was clearly shown for new-world monkeys. A further alarming factor is that CWD prions are coming in different shapes and can undergo mutation-selection like processes (41–43). No effective therapies or vaccines are currently available to control CWD. The causative agent is the pathological and misfolded form of the endogenous host cellular prion protein (PrPSc), which does not elicit any detectable adaptive immune response due to having the same primary sequence as PrPC. This makes developing an effective vaccine against CWD very challenging, and most approaches aim for overcoming the selftolerance to PrP. On the other hand, such an approach involves the risk to induce unwanted side effects, and careful control for auto-immunity side effects have to be in place (44).

Only a few studies reported on the protective effect of a vaccination approach against CWD infection (30–32). Most of them were unsuccessful in achieving protection except one study by Goni and colleagues, which reported 25% protection in a white-tailed deer infection model, in form of prolongation of incubation time to disease. This study therefore provides a proof-of-concept for efficacy of a vaccination approach for containing CWD (31). This highlights the importance of our current study which describes a promising vaccination approach aiming at containing a fatal and so far, uncontrollable disease. In our previous work, we provided a proof-of-concept in wild-type and transgenic mouse models for the efficacy of mouse and deer recombinant PrPs, in both monomeric and dimeric forms, to break selftolerance and to induce self-antibodies against cellular PrP. Of note, post-immune sera were effective in inhibiting prion propagation in persistently prion-infected cell culture models, including CWD-infected RK13 cells (21, 29).

In this study, we extended our vaccination approach to transgenic mice expressing elk PrP (TgElk mice), which we challenged with elk CWD using the intraperitoneal route. All four immunogens induced again a substantial humoral immune response when testing for anti-PrP antibodies in ELISA. Mouse monomeric and dimeric recombinant PrPs showed the highest titers in ELISA, which can be explained by the non-self (mouse) nature of these immunogens. Despite the high sequence homology between mouse and deer PrP, there are more than 20 amino acids different between them which may help to provoke an adaptive immune response. The salient finding of our study is prolongation of survival in all groups of vaccinated TgElk mice after intraperitoneal CWD challenge, compared to CpG adjuvant-only control mice. Whereas our previous studies with mouse PrP in wild-type mice identified only a fraction of mice with prolongation of survival time (23), effects in this study pointed towards a group effect, although with some variability. The group vaccinated with Mmo immunogen displayed around 60% prolongation in mean survival which was the highest among all vaccinated groups. In line with this, sera of Mmovaccinated mice demonstrated the best detection of total elk PrP in immunoblots (data not shown). On the other hand, mice vaccinated with Mdi immunogen had only a 15.9% prolongation of mean survival time, although these sera were very reactive in ELISA and immunoblot. Obviously and in line with our previous results (21, 28, 29), there is no clear correlation with reactivity in ELISA and immunoblot, and protective behavior in prioninfected cell culture assays and mouse models. The groups immunized with Dmo and Ddi immunogens demonstrated extended mean survival times of 28.4% (median 57.1%) and 24.1% (median 29.7%), respectively. Interestingly, Ddi sera showed the weakest reactivity in ELISA. Somewhat unexpected, there was no difference among groups in terms of reactivity in the linear epitope mapping (data not shown).

One important beneficial aspect of CWD vaccination should be mitigation of peripheral shedding from infected animals. This aligns well with our experimental strategy, which wants to block prion propagation at peripheral sites of the body, outside the brain. We have started to monitor prion shedding in CWD-infected TgElk mice using RT-QuIC analysis from urine samples. Detection of prion infectivity in such excreta of infected TgElk mice has been challenging so far due to limited sample size and the fact that such transgenic mice do not well recapitulate prion pathogenesis and prion shedding as is characteristic for cervids. TgElk mice are homozygous for the elk PrP transgene and they can propagate CWD prions from deer and elk origin. Moreover, compared to other transgenic cervidized mouse models TgElk mice are characterized by a very short incubation time (95-120 days) upon CWD infection (33, 34). However, in previous studies using the TgElk mouse model infection was always done using the intracerebral route. Since our antibody approach targets PrPC as substrate of prion propagation outside the central nervous system, we had to use the intraperitoneal infection route to test the efficiency of our vaccination approach. In addition, intraperitoneal infection resembles natural routes of infection which usually occur through the alimentary tract. In our previous study we had i.p infected Tg(cerPrP)1536+/+ mice with cervid prions, which resulted in an incomplete attack rate (data not shown) which makes our data inconclusive. To the best of our knowledge this study is the first which characterizes i.p infection in TgElk mice. All inoculated mice demonstrated complete attack rate as shown by typical clinical signs, ranging from weight loss, kyphosis, very slow movement, rough coat to ataxia. These symptoms were in accordance with signs reported by Jeon and coworkers in this mouse line. The average incubation time for the control non-vaccinated group was 114 days which is longer than the i.c infection (90-95 days) reported in the previous studies (33, 34). This is expected, as i.p. infection is usually longer in incubation time than i.c. inoculation. Of note, due to the vaccination schedule our mice were 14-15 weeks older than i.c injected mice, which are usually between 4-6 weeks old when infected with prions. This might explain the broad range in incubation time.

To verify complete attack rate, we investigated the brains of all i.p. infected mice for signs of CWD infection using three different read-outs. RT-QuIC is a versatile technique for diagnosis of prion diseases including CWD (45). Although crude brain homogenates from all i.p. inoculated mice were positive in RT-QuIC, their signals were usually weaker than the ones of i.c. infected brain homogenates of the same mouse line. After NaPTA enrichment of PrPSc, all brain homogenates from i.p. infected mice showed strong signals comparable to that of i.c.-infected mice in both RTQuIC and immunoblotting. On the other hand, seeding activity in RT-QuIC of spleen homogenates of i.p.-infected mice was as high as found in i.c. infected spleen homogenates. Histologically, PrPSc deposition and vacuolation were detected with a pattern reminiscent of the pathological changes reported by LaFauci and colleagues in i.c.- inoculated TgElk mice. Whether there is a difference in the propagation of CWD in central vs. peripheral infection requires further analysis.

In our pilot study in reindeer, all Mdi-vaccinated reindeer showed appreciable antibody titers in ELISA. Yet, the response to Ddi as immunogen was only 33% (1 out of 3) in ELISA. The responding animal had 2 Prnp polymorphisms (225Y and 176D) which could explain the humoral immune response. However, better response to Ddi immunogen may be achievable by optimizing dose and timing of vaccination. So far, we used only one dose (500 µg/animal) and the schedule was not intense. Moreover, it is normal to find variation in vaccine responsiveness in a given population including some non-responders. Of note, we will do a recall experiment for the vaccinated reindeer with 2 more boosts after one year, to find out whether we are looking at non-response or a low response. Despite the comparatively low titer in ELISA, Ddi but not Mdi post-immune sera from reindeer were effective in neutralizing prion propagation in persistently CWD-infected RK13 cells. This indicates that superior binding to authentic and native cervid PrPC is achieved by self-antibodies in Ddi post-immune sera (Fig. 4C). In line with this, Mdi post-immune sera efficiently bound to mouse PrP but less efficiently to deer PrP when used as primary antibody in immunoblots. This comes in accordance with our previous data in which postimmune sera from Dmo-vaccinated tg(cerPrP)1536+/+ mice significantly reduced PrPSc propagation in CWD-infected RK13 cells. Our cell culture results indicate an improved efficiency of self-antibodies over cross-reactive antibodies in binding to native and authentic PrPC, which provides protection against conversion into PrPSc. However, in the current study we were not able to use Mmo and Dmo as immunogens due to the limited number of available reindeer for our study. We are aware of the fact that parenteral routes can be used for farmed animals and that the oral route is more realistic for vaccination of wild animals. Thus, we started encapsulating our immunogens in polylactic-co-glycolic acid microspheres which can be used orally (46). As an alternative approach, we also have initiated attempts to express PrP in plantbased systems.

In conclusion, our study provides very promising vaccine candidates against CWD, which were able to prolong the incubation time to disease by 60% in a transgenic mouse model. In addition, our pilot study in reindeer provided evidence for feasibility and efficacy of our vaccine approach in cervids. However, further studies are required to investigate the protective effect of the vaccine in cervids which are the natural hosts of chronic wasting disease. 



***> If slower disease progression results in longer-lived, infected deer with longer periods of infectiousness, resistance may lead to increased disease transmission rates, higher prion concentrations in the environment, and increased prevalence, as has been observed in some captive deer herds (Miller et al., 2006; Keane et al., 2008a). <***

Subject: cwd genetic susceptibility 

Genetic susceptibility to chronic wasting disease in free-ranging white-tailed deer: Complement component C1q and Prnp polymorphisms§ 

Julie A. Blanchong a, *, Dennis M. Heisey b , Kim T. Scribner c , Scot V. Libants d , Chad Johnson e , Judd M. Aiken e , Julia A. Langenberg f , Michael D. Samuel g

snip...

Identifying the genetic basis for heterogeneity in disease susceptibility or progression can improve our understanding of individual variation in disease susceptibility in both free-ranging and captive populations. What this individual variation in disease susceptibility means for the trajectory of disease in a population, however, is not straightforward. For example, the greater, but not complete, resistance to CWD in deer with at least one Serine (S) at amino acid 96 of the Prnp gene appears to be associated with slower progression of disease (e.g., Johnson et al., 2006; Keane et al., 2008a). If slower disease progression results in longer-lived, infected deer with longer periods of infectiousness, resistance may lead to increased disease transmission rates, higher prion concentrations in the environment, and increased prevalence, as has been observed in some captive deer herds (Miller et al., 2006; Keane et al., 2008a). Alternatively, if the slower progression of disease in resistant deer is not associated with longer periods of infectiousness, but might instead indicate a higher dose of PrPCWD is required for infection, transmission rates in the population could decline especially if, as in Wisconsin, deer suffer high rates of mortality from other sources (e.g., hunting). Clearly, determining the relationship between genetic susceptibility to infection, dose requirements, disease progression, and the period of PrPCWD infectiousness are key components for understanding the consequences of CWD to free-ranging populations.

http:// http://forest.wisc.edu/files/pdfs/samuel/2009%20blanchong%20et%20al%20genetic%20susceptibility%20chronic%20wasting.pdf

http://lib.dr.iastate.edu/cgi/viewcontent.cgi?article=1083&context=nrem_pubs

http://onlinelibrary.wiley.com/doi/10.2903/j.efsa.2017.4667/epdf

http://www.tandfonline.com/doi/full/10.1080/19336896.2015.1115179

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4964855/pdf/kprn-09-06-1115179.pdf

http://www.sciencedirect.com/science/article/pii/S1567134809001956?via=ihub 

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4964855/

***at present, no cervid PrP allele conferring absolute resistance to prion infection has been identified. 

P-145 Estimating chronic wasting disease resistance in cervids using real time quaking- induced conversion 

Nicholas J Haley1, Rachel Rielinqer2, Kristen A Davenport3, W. David Walter4, Katherine I O'Rourke5, Gordon Mitchell6, Juergen A Richt2 1 Department of Microbiology and Immunology, Midwestern University, United States; 2Department of Diagnostic Medicine and Pathobiology, Kansas State University; 3Prion Research Center; Colorado State University; 4U.S. Geological Survey, Pennsylvania Cooperative Fish and Wildlife Research Unit; 5Agricultural Research Service, United States Department of Agriculture; 6Canadian Food Inspection Agency, National and OlE Reference Laboratory for Scrapie and CWD 

In mammalian species, the susceptibility to prion diseases is affected, in part, by the sequence of the host's prion protein (PrP). In sheep, a gradation from scrapie susceptible to resistant has been established both in vivo and in vitro based on the amino acids present at PrP positions 136, 154, and 171, which has led to global breeding programs to reduce the prevalence of scrapie in domestic sheep. In cervids, resistance is commonly characterized as a delayed progression of chronic wasting disease (CWD); at present, no cervid PrP allele conferring absolute resistance to prion infection has been identified. To model the susceptibility of various naturally-occurring and hypothetical cervid PrP alleles in vitro, we compared the amplification rates and efficiency of various CWD isolates in recombinant PrPC using real time quaking-induced conversion. We hypothesized that amplification metrics of these isolates in cervid PrP substrates would correlate to in vivo susceptibility - allowing susceptibility prediction for alleles found at 10 frequency in nature, and that there would be an additive effect of multiple resistant codons in hypothetical alleles. Our studies demonstrate that in vitro amplification metrics predict in vivo susceptibility, and that alleles with multiple codons, each influencing resistance independently, do not necessarily contribute additively to resistance. Importantly, we found that the white-tailed deer 226K substrate exhibited the slowest amplification rate among those evaluated, suggesting that further investigation of this allele and its resistance in vivo are warranted to determine if absolute resistance to CWD is possible. 

***at present, no cervid PrP allele conferring absolute resistance to prion infection has been identified. 

PRION 2016 CONFERENCE TOKYO 

http://prion2016.org/dl/newsletter_03.pdf

============== 

''There are no known familial or genetic TSEs of animals, although polymorphisms in the PRNP gene of some species (sheep for example) may influence the length of the incubation period and occurrence of disease.'' 

=================

c) The commonest form of CJD occurs as a sporadic disease, the cause of which is unknown, although genetic factors (particularly the codon 129 polymorphism in the prion protein gene (PRNP)) influence disease susceptibility. The familial forms of human TSEs (see Box 1) appear to have a solely genetic origin and are closely associated with mutations or insertions in the PRNP gene. Most, but not all, of the familial forms of human TSEs have been transmitted experimentally to animals. There are no known familial or genetic TSEs of animals, although polymorphisms in the PRNP gene of some species (sheep for example) may influence the length of the incubation period and occurrence of disease. 

https://www.gov.uk/government/uploa...nt_data/file/209755/Part_1_-_Introduction.pdf

''There are no known familial or genetic TSEs of animals, although polymorphisms in the PRNP gene of some species (sheep for example) may influence the length of the incubation period and occurrence of disease.'' 

c) The commonest form of CJD occurs as a sporadic disease, the cause of which is unknown, although genetic factors (particularly the codon 129 polymorphism in the prion protein gene (PRNP)) influence disease susceptibility. The familial forms of human TSEs (see Box 1) appear to have a solely genetic origin and are closely associated with mutations or insertions in the PRNP gene. Most, but not all, of the familial forms of human TSEs have been transmitted experimentally to animals. There are no known familial or genetic TSEs of animals, although polymorphisms in the PRNP gene of some species (sheep for example) may influence the length of the incubation period and occurrence of disease. 

https://www.gov.uk/government/uploa...nt_data/file/209755/Part_1_-_Introduction.pdf

RESEARCH ARTICLE

Haley et al., Journal of General Virology 2017;98:2882–2892

DOI 10.1099/jgv.0.000952

Estimating chronic wasting disease susceptibility in cervids using real-time quaking-induced conversion

Nicholas J. Haley,1, * Rachel Rielinger,2 Kristen A. Davenport,3 Katherine O’Rourke,4 Gordon Mitchell5 and Jürgen A. Richt2

Abstract

In mammals, susceptibility to prion infection is primarily modulated by the host’s cellular prion protein (PrPC ) sequence. In the sheep scrapie model, a graded scale of susceptibility has been established both in vivo and in vitro based on PrPC amino acids 136, 154 and 171, leading to global breeding programmes to reduce the prevalence of scrapie in sheep. 

Chronic wasting disease (CWD) resistance in cervids is often characterized as decreased prevalence and/or protracted disease progression in individuals with specific alleles; at present, no PrPC allele conferring absolute resistance in cervids has been identified. 

To model the susceptibility of various naturally occurring and hypothetical cervid PrPC alleles in vitro, we compared the amplification rates and amyloid extension efficiencies of eight distinct CWD isolates in recombinant cervid PrPC substrates using real-time quaking-induced conversion. 

We hypothesized that the in vitro conversion characteristics of these isolates in cervid substrates would correlate to in vivo susceptibility – permitting susceptibility prediction for the rare alleles found in nature. 

We also predicted that hypothetical alleles with multiple resistance-associated codons would be more resistant to in vitro conversion than natural alleles with a single resistant codon. 

Our studies demonstrate that in vitro conversion metrics align with in vivo susceptibility, and that alleles with multiple amino acid substitutions, each influencing resistance independently, do not necessarily contribute additively to conversion resistance. 

Importantly, we found that the naturally occurring whitetail deer QGAK substrate exhibited the slowest amplification rate among those evaluated, suggesting that further investigation of this allele and its resistance in vivo is warranted.

INTRODUCTION

Chronic wasting disease (CWD) is an efficiently transmitted spongiform encephalopathy of cervids (e.g. deer, elk and moose), and is the only known prion disease affecting both farmed and free-ranging, non-domestic animals [1]. The disease is naturally occurring in white-tailed deer (Odocoileus virginianus), mule deer (Odocoileus hemionus), North American elk (Cervus elaphus nelsoni), moose (Alces alces) and reindeer (Rangifer tarandus), and may be experimentally transmitted to a range of experimental species [2–5]. CWD has now been reported in 24 US states, two Canadian provinces, the Republic of Korea and, most recently, Norway [6, 7].

Within individual cervid species, evidence of CWD resistance – which manifests as decreased prevalence and/or delayed progression of disease – has been reported [8–15]. The resistance mechanisms are incompletely understood, but are thought to depend primarily on the host’s cellular prion protein (PrPC ) amino acid sequence, encoded by the PRNP gene [16]. In white-tailed deer, much emphasis has been placed on variations at PrPC position 96 (glycine, G or serine, S), as it is one of the most common polymorphisms found in nature and has repeatedly been linked to susceptibility. The resistant 96S allele has a frequency of roughly 20 % in white-tailed deer populations of North America, a frequency which varies somewhat in both farmed and free ranging populations. Other codon variations with significantly lower allelic frequency have been identified that have not been systematically evaluated for resistance, including codons 95 (histidine, H, versus wild-type glutamine, Q), 116 (glycine versus wild-type alanine, A) and 226 (lysine, K, versus wild-type glutamine) [11]. Because of their low frequencies, the manifestations of CWD in these alleles (notably in their homozygous state) have not been well studied. In elk, the expression of leucine (L) at codon 132 appears to confer CWD resistance when compared to the more prevalent 132M allele [15, 17–19], while in mule deer, lower CWD prevalence has been reported in animals expressing a phenylalanine (F) at codon 225, versus the wild-type 225S [20, 21]. It is possible that other, as yet undiscovered, alleles (including loss of function mutations) may affect resistance in deer and elk. Resistance in other cervid species has not been well-characterized to date, although studies in a limited number of fallow deer and reindeer have shown that variations from the wild-type PRNP allele likely affect susceptibility [22–25].

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DISCUSSION

Among mammalian prion diseases, CWD of cervids has proven to be one of the most problematic to control. While halting the practice of feeding meat and bone meal Table 1. in 1994 effectively curbed the bovine spongiform encephalopathy (BSE) epidemic, and selective breeding in domestic sheep herds has reduced the prevalence of scrapie by 90 % or more [34–37], an effective management strategy for CWD in farmed and free-ranging cervid herds has proven elusive. In contrast to BSE, CWD is spread quite effectively between cervids through excreta and environmental contamination [6]. Unlike sheep scrapie, no allele or allelic pairing has been found that completely prevents CWD infection in deer and elk species. An important limitation in the search for CWD-resistant cervids is the relative rarity of resistant PRNP alleles. In many cases it is exceedingly uncommon to find these alleles in the homozygous state, somewhat obscuring field studies of the influence of genetics on CWD susceptibility and making their inclusion in challenge studies problematic. The present study sought to examine the misfolding propensities of these rare alleles in vitro, in the hope that our findings might help target specific alleles for further examination in future challenge studies.

We first hypothesized that two metrics of in vitro amplification – rate and efficiency – would parallel in vivo susceptibility across cervid species. Indeed, our findings demonstrate that these two metrics, acting in concert, seem to follow in vivo susceptibility in cervids. The metric that seemed to align most with in vivo susceptibility was the rate of amplification, which likely represents PrPres seed–PrPC substrate compatibility, and the ability of the substrate to form the initial PrPres species. Amyloid extension efficiency may further separate those substrates with statistically similar amplification rates, and likely indicates the capacity of the amyloid product to serve as a seed for amyloid growth, an important step in prion propagation. While the true contributions of these metrics to susceptibility in natural hosts are almost certainly more intricate, our findings suggest that whitetailed deer allele QGGQ, with a limited number of field cases examined, may not be as resistant in nature as it appears – based on rapid amplification rates when seeded with several geographically distinct CWD isolates. Meanwhile, alleles from three different cervid species with similarly low numbers of field cases – 225F in mule deer, QGAK in whitetailed deer and 225Y in reindeer (all found in the Helix 3 domain of PrPC ) – demonstrated significantly reduced rates of amplification across multiple CWD isolates and seed dilutions, and warrant further exploration of resistance in the natural host.

Challenge studies in cervid species to estimate susceptibility have so far been limited, and have yet to systematically evaluate alleles other than QSAQ. While field studies under presumably natural conditions have found that CWD-positive 225F mule deer are incredibly uncommon [20, 21], one study involving a small number of orally challenged 225F homozygous mule deer has been reported [8]. These animals were found to have some level of resistance, indicated by prolonged incubation times, although they also presented potential diagnostic challenges based on an unusual neuropathology. Rare challenge studies have also been undertaken in other species – including both fallow deer and reindeer [22–25]. Fallow deer, expressing the 138N/226E allele, appear to be completely resistant to experimental challenge [22–25], while bioassays in a limited number of reindeer have shown that animals that are heterozygous for QGAQ/ 225Y, QGAQ/138N and QGAQ/SSM alleles may be more resistant than QGAQ homozygous animals. With the discovery of CWD in Norwegian reindeer in 2016 [7], field studies allowing further comparisons of their susceptibility may soon be available following a planned herd reduction over the coming year [38].

We next hypothesized that there would be an additive effect towards delayed amplification rates and/or reduced extension efficiencies in substrates with multiple PrPC mutations associated with natural CWD resistance, based on the additive effects of multiple resistance-associated codons seen in sheep scrapie (e.g. 136V/154R/171Q homozygotes vs 136A/ 154R/171Q homozygotes vs 136A/154R/171R homozygotes vs heterozygotes of these three alleles) [34, 39–42]. Across CWD isolates, in vitro amplification data in most hypothetical white-tailed deer alleles with multiple mutations showed that this was not the case, with variants commonly demonstrating amplification rates that were comparable to those for QGAQ or naturally occurring alleles with a single mutation. Three proteins (QGGK, HSAQ and HSAK), however, consistently showed significantly reduced rates of amplification, similar to the poorly amplifying QGAK protein. The extension efficiency in these proteins was commonly greater than that of the wild-type QGAQ, a finding that is observed most often in the HSAK substrate. Our examinations with these hypothetical substrates assumed that the various mutations could be found stacked on the same allele (as reported for sheep PRNP variants) – modelling homozygosity in a cervid host. We did not evaluate outcomes from a balanced titration of two white-tailed deer alleles acting together in vitro, however, to model a heterozygous state appropriately (QGGQ QSAQ, for example). Future experiments examining these permutations may show more clearly the potential for altered susceptibility in cervids that are heterozygous for two different resistance-associated alleles, where the two proteins may act synergistically in vivo to either limit or enhance CWD pathogenesis.

While our experiments were used to ascertain the amplification abilities of various substrates seeded with a specific CWD isolate, we could not examine potential amplification differences between isolates effectively. It would be very tempting to try to draw conclusions from the interisolate variability seen among substrates, but a proper approach to answer this question would require well-controlled seeding with a known dose of PrPSc seed across isolates. This may be possible by adjusting seed concentrations to consistent amplification rates in a mutually dissimilar substrate (e.g. truncated Syrian hamster PrPC ) or through bioassay titration. Were it possible to overcome this obstacle, it seems plausible that RT-QuIC amplification could be used to examine PrPSc strain typing rigorously, as there is some evidence that several strains may be circulating in cervids [43–45]. This may, in turn, permit a better understanding of the recent source of CWD introductions in North America and Europe.

In summary, evaluating the amplification rates and efficiencies of recombinant PrPC substrates by RT-QuIC could be a useful tool for estimating the susceptibility of rare or newly discovered PRNP alleles, allowing researchers to target specific alleles for downstream evaluation in challenge studies. In the face of an ever-expanding CWD-endemic area, it is increasingly important to characterize the natural susceptibility of these alleles, as well as their geographical distribution and the evolutionary basis for their rarity. Do the QGAK, 225F and 225Y alleles represent recent, random anomalies, or are they more primitive mutations that adversely affect reproductive fitness? Perhaps they are an indication that cervids with these rare alleles were themselves once the target of a primordial prion strain. While some evidence has been presented for distinct strains of CWD, little is known about their geographical distribution or virulence in cervid hosts of diverse PRNP backgrounds. It is possible that, with the appropriate framework, RTQuIC could allow for the discrimination of known and novel prion strains. Without further research into disease management and prevention, including resistance, the only certainty seems to be that CWD will continue its insidious spread, with further discoveries in new hosts and geographical locations. 


Scientific opinion on chronic wasting disease (II)

EFSA Panel on Biological Hazards (BIOHAZ) Antonia Ricci Ana Allende Declan Bolton Marianne Chemaly Robert Davies Pablo Salvador Fernández Escámez … 

See all authors 

First published: 17 January 2018 https://doi.org/10.2903/j.efsa.2018.5132


the tse prion aka mad cow type disease is not your normal pathogen. 

The TSE prion disease survives ashing to 600 degrees celsius, that’s around 1112 degrees farenheit. 

you cannot cook the TSE prion disease out of meat. 

you can take the ash and mix it with saline and inject that ash into a mouse, and the mouse will go down with TSE. 

Prion Infected Meat-and-Bone Meal Is Still Infectious after Biodiesel Production as well. 

the TSE prion agent also survives Simulated Wastewater Treatment Processes. 

IN fact, you should also know that the TSE Prion agent will survive in the environment for years, if not decades. 

you can bury it and it will not go away. 

The TSE agent is capable of infected your water table i.e. Detection of protease-resistant cervid prion protein in water from a CWD-endemic area. 

it’s not your ordinary pathogen you can just cook it out and be done with. 

***> that’s what’s so worrisome about Iatrogenic mode of transmission, a simple autoclave will not kill this TSE prion agent.


this old study next always stuns me. think of this the next time you clean your tools you use to gut and bone out your kill, and then feeding it to your family and friends...tss


1: J Neurol Neurosurg Psychiatry 1994 Jun;57(6):757-8 

***> Transmission of Creutzfeldt-Jakob disease to a chimpanzee by electrodes contaminated during neurosurgery. 

Gibbs CJ Jr, Asher DM, Kobrine A, Amyx HL, Sulima MP, Gajdusek DC. 

Laboratory of Central Nervous System Studies, National Institute of 

Neurological Disorders and Stroke, National Institutes of Health, 

Bethesda, MD 20892. 

Stereotactic multicontact electrodes used to probe the cerebral cortex of a middle aged woman with progressive dementia were previously implicated in the accidental transmission of Creutzfeldt-Jakob disease (CJD) to two younger patients. The diagnoses of CJD have been confirmed for all three cases. More than two years after their last use in humans, after three cleanings and repeated sterilisation in ethanol and formaldehyde vapour, the electrodes were implanted in the cortex of a chimpanzee. Eighteen months later the animal became ill with CJD. This finding serves to re-emphasise the potential danger posed by reuse of instruments contaminated with the agents of spongiform encephalopathies, even after scrupulous attempts to clean them. 

PMID: 8006664 [PubMed - indexed for MEDLINE] 


Infectious agent of sheep scrapie may persist in the environment for at least 16 years

Gudmundur Georgsson,1 Sigurdur Sigurdarson2 and Paul Brown3

Correspondence

Gudmundur Georgsson ggeorgs@hi.is

1 Institute for Experimental Pathology, University of Iceland, Keldur v/vesturlandsveg, IS-112 Reykjavı´k, Iceland

2 Laboratory of the Chief Veterinary Officer, Keldur, Iceland

3 Bethesda, Maryland, USA

Received 7 March 2006 Accepted 6 August 2006

In 1978, a rigorous programme was implemented to stop the spread of, and subsequently eradicate, sheep scrapie in Iceland. Affected flocks were culled, premises were disinfected and, after 2–3 years, restocked with lambs from scrapie-free areas. Between 1978 and 2004, scrapie recurred on 33 farms. Nine of these recurrences occurred 14–21 years after culling, apparently as the result of environmental contamination, but outside entry could not always be absolutely excluded. Of special interest was one farm with a small, completely self-contained flock where scrapie recurred 18 years after culling, 2 years after some lambs had been housed in an old sheephouse that had never been disinfected. Epidemiological investigation established with near certitude that the disease had not been introduced from the outside and it is concluded that the agent may have persisted in the old sheep-house for at least 16 years.


21 YEARS!

***>>>Nine of these recurrences occurred 14–21 years after culling, apparently as the result of environmental contamination, but outside entry could not always be absolutely excluded...

ALSO SEE;

***>>> Recently, we have been using PMCA to study the role of environmental prion contamination on the horizontal spreading of TSEs. These experiments have focused on the study of the interaction of prions with plants and environmentally relevant surfaces. Our results show that plants (both leaves and roots) bind tightly to prions present in brain extracts and excreta (urine and feces) and retain even small quantities of PrPSc for long periods of time. Strikingly, ingestion of prion contaminated leaves and roots produced disease with a 100% attack rate and an incubation period not substantially longer than feeding animals directly with scrapie brain homogenate. Furthermore, plants can uptake prions from contaminated soil and transport them to different parts of the plant tissue (stem and leaves). Similarly, prions bind tightly to a variety of environmentally relevant surfaces, including stones, wood, metals, plastic, glass, cement, etc. Prion contaminated surfaces efficiently transmit prion disease when these materials were directly injected into the brain of animals and strikingly when the contaminated surfaces were just placed in the animal cage. These findings demonstrate that environmental materials can efficiently bind infectious prions and act as carriers of infectivity, suggesting that they may play an important role in the horizontal transmission of the disease.

========================

Since its invention 13 years ago, PMCA has helped to answer fundamental questions of prion propagation and has broad applications in research areas including the food industry, blood bank safety and human and veterinary disease diagnosis. 


New studies on the heat resistance of hamster-adapted scrapie agent: Threshold survival after ashing at 600°C suggests an inorganic template of replication 


Prion Infected Meat-and-Bone Meal Is Still Infectious after Biodiesel Production 


Detection of protease-resistant cervid prion protein in water from a CWD-endemic area 


A Quantitative Assessment of the Amount of Prion Diverted to Category 1 Materials and Wastewater During Processing 


Rapid assessment of bovine spongiform encephalopathy prion inactivation by heat treatment in yellow grease produced in the industrial manufacturing process of meat and bone meals 


PPo4-4: 

Survival and Limited Spread of TSE Infectivity after Burial 



***> CONGRESSIONAL ABSTRACTS PRION CONFERENCE 2018

P69 Experimental transmission of CWD from white-tailed deer to co-housed reindeer 

Mitchell G (1), Walther I (1), Staskevicius A (1), Soutyrine A (1), Balachandran A (1) 

(1) National & OIE Reference Laboratory for Scrapie and CWD, Canadian Food Inspection Agency, Ottawa, Ontario, Canada. 

Chronic wasting disease (CWD) continues to be detected in wild and farmed cervid populations of North America, affecting predominantly white-tailed deer, mule deer and elk. Extensive herds of wild caribou exist in northern regions of Canada, although surveillance has not detected the presence of CWD in this population. Oral experimental transmission has demonstrated that reindeer, a species closely related to caribou, are susceptible to CWD. Recently, CWD was detected for the first time in Europe, in wild Norwegian reindeer, advancing the possibility that caribou in North America could also become infected. Given the potential overlap in habitat between wild CWD-infected cervids and wild caribou herds in Canada, we sought to investigate the horizontal transmissibility of CWD from white-tailed deer to reindeer. 

Two white-tailed deer were orally inoculated with a brain homogenate prepared from a farmed Canadian white-tailed deer previously diagnosed with CWD. Two reindeer, with no history of exposure to CWD, were housed in the same enclosure as the white-tailed deer, 3.5 months after the deer were orally inoculated. The white-tailed deer developed clinical signs consistent with CWD beginning at 15.2 and 21 months post-inoculation (mpi), and were euthanized at 18.7 and 23.1 mpi, respectively. Confirmatory testing by immunohistochemistry (IHC) and western blot demonstrated widespread aggregates of pathological prion protein (PrPCWD) in the central nervous system and lymphoid tissues of both inoculated white-tailed deer. Both reindeer were subjected to recto-anal mucosal associated lymphoid tissue (RAMALT) biopsy at 20 months post-exposure (mpe) to the white-tailed deer. The biopsy from one reindeer contained PrPCWD confirmed by IHC. This reindeer displayed only subtle clinical evidence of disease prior to a rapid decline in condition requiring euthanasia at 22.5 mpe. Analysis of tissues from this reindeer by IHC revealed widespread PrPCWD deposition, predominantly in central nervous system and lymphoreticular tissues. Western blot molecular profiles were similar between both orally inoculated white-tailed deer and the CWD positive reindeer. Despite sharing the same enclosure, the other reindeer was RAMALT negative at 20 mpe, and PrPCWD was not detected in brainstem and lymphoid tissues following necropsy at 35 mpe. Sequencing of the prion protein gene from both reindeer revealed differences at several codons, which may have influenced susceptibility to infection. 

Natural transmission of CWD occurs relatively efficiently amongst cervids, supporting the expanding geographic distribution of disease and the potential for transmission to previously naive populations. The efficient horizontal transmission of CWD from white-tailed deer to reindeer observed here highlights the potential for reindeer to become infected if exposed to other cervids or environments infected with CWD. 




TITLE: PATHOLOGICAL FEATURES OF CHRONIC WASTING DISEASE IN REINDEER AND DEMONSTRATION OF HORIZONTAL TRANSMISSION 



 *** DECEMBER 2016 CDC EMERGING INFECTIOUS DISEASE JOURNAL CWD HORIZONTAL TRANSMISSION 


Using in vitro Prion replication for high sensitive detection of prions and prionlike proteins and for understanding mechanisms of transmission. 

Claudio Soto Mitchell Center for Alzheimer's diseases and related Brain disorders, Department of Neurology, University of Texas Medical School at Houston. 

Prion and prion-like proteins are misfolded protein aggregates with the ability to selfpropagate to spread disease between cells, organs and in some cases across individuals. I n T r a n s m i s s i b l e s p o n g i f o r m encephalopathies (TSEs), prions are mostly composed by a misfolded form of the prion protein (PrPSc), which propagates by transmitting its misfolding to the normal prion protein (PrPC). The availability of a procedure to replicate prions in the laboratory may be important to study the mechanism of prion and prion-like spreading and to develop high sensitive detection of small quantities of misfolded proteins in biological fluids, tissues and environmental samples. Protein Misfolding Cyclic Amplification (PMCA) is a simple, fast and efficient methodology to mimic prion replication in the test tube. PMCA is a platform technology that may enable amplification of any prion-like misfolded protein aggregating through a seeding/nucleation process. In TSEs, PMCA is able to detect the equivalent of one single molecule of infectious PrPSc and propagate prions that maintain high infectivity, strain properties and species specificity. Using PMCA we have been able to detect PrPSc in blood and urine of experimentally infected animals and humans affected by vCJD with high sensitivity and specificity. Recently, we have expanded the principles of PMCA to amplify amyloid-beta (Aβ) and alphasynuclein (α-syn) aggregates implicated in Alzheimer's and Parkinson's diseases, respectively. Experiments are ongoing to study the utility of this technology to detect Aβ and α-syn aggregates in samples of CSF and blood from patients affected by these diseases.

=========================

***>>> Recently, we have been using PMCA to study the role of environmental prion contamination on the horizontal spreading of TSEs. These experiments have focused on the study of the interaction of prions with plants and environmentally relevant surfaces. Our results show that plants (both leaves and roots) bind tightly to prions present in brain extracts and excreta (urine and feces) and retain even small quantities of PrPSc for long periods of time. Strikingly, ingestion of prioncontaminated leaves and roots produced disease with a 100% attack rate and an incubation period not substantially longer than feeding animals directly with scrapie brain homogenate. Furthermore, plants can uptake prions from contaminated soil and transport them to different parts of the plant tissue (stem and leaves). Similarly, prions bind tightly to a variety of environmentally relevant surfaces, including stones, wood, metals, plastic, glass, cement, etc. Prion contaminated surfaces efficiently transmit prion disease when these materials were directly injected into the brain of animals and strikingly when the contaminated surfaces were just placed in the animal cage. These findings demonstrate that environmental materials can efficiently bind infectious prions and act as carriers of infectivity, suggesting that they may play an important role in the horizontal transmission of the disease.

========================

Since its invention 13 years ago, PMCA has helped to answer fundamental questions of prion propagation and has broad applications in research areas including the food industry, blood bank safety and human and veterinary disease diagnosis. 


Discussion Classical scrapie is an environmentally transmissible disease because it has been reported in naïve, supposedly previously unexposed sheep placed in pastures formerly occupied by scrapie-infected sheep (4, 19, 20). 

Although the vector for disease transmission is not known, soil is likely to be an important reservoir for prions (2) where – based on studies in rodents – prions can adhere to minerals as a biologically active form (21) and remain infectious for more than 2 years (22). 

Similarly, chronic wasting disease (CWD) has re-occurred in mule deer housed in paddocks used by infected deer 2 years earlier, which was assumed to be through foraging and soil consumption (23). 

Our study suggested that the risk of acquiring scrapie infection was greater through exposure to contaminated wooden, plastic, and metal surfaces via water or food troughs, fencing, and hurdles than through grazing. 

Drinking from a water trough used by the scrapie flock was sufficient to cause infection in sheep in a clean building. 

Exposure to fences and other objects used for rubbing also led to infection, which supported the hypothesis that skin may be a vector for disease transmission (9). 

The risk of these objects to cause infection was further demonstrated when 87% of 23 sheep presented with PrPSc in lymphoid tissue after grazing on one of the paddocks, which contained metal hurdles, a metal lamb creep and a water trough in contact with the scrapie flock up to 8 weeks earlier, whereas no infection had been demonstrated previously in sheep grazing on this paddock, when equipped with new fencing and field furniture. 

When the contaminated furniture and fencing were removed, the infection rate dropped significantly to 8% of 12 sheep, with soil of the paddock as the most likely source of infection caused by shedding of prions from the scrapie-infected sheep in this paddock up to a week earlier. 

This study also indicated that the level of contamination of field furniture sufficient to cause infection was dependent on two factors: stage of incubation period and time of last use by scrapie-infected sheep. 

Drinking from a water trough that had been used by scrapie sheep in the predominantly pre-clinical phase did not appear to cause infection, whereas infection was shown in sheep drinking from the water trough used by scrapie sheep in the later stage of the disease. 

It is possible that contamination occurred through shedding of prions in saliva, which may have contaminated the surface of the water trough and subsequently the water when it was refilled. 

Contamination appeared to be sufficient to cause infection only if the trough was in contact with sheep that included clinical cases. 

Indeed, there is an increased risk of bodily fluid infectivity with disease progression in scrapie (24) and CWD (25) based on PrPSc detection by sPMCA. 

Although ultraviolet light and heat under natural conditions do not inactivate prions (26), furniture in contact with the scrapie flock, which was assumed to be sufficiently contaminated to cause infection, did not act as vector for disease if not used for 18 months, which suggest that the weathering process alone was sufficient to inactivate prions. 

PrPSc detection by sPMCA is increasingly used as a surrogate for infectivity measurements by bioassay in sheep or mice. 

In this reported study, however, the levels of PrPSc present in the environment were below the limit of detection of the sPMCA method, yet were still sufficient to cause infection of in-contact animals. 

In the present study, the outdoor objects were removed from the infected flock 8 weeks prior to sampling and were positive by sPMCA at very low levels (2 out of 37 reactions). 

As this sPMCA assay also yielded 2 positive reactions out of 139 in samples from the scrapie-free farm, the sPMCA assay could not detect PrPSc on any of the objects above the background of the assay. 

False positive reactions with sPMCA at a low frequency associated with de novo formation of infectious prions have been reported (27, 28). 

This is in contrast to our previous study where we demonstrated that outdoor objects that had been in contact with the scrapie-infected flock up to 20 days prior to sampling harbored PrPSc that was detectable by sPMCA analysis [4 out of 15 reactions (12)] and was significantly more positive by the assay compared to analogous samples from the scrapie-free farm. 

This discrepancy could be due to the use of a different sPMCA substrate between the studies that may alter the efficiency of amplification of the environmental PrPSc. 

In addition, the present study had a longer timeframe between the objects being in contact with the infected flock and sampling, which may affect the levels of extractable PrPSc. 

Alternatively, there may be potentially patchy contamination of this furniture with PrPSc, which may have been missed by swabbing. 

The failure of sPMCA to detect CWD-associated PrP in saliva from clinically affected deer despite confirmation of infectivity in saliva-inoculated transgenic mice was associated with as yet unidentified inhibitors in saliva (29), and it is possible that the sensitivity of sPMCA is affected by other substances in the tested material. 

In addition, sampling of amplifiable PrPSc and subsequent detection by sPMCA may be more difficult from furniture exposed to weather, which is supported by the observation that PrPSc was detected by sPMCA more frequently in indoor than outdoor furniture (12). 

A recent experimental study has demonstrated that repeated cycles of drying and wetting of prion-contaminated soil, equivalent to what is expected under natural weathering conditions, could reduce PMCA amplification efficiency and extend the incubation period in hamsters inoculated with soil samples (30). 

This seems to apply also to this study even though the reduction in infectivity was more dramatic in the sPMCA assays than in the sheep model. 

Sheep were not kept until clinical end-point, which would have enabled us to compare incubation periods, but the lack of infection in sheep exposed to furniture that had not been in contact with scrapie sheep for a longer time period supports the hypothesis that prion degradation and subsequent loss of infectivity occurs even under natural conditions. 

In conclusion, the results in the current study indicate that removal of furniture that had been in contact with scrapie-infected animals should be recommended, particularly since cleaning and decontamination may not effectively remove scrapie infectivity (31), even though infectivity declines considerably if the pasture and the field furniture have not been in contact with scrapie-infected sheep for several months. As sPMCA failed to detect PrPSc in furniture that was subjected to weathering, even though exposure led to infection in sheep, this method may not always be reliable in predicting the risk of scrapie infection through environmental contamination. 

These results suggest that the VRQ/VRQ sheep model may be more sensitive than sPMCA for the detection of environmentally associated scrapie, and suggest that extremely low levels of scrapie contamination are able to cause infection in susceptible sheep genotypes. 

Keywords: classical scrapie, prion, transmissible spongiform encephalopathy, sheep, field furniture, reservoir, serial protein misfolding cyclic amplification 


Wednesday, December 16, 2015 

*** Objects in contact with classical scrapie sheep act as a reservoir for scrapie transmission *** 



ALSO, I FIND THIS VERY DISTURBING...SEE;


***> Prion 2018 P74 High Prevalence of CWD prions in male reproductive samples 

Carlos Kramm (1,2), Ruben Gomez-Gutierrez (1,3), Tracy Nichols (4), Claudio Soto (1) and Rodrigo Morales (1) 


READING OVER THE PRION 2018 ABSTRACT BOOK, LOOKS LIKE THEY FOUND THAT Protein Misfolding Cyclic Amplification PMCA results showed positive CWD prion detection in testes, epididymis and seminal fluid samples. seems also the scientists are worried about any potential mechanisms of CWD spreading and they want to decrease putative interindividual transmission associated to insemination using CWD contaminated specimens, if that might occur under natural conditions. i have been concerned about this for some time with BSE super-ovulation and since;

 PrPSc detection and infectivity in semen from scrapie-infected sheep




PITUITARY EXTRACT

This was used to help cows super ovulate. This tissue was considered to be of greatest risk of containing BSE and consequently transmitting the disease...








MANAGEMENT IN CONFIDENCE

CERTIFIED BSE-FREE HERDS FOR SOURCE OF MATERIAL FOR BIOLOGICAL PRODUCTS



Tuesday, February 8, 2011

U.S.A. 50 STATE BSE MAD COW CONFERENCE CALL Jan. 9, 2001



HAVE YOU BEEN THUNDERSTRUCK? 

SUNDAY, AUGUST 02, 2015 

TEXAS CWD, Have you been ThunderStruck, deer semen, straw bred bucks, super ovulation, and the potential TSE Prion connection, what if?

Court papers state that in February 2007, Favero acquired 184 straws of whitetail deer semen valued at about $92,000 from a buck named “Diablo'” that he knew had been illegally taken out of Texas, and again in January 2008 took another 110 straws of semen from a buck named “Thunderstruck.” (Read more in the court paper posted at the bottom of this entry.)





SUNDAY, AUGUST 19, 2018 

Texas Deer Farms, Growing Freakish Antlers, and CWD TSE Prion aka mad deer disease



FRIDAY, MARCH 30, 2018 

Docket No. APHIS-2018-0011 Chronic Wasting Disease Herd Certification Program Standards Singeltary Submission March 30, 2018

Terry S. Singeltary Sr., Bacliff, Texas USA 77518 flounder9@verizon....net 

Attachments (1) Docket No. APHIS-2018-0011 Chronic Wasting Disease Herd Certification Program Standards Singeltary View Attachment:View as format pdf 



https://www.regulations.gov/docketBrowser?rpp=25&so=DESC&sb=commentDueDate&po=0&dct=PS&D=APHIS-2018-0011



Friday, December 14, 2012

DEFRA U.K. What is the risk of Chronic Wasting Disease CWD being introduced into Great Britain? A Qualitative Risk Assessment October 2012

snip.....

In the USA, under the Food and Drug Administration's BSE Feed Regulation (21 CFR 589.2000) most material (exceptions include milk, tallow, and gelatin) from deer and elk is prohibited for use in feed for ruminant animals. With regards to feed for non-ruminant animals, under FDA law, CWD positive deer may not be used for any animal feed or feed ingredients. For elk and deer considered at high risk for CWD, the FDA recommends that these animals do not enter the animal feed system. However, this recommendation is guidance and not a requirement by law.

Animals considered at high risk for CWD include:

1) animals from areas declared to be endemic for CWD and/or to be CWD eradication zones and

2) deer and elk that at some time during the 60-month period prior to slaughter were in a captive herd that contained a CWD-positive animal.

Therefore, in the USA, materials from cervids other than CWD positive animals may be used in animal feed and feed ingredients for non-ruminants.

The amount of animal PAP that is of deer and/or elk origin imported from the USA to GB can not be determined, however, as it is not specified in TRACES. It may constitute a small percentage of the 8412 kilos of non-fish origin processed animal proteins that were imported from US into GB in 2011.

Overall, therefore, it is considered there is a __greater than negligible risk___ that (nonruminant) animal feed and pet food containing deer and/or elk protein is imported into GB.

There is uncertainty associated with this estimate given the lack of data on the amount of deer and/or elk protein possibly being imported in these products.

snip.....

36% in 2007 (Almberg et al., 2011). In such areas, population declines of deer of up to 30 to 50% have been observed (Almberg et al., 2011). In areas of Colorado, the prevalence can be as high as 30% (EFSA, 2011).

The clinical signs of CWD in affected adults are weight loss and behavioural changes that can span weeks or months (Williams, 2005). In addition, signs might include excessive salivation, behavioural alterations including a fixed stare and changes in interaction with other animals in the herd, and an altered stance (Williams, 2005). These signs are indistinguishable from cervids experimentally infected with bovine spongiform encephalopathy (BSE).

Given this, if CWD was to be introduced into countries with BSE such as GB, for example, infected deer populations would need to be tested to differentiate if they were infected with CWD or BSE to minimise the risk of BSE entering the human food-chain via affected venison.

snip.....

The rate of transmission of CWD has been reported to be as high as 30% and can approach 100% among captive animals in endemic areas (Safar et al., 2008).

snip.....

In summary, in endemic areas, there is a medium probability that the soil and surrounding environment is contaminated with CWD prions and in a bioavailable form. In rural areas where CWD has not been reported and deer are present, there is a greater than negligible risk the soil is contaminated with CWD prion.

snip.....

In summary, given the volume of tourists, hunters and servicemen moving between GB and North America, the probability of at least one person travelling to/from a CWD affected area and, in doing so, contaminating their clothing, footwear and/or equipment prior to arriving in GB is greater than negligible... For deer hunters, specifically, the risk is likely to be greater given the increased contact with deer and their environment. However, there is significant uncertainty associated with these estimates.

snip.....

Therefore, it is considered that farmed and park deer may have a higher probability of exposure to CWD transferred to the environment than wild deer given the restricted habitat range and higher frequency of contact with tourists and returning GB residents.

snip.....



TUESDAY, APRIL 18, 2017 

*** EXTREME USA FDA PART 589 TSE PRION FEED LOOP HOLE STILL EXIST, AND PRICE OF POKER GOES UP ***


TUESDAY, JANUARY 17, 2017 

FDA PART 589 -- SUBSTANCES PROHIBITED FROM USE IN ANIMAL FOOD OR FEEDVIOLATIONS OFFICIAL ACTION INDICATED OAI UPDATE 2016 to 2017 BSE TSE PRION


THIS April, 4, 2017 

violation of the mad cow 21 CFR 589.2000 OAI is very serious for the great state of Michigan, some 20 years post FDA mad cow feed of August 1997. if would most likely take a FOIA request and a decade of wrangling to find out more. 

TUESDAY, JANUARY 17, 2017

FDA PART 589 -- SUBSTANCES PROHIBITED FROM USE IN ANIMAL FOOD OR FEEDVIOLATIONS OFFICIAL ACTION INDICATED OAI UPDATE 2016 to 2017 BSE TSE PRION

FDA PART 589 -- SUBSTANCES PROHIBITED FROM USE IN ANIMAL FOOD OR FEEDVIOLATIONS OFFICIAL ACTION INDICATED OAI UPDATE 2016 to 2017 BSE TSE PRION 

I would kindly like to comment on this FDA BSE/Ruminant Feed Inspections Firms Inventory (excel format)4 format, for reporting these breaches of BSE TSE prion protocols, from the extensive mad cow feed ban warning letters the fda use to put out for each violations. simply put, this excel format sucks, and the FDA et al intentionally made it this difficult to follow the usda fda mad cow follies. this is an intentional format to make it as difficult as possible to follow these breaches of the mad cow TSE prion safety feed protocols. to have absolutely no chronological or numerical order, and to format such violations in a way that they are almost impossible to find, says a lot about just how far the FDA and our fine federal friends will go through to hide these continued violations of the BSE TSE prion mad cow feed ban, and any breaches of protocols there from. once again, the wolf guarding the henhouse $$$

NAI = NO ACTION INDICATED

OAI = OFFICIAL ACTION INDICATED

VAI = VOLUNTARY ACTION INDICATED

RTS = REFERRED TO STATE

OAI (Official Action Indicated) when inspectors find significant objectionable conditions or practices and believe that regulatory sanctions are warranted to address the establishment’s lack of compliance with the regulation. An example of an OAI classification would be findings of manufacturing procedures insufficient to ensure that ruminant feed is not contaminated with prohibited material. Inspectors will promptly re-inspect facilities classified OAI after regulatory sanctions have been applied to determine whether the corrective actions are adequate to address the objectionable conditions. 

2016


ONE more thing, please remember, the label does not have to say ''deer ration'' for cervid to be pumped up with. you can get the same ''high protein'' from many sources of high protein feed for animals other than cattle, and feed them to cervid...

Saturday, August 29, 2009

FOIA REQUEST FEED RECALL 2009 Product may have contained prohibited materials Bulk Whole Barley, Recall # V-256-2009


Friday, September 4, 2009

FOIA REQUEST ON FEED RECALL PRODUCT 429,128 lbs. feed for ruminant animals may have been contaminated with prohibited material Recall # V-258-2009


WEDNESDAY, JULY 11, 2018 

CONFIDENTIAL IN CONFIDENCE SPONGIFORM ENCEPHALOPATHY OF PIGS FDA EMERGENCY REQUEST FOR RULE CHANGE USA Section 21 C.F.R. 589.2000

http://transmissiblespongiformencephalopathy.blogspot.com/2018/07/confidential-in-confidence-spongiform.html

TUESDAY, JULY 10, 2018
CONFIDENTIAL IN CONFIDENCE SPONGIFORM ENCEPHALOPATHY OF PIGS
*** ''but feeding of other ruminant protein, including scrapie-infected sheep, can continue to pigs.''
CONFIDENTIAL SPONGIFORM ENCEPHALOPATHY OF PIGS
http://madporcinedisease.blogspot.com/2018/07/confidential-in-confidence-spongiform.html


ZOONOTIC CHRONIC WASTING DISEASE CWD TSE PRION UPDATE

here is the latest;

PRION 2018 CONFERENCE
Oral transmission of CWD into Cynomolgus macaques: signs of atypical disease, prion conversion and infectivity in macaques and bio-assayed transgenic mice 
Hermann M. Schatzl, Samia Hannaoui, Yo-Ching Cheng, Sabine Gilch (Calgary Prion Research Unit, University of Calgary, Calgary, Canada) Michael Beekes (RKI Berlin), Walter Schulz-Schaeffer (University of Homburg/Saar, Germany), Christiane Stahl-Hennig (German Primate Center) & Stefanie Czub (CFIA Lethbridge). 
To date, BSE is the only example of interspecies transmission of an animal prion disease into humans. The potential zoonotic transmission of CWD is an alarming issue and was addressed by many groups using a variety of in vitro and in vivo experimental systems. Evidence from these studies indicated a substantial, if not absolute, species barrier, aligning with the absence of epidemiological evidence suggesting transmission into humans. Studies in non-human primates were not conclusive so far, with oral transmission into new-world monkeys and no transmission into old-world monkeys. 
Our consortium has challenged 18 Cynomolgus macaques with characterized CWD material, focusing on oral transmission with muscle tissue. Some macaques have orally received a total of 5 kg of muscle material over a period of 2 years. After 5-7 years of incubation time some animals showed clinical symptoms indicative of prion disease, and prion neuropathology and PrPSc deposition were detected in spinal cord and brain of some euthanized animals. PrPSc in immunoblot was weakly detected in some spinal cord materials and various tissues tested positive in RT-QuIC, including lymph node and spleen homogenates. To prove prion infectivity in the macaque tissues, we have intracerebrally inoculated 2 lines of transgenic mice, expressing either elk or human PrP. At least 3 TgElk mice, receiving tissues from 2 different macaques, showed clinical signs of a progressive prion disease and brains were positive in immunoblot and RT-QuIC. Tissues (brain, spinal cord and spleen) from these and pre-clinical mice are currently tested using various read-outs and by second passage in mice. Transgenic mice expressing human PrP were so far negative for clear clinical prion disease (some mice >300 days p.i.). In parallel, the same macaque materials are inoculated into bank voles. 
Taken together, there is strong evidence of transmissibility of CWD orally into macaques and from macaque tissues into transgenic mouse models, although with an incomplete attack rate. The clinical and pathological presentation in macaques was mostly atypical, with a strong emphasis on spinal cord pathology. Our ongoing studies will show whether the transmission of CWD into macaques and passage in transgenic mice represents a form of non-adaptive prion amplification, and whether macaque-adapted prions have the potential to infect mice expressing human PrP. The notion that CWD can be transmitted orally into both new-world and old-world non-human primates asks for a careful reevaluation of the zoonotic risk of CWD.
***> The notion that CWD can be transmitted orally into both new-world and old-world non-human primates asks for a careful reevaluation of the zoonotic risk of CWD. <***

READING OVER THE PRION 2018 ABSTRACT BOOK, LOOKS LIKE THEY FOUND THAT from this study ;
P190 Human prion disease mortality rates by occurrence of chronic wasting disease in freeranging cervids, United States 
Abrams JY (1), Maddox RA (1), Schonberger LB (1), Person MK (1), Appleby BS (2), Belay ED (1) (1) Centers for Disease Control and Prevention (CDC), National Center for Emerging and Zoonotic Infectious Diseases, Atlanta, GA, USA (2) Case Western Reserve University, National Prion Disease Pathology Surveillance Center (NPDPSC), Cleveland, OH, USA. 
SEEMS THAT THEY FOUND Highly endemic states had a higher rate of prion disease mortality compared to non-CWD states.
AND ANOTHER STUDY;
P172 Peripheral Neuropathy in Patients with Prion Disease 
Wang H(1), Cohen M(1), Appleby BS(1,2) (1) University Hospitals Cleveland Medical Center, Cleveland, Ohio (2) National Prion Disease Pathology Surveillance Center, Cleveland, Ohio..
IN THIS STUDY, THERE WERE autopsy-proven prion cases from the National Prion Disease Pathology Surveillance Center that were diagnosed between September 2016 to March 2017, AND included 104 patients.
SEEMS THEY FOUND THAT The most common sCJD subtype was MV1-2 (30%), followed by MM1-2 (20%), AND THAT The Majority of cases were male (60%), AND half of them had exposure to wild game.
snip...

see more on Prion 2017 Macaque study from Prion 2017 Conference and other updated science on cwd tse prion zoonosis below...terry

just out CDC...see;

Research
Susceptibility of Human Prion Protein to Conversion by Chronic Wasting Disease Prions
Marcelo A. BarriaComments to Author , Adriana Libori, Gordon Mitchell, and Mark W. Head Author affiliations: National CJD Research and Surveillance Unit, University of Edinburgh, Edinburgh, Scotland, UK (M.A. Barria, A. Libori, M.W. Head); National and OIE Reference Laboratory for Scrapie and CWD, Canadian Food Inspection Agency, Ottawa, Ontario, Canada (G. Mitchell)
M. A. Barria et al.
ABSTRACT
Chronic wasting disease (CWD) is a contagious and fatal neurodegenerative disease and a serious animal health issue for deer and elk in North America. The identification of the first cases of CWD among free-ranging reindeer and moose in Europe brings back into focus the unresolved issue of whether CWD can be zoonotic like bovine spongiform encephalopathy. We used a cell-free seeded protein misfolding assay to determine whether CWD prions from elk, white-tailed deer, and reindeer in North America can convert the human prion protein to the disease-associated form. We found that prions can convert, but the efficiency of conversion is affected by polymorphic variation in the cervid and human prion protein genes. In view of the similarity of reindeer, elk, and white-tailed deer in North America to reindeer, red deer, and roe deer, respectively, in Europe, a more comprehensive and thorough assessment of the zoonotic potential of CWD might be warranted. 

Molecular Barriers to Zoonotic Transmission of Prions 
Marcelo A. Barria, Aru Balachandran, Masanori Morita, Tetsuyuki Kitamoto, Rona Barron, Jean Manson, Richard Knight, James W. Ironside, and Mark W. Headcorresponding author 
snip... 
The conversion of human PrPC by CWD brain homogenate in PMCA reactions was less efficient when the amino acid at position 129 was valine rather than methionine. 
***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. 

snip... 

However, we can say with confidence that under the conditions used here, none of the animal isolates tested were as efficient as C-type BSE in converting human PrPC, which is reassuring. 
***Less reassuring is the finding that there is no absolute barrier to the conversion of human PrPC by CWD prions in a protocol using a single round of PMCA and an entirely human substrate prepared from the target organ of prion diseases, the brain. 

 Prion 2017 
Conference Abstracts CWD 2017 PRION CONFERENCE 
First evidence of intracranial and peroral transmission of Chronic Wasting Disease (CWD) into Cynomolgus macaques: a work in progress 
Stefanie Czub1, Walter Schulz-Schaeffer2, Christiane Stahl-Hennig3, Michael Beekes4, Hermann Schaetzl5 and Dirk Motzkus6 1 
University of Calgary Faculty of Veterinary Medicine/Canadian Food Inspection Agency; 2Universitatsklinikum des Saarlandes und Medizinische Fakultat der Universitat des Saarlandes; 3 Deutsches Primaten Zentrum/Goettingen; 4 Robert-Koch-Institut Berlin; 5 University of Calgary Faculty of Veterinary Medicine; 6 presently: Boehringer Ingelheim Veterinary Research Center; previously: Deutsches Primaten Zentrum/Goettingen 
This is a progress report of a project which started in 2009. 21 cynomolgus macaques were challenged with characterized CWD material from white-tailed deer (WTD) or elk by intracerebral (ic), oral, and skin exposure routes. Additional blood transfusion experiments are supposed to assess the CWD contamination risk of human blood product. Challenge materials originated from symptomatic cervids for ic, skin scarification and partially per oral routes (WTD brain). Challenge material for feeding of muscle derived from preclinical WTD and from preclinical macaques for blood transfusion experiments. We have confirmed that the CWD challenge material contained at least two different CWD agents (brain material) as well as CWD prions in muscle-associated nerves. Here we present first data on a group of animals either challenged ic with steel wires or per orally and sacrificed with incubation times ranging from 4.5 to 6.9 years at postmortem. Three animals displayed signs of mild clinical disease, including anxiety, apathy, ataxia and/or tremor. In four animals wasting was observed, two of those had confirmed diabetes. All animals have variable signs of prion neuropathology in spinal cords and brains and by supersensitive IHC, reaction was detected in spinal cord segments of all animals. Protein misfolding cyclic amplification (PMCA), real-time quaking-induced conversion (RT-QuiC) and PET-blot assays to further substantiate these findings are on the way, as well as bioassays in bank voles and transgenic mice. At present, a total of 10 animals are sacrificed and read-outs are ongoing. Preclinical incubation of the remaining macaques covers a range from 6.4 to 7.10 years. Based on the species barrier and an incubation time of > 5 years for BSE in macaques and about 10 years for scrapie in macaques, we expected an onset of clinical disease beyond 6 years post inoculation. 
PRION 2017 
DECIPHERING NEURODEGENERATIVE DISORDERS 
Subject: PRION 2017 CONFERENCE DECIPHERING NEURODEGENERATIVE DISORDERS VIDEO 
PRION 2017 
CONFERENCE DECIPHERING NEURODEGENERATIVE DISORDERS 
*** PRION 2017 CONFERENCE VIDEO 
https://www.cste2.org/Webinars/files/CWD_Slides_FINAL.pdf

Cervid to human prion transmission 

Kong, Qingzhong 

Case Western Reserve University, Cleveland, OH, United States

Abstract 

Prion disease is transmissible and invariably fatal. Chronic wasting disease (CWD) is the prion disease affecting deer, elk and moose, and it is a widespread and expanding epidemic affecting 22 US States and 2 Canadian provinces so far. CWD poses the most serious zoonotic prion transmission risks in North America because of huge venison consumption (>6 million deer/elk hunted and consumed annually in the USA alone), significant prion infectivity in muscles and other tissues/fluids from CWD-affected cervids, and usually high levels of individual exposure to CWD resulting from consumption of the affected animal among often just family and friends. However, we still do not know whether CWD prions can infect humans in the brain or peripheral tissues or whether clinical/asymptomatic CWD zoonosis has already occurred, and we have no essays to reliably detect CWD infection in humans. 

We hypothesize that: 

(1) The classic CWD prion strain can infect humans at low levels in the brain and peripheral lymphoid tissues; 

(2) The cervid-to-human transmission barrier is dependent on the cervid prion strain and influenced by the host (human) prion protein (PrP) primary sequence; 

(3) Reliable essays can be established to detect CWD infection in humans; and 

(4) CWD transmission to humans has already occurred. We will test these hypotheses in 4 Aims using transgenic (Tg) mouse models and complementary in vitro approaches. 

Aim 1 will prove that the classical CWD strain may infect humans in brain or peripheral lymphoid tissues at low levels by conducting systemic bioassays in a set of humanized Tg mouse lines expressing common human PrP variants using a number of CWD isolates at varying doses and routes. Experimental human CWD samples will also be generated for Aim 3. 

Aim 2 will test the hypothesis that the cervid-to-human prion transmission barrier is dependent on prion strain and influenced by the host (human) PrP sequence by examining and comparing the transmission efficiency and phenotypes of several atypical/unusual CWD isolates/strains as well as a few prion strains from other species that have adapted to cervid PrP sequence, utilizing the same panel of humanized Tg mouse lines as in Aim 1. 

Aim 3 will establish reliable essays for detection and surveillance of CWD infection in humans by examining in details the clinical, pathological, biochemical and in vitro seeding properties of existing and future experimental human CWD samples generated from Aims 1-2 and compare them with those of common sporadic human Creutzfeldt-Jakob disease (sCJD) prions. 

Aim 4 will attempt to detect clinical CWD-affected human cases by examining a significant number of brain samples from prion-affected human subjects in the USA and Canada who have consumed venison from CWD-endemic areas utilizing the criteria and essays established in Aim 3. The findings from this proposal will greatly advance our understandings on the potential and characteristics of cervid prion transmission in humans, establish reliable essays for CWD zoonosis and potentially discover the first case(s) of CWD infection in humans.

Public Health Relevance

There are significant and increasing human exposure to cervid prions because chronic wasting disease (CWD, a widespread and highly infectious prion disease among deer and elk in North America) continues spreading and consumption of venison remains popular, but our understanding on cervid-to-human prion transmission is still very limited, raising public health concerns. This proposal aims to define the zoonotic risks of cervid prions and set up and apply essays to detect CWD zoonosis using mouse models and in vitro methods. The findings will greatly expand our knowledge on the potentials and characteristics of cervid prion transmission in humans, establish reliable essays for such infections and may discover the first case(s) of CWD infection in humans.

 Funding Agency

Agency

National Institute of Health (NIH)

Institute

National Institute of Neurological Disorders and Stroke (NINDS)

Type

Research Project (R01)

Project #

5R01NS088604-04

Application #

9517118

Study Section

Cellular and Molecular Biology of Neurodegeneration Study Section (CMND)

Program Officer Wong, May

Project Start 2015-09-30 Project End 2019-07-31 Budget Start 2018-08-01 Budget End 2019-07-31 Support Year 4 Fiscal Year 2018 Total Cost Indirect Cost Institution Name Case Western Reserve University Department Pathology Type Schools of Medicine DUNS # 077758407 City Cleveland State OH Country United States Zip Code 44106

 Related projects

NIH 2018 R01 NS Cervid to human prion transmission Kong, Qingzhong / Case Western Reserve University 

NIH 2017 R01 NS Cervid to human prion transmission Kong, Qingzhong / Case Western Reserve University 

NIH 2016 R01 NS Cervid to human prion transmission Kong, Qingzhong / Case Western Reserve University 

NIH 2015 R01 NS Cervid to human prion transmission Kong, Qingzhong / Case Western Reserve University $337,507



ZOONOTIC, ZOONOSIS, CHRONIC WASTING DISEASE CWD TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHY TSE PRION 

10. ZOONOTIC, ZOONOSIS, CHRONIC WASTING DISEASE CWD TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHY TSE PRION AKA MAD DEER ELK DISEASE IN HUMANS, has it already happened, that should be the question... 

''In particular the US data do not clearly exclude the possibility of human (sporadic or familial) TSE development due to consumption of venison. The Working Group thus recognizes a potential risk to consumers if a TSE would be present in European cervids.'' Scientific opinion on chronic wasting disease (II)

EFSA Panel on Biological Hazards (BIOHAZ) Antonia Ricci Ana Allende Declan Bolton Marianne Chemaly Robert Davies Pablo Salvador Fernández Escámez ... See all authors 

First published: 17 January 2018 https://doi.org/10.2903/j.efsa.2018.5132 ;

also, see; 

8. Even though human TSE‐exposure risk through consumption of game from European cervids can be assumed to be minor, if at all existing, no final conclusion can be drawn due to the overall lack of scientific data. In particular the US data do not clearly exclude the possibility of human (sporadic or familial) TSE development due to consumption of venison. The Working Group thus recognizes a potential risk to consumers if a TSE would be present in European cervids. It might be prudent considering appropriate measures to reduce such a risk, e.g. excluding tissues such as CNS and lymphoid tissues from the human food chain, which would greatly reduce any potential risk for consumers. However, it is stressed that currently, no data regarding a risk of TSE infections from cervid products are available. 

snip... 

The tissue distribution of infectivity in CWD‐infected cervids is now known to extend beyond CNS and lymphoid tissues. While the removal of these specific tissues from the food chain would reduce human dietary exposure to infectivity, exclusion from the food chain of the whole carcass of any infected animal would be required to eliminate human dietary exposure. 
https://efsa.onlinelibrary..wiley.com/doi/full/10.2903/j.efsa.2018.5132

zoonosis zoonotic cervid tse prion cwd to humans, preparing for the storm 

***An alternative to modeling the species barrier is the cell-free conversion assay which points to CWD as the animal prion disease with the greatest zoonotic potential, after (and very much less than) BSE.116*** https://www.tandfonline.com/doi/pdf/10.4161/pri.29237
 
To date there is no direct evidence that CWD has been or can be transmitted from animals to humans. 

However, initial findings from a laboratory research project funded by the Alberta Prion Research Institute (APRI) and Alberta Livestock Meat Agency (ALMA), and led by a Canadian Food Inspection Agency (CFIA) scientist indicate that CWD has been transmitted to cynomolgus macaques (the non-human primate species most closely related to humans that may be used in research), through both the intracranial and oral routes of exposure. 

Both infected brain and muscle tissues were found to transmit disease. 

Health Canada’s Health Products and Food Branch (HPFB) was asked to consider the impact of these findings on the Branch’s current position on CWD in health products and foods. 

Summary and Recommendation: 

snip...

Health Portfolio partners were recently made aware of initial findings from a research project led by a CFIA scientist that have demonstrated that cynomolgus macaques can be infected via intracranial exposure and oral gavage with CWD infected muscle. 

These findings suggest that CWD, under specific experimental conditions, has the potential to cross the human species barrier, including by enteral feeding of CWD infected muscle. https://www.thetyee.ca/Documents/2017/06/24/Risk-Advisory-Opinion-CWD-2017.pdf

*** WDA 2016 NEW YORK *** 

We found that CWD adapts to a new host more readily than BSE and that human PrP was unexpectedly prone to misfolding by CWD prions. 

In addition, we investigated the role of specific regions of the bovine, deer and human PrP protein in resistance to conversion by prions from another species. 

***We have concluded that the human protein has a region that confers unusual susceptibility to conversion by CWD prions. 

Student Presentations Session 2 

The species barriers and public health threat of CWD and BSE prions 

Ms. Kristen Davenport1, Dr. Davin Henderson1, Dr. Candace Mathiason1, Dr. Edward Hoover1 1Colorado State University 

Chronic wasting disease (CWD) is spreading rapidly through cervid populations in the USA. Bovine spongiform encephalopathy (BSE, mad cow disease) arose in the 1980s because cattle were fed recycled animal protein. 

These and other prion diseases are caused by abnormal folding of the normal prion protein (PrP) into a disease causing form (PrPd), which is pathogenic to nervous system cells and can cause subsequent PrP to misfold. CWD spreads among cervids very efficiently, but it has not yet infected humans. On the other hand, BSE was spread only when cattle consumed infected bovine or ovine tissue, but did infect humans and other species. 

The objective of this research is to understand the role of PrP structure in cross-species infection by CWD and BSE. To study the propensity of each species’ PrP to be induced to misfold by the presence of PrPd from verious species, we have used an in vitro system that permits detection of PrPd in real-time. 

We measured the conversion efficiency of various combinations of PrPd seeds and PrP substrate combinations. 

We observed the cross-species behavior of CWD and BSE, in addition to feline-adapted CWD and BSE. We found that CWD adapts to a new host more readily than BSE and that human PrP was unexpectedly prone to misfolding by CWD prions. In addition, we investigated the role of specific regions of the bovine, deer and human PrP protein in resistance to conversion by prions from another species. 

***We have concluded that the human protein has a region that confers unusual susceptibility to conversion by CWD prions. CWD is unique among prion diseases in its rapid spread in natural populations. BSE prions are essentially unaltered upon passage to a new species, while CWD adapts to the new species. This adaptation has consequences for surveillance of humans exposed to CWD. Wildlife Disease Risk Communication Research Contributes to Wildlife Trust Administration Exploring perceptions about chronic wasting disease risks among wildlife and agriculture professionals and stakeholdershttp://www.wda2016.org/uploads/5/8/6/1/58613359/wda_2016_conference_proceedings_low_res.pdf
CDC CWD 2018 TRANSMISSION

https://www.cdc.gov/prions/cwd/transmission.html

TUESDAY, SEPTEMBER 12, 2017 

CDC Now Recommends Strongly consider having the deer or elk tested for CWD before you eat the meat http://chronic-wasting-disease.blogspot.com/2017/09/cdc-now-recommends-strongly-consider.html

SATURDAY, JANUARY 27, 2018 

CDC CHRONIC WASTING DISEASE CWD TSE PRION UPDATE REPORT USA JANUARY 2018http://chronic-wasting-disease.blogspot.com/2018/01/cdc-chronic-wasting-disease-cwd-tse.html

Subject: CDC CHRONIC WASTING DISEASE CWD TSE PRION UPDATE REPORT USA JANUARY 2018

CHRONIC WASTING DISEASE CWD TSE PRION IS THE USA AND NORTH AMERICA'S MAD COW DISEASE. 

THE USDA INC ET AL WORKED VERY HARD CONCEALING BSE TSE PRION IN CATTLE. they almost succeeded $$$

BUT CWD TSE PRION IN CERVIDS IS A DIFFERENT BEAST, THE COVER UP THERE, USDA INC COULD NOT CONTAIN.

SPORADIC CJD IS 85%+ OF ALL HUMAN TSE PRION DISEASE.

SPORADIC CJD HAS NOW BEEN LINKED TO TYPICAL AND ATYPICAL BSE, SCRAPIE, AND CWD.

SPORADIC/SPONTANEOUS TSE HAS NEVER BEEN PROVEN.

***Moreover, sporadic disease has never been observed in breeding colonies or primate research laboratories, most notably among hundreds of animals over several decades of study at the National Institutes of Health25, and in nearly twenty older animals continuously housed in our own facility.***https://www.nature.com/articles/srep11573 


CDC CWD TSE PRION UPDATE USA JANUARY 2018

As of January 2018, CWD in free-ranging deer, elk and/or moose has been reported in at least 22 states in the continental United States, as well as two provinces in Canada. In addition, CWD has been reported in reindeer and moose in Norway, and a small number of imported cases have been reported in South Korea. The disease has also been found in farmed deer and elk. CWD was first identified in captive deer in the late 1960s in Colorado and in wild deer in 1981. By the 1990s, it had been reported in surrounding areas in northern Colorado and southern Wyoming. Since 2000, the area known to be affected by CWD in free-ranging animals has increased to at least 22 states, including states in the Midwest, Southwest, and limited areas on the East Coast.. It is possible that CWD may also occur in other states without strong animal surveillance systems, but that cases haven’t been detected yet. Once CWD is established in an area, the risk can remain for a long time in the environment. The affected areas are likely to continue to expand. Nationwide, the overall occurrence of CWD in free-ranging deer and elk is relatively low. However, in several locations where the disease is established, infection rates may exceed 10 percent (1 in 10), and localized infection rates of more than 25 percent (1 in 4) have been reported. The infection rates among some captive deer can be much higher, with a rate of 79% (nearly 4 in 5) reported from at least one captive herd. As of January 2018, there were 186 counties in 22 states with reported CWD in free-ranging cervids... 

Chronic Wasting Disease Among Free-Ranging Cervids by County, United States, January 2018 

snip.... https://www.cdc.gov/prions/cwd/occurrence.html

*** 2017-2018 CWD TSE Prion UPDATE

https://www.cdc.gov/prions/cwd/occurrence.html

*** The potential impact of prion diseases on human health was greatly magnified by the recognition that interspecies transfer of BSE to humans by beef ingestion resulted in vCJD. While changes in animal feed constituents and slaughter practices appear to have curtailed vCJD, there is concern that CWD of free-ranging deer and elk in the U.S. might also cross the species barrier. Thus, consuming venison could be a source of human prion disease. Whether BSE and CWD represent interspecies scrapie transfer or are newly arisen prion diseases is unknown. Therefore, the possibility of transmission of prion disease through other food animals cannot be ruled out. There is evidence that vCJD can be transmitted through blood transfusion. There is likely a pool of unknown size of asymptomatic individuals infected with vCJD, and there may be asymptomatic individuals infected with the CWD equivalent. These circumstances represent a potential threat to blood, blood products, and plasma supplies. 

http://cdmrp.army.mil/prevfunded/nprp/NPRP_Summit_Final_Report.pdf

Transmission Studies

Mule deer transmissions of CWD were by intracerebral inoculation and compared with natural cases {the following was written but with a single line marked through it ''first passage (by this route)}....TSS

resulted in a more rapidly progressive clinical disease with repeated episodes of synocopy ending in coma. One control animal became affected, it is believed through contamination of inoculum (?saline). Further CWD transmissions were carried out by Dick Marsh into ferret, mink and squirrel monkey. Transmission occurred in ALL of these species with the shortest incubation period in the ferret.

snip...https://web.archive.org/web/20090506002237/http://www.bseinquiry.gov.uk/files/mb/m11b/tab01.pdf
http://www.fsis.usda.gov/OPPDE/Comments/03-025IFA/03-025IFA-2.pdf

Prion Infectivity in Fat of Deer with Chronic Wasting Disease▿ 

Brent Race#, Kimberly Meade-White#, Richard Race and Bruce Chesebro* + Author Affiliations

In mice, prion infectivity was recently detected in fat. Since ruminant fat is consumed by humans and fed to animals, we determined infectivity titers in fat from two CWD-infected deer. Deer fat devoid of muscle contained low levels of CWD infectivity and might be a risk factor for prion infection of other species.http://jvi.asm.org/content/83/18/9608.full

Prions in Skeletal Muscles of Deer with Chronic Wasting Disease 

Here bioassays in transgenic mice expressing cervid prion protein revealed the presence of infectious prions in skeletal muscles of CWD-infected deer, demonstrating that humans consuming or handling meat from CWD-infected deer are at risk to prion exposure.http://science.sciencemag.org/content/311/5764/1117.long

*** now, let’s see what the authors said about this casual link, personal communications years ago, and then the latest on the zoonotic potential from CWD to humans from the TOKYO PRION 2016 CONFERENCE.

see where it is stated NO STRONG evidence. so, does this mean there IS casual evidence ???? “Our conclusion stating that we found no strong evidence of CWD transmission to humans”

From: TSS (216-119-163-189.ipset45.wt.net)

Subject: CWD aka MAD DEER/ELK TO HUMANS ???

Date: September 30, 2002 at 7:06 am PST

From: "Belay, Ermias"

To: Cc: "Race, Richard (NIH)" ; ; "Belay, Ermias"

Sent: Monday, September 30, 2002 9:22 AM

Subject: RE: TO CDC AND NIH - PUB MED- 3 MORE DEATHS - CWD - YOUNG HUNTERS

Dear Sir/Madam,

In the Archives of Neurology you quoted (the abstract of which was attached to your email), we did not say CWD in humans will present like variant CJD.. That assumption would be wrong. I encourage you to read the whole article and call me if you have questions or need more clarification (phone: 404-639-3091). Also, we do not claim that "no-one has ever been infected with prion disease from eating venison." Our conclusion stating that we found no strong evidence of CWD transmission to humans in the article you quoted or in any other forum is limited to the patients we investigated.

Ermias Belay, M.D. Centers for Disease Control and Prevention

-----Original Message-----

From: Sent: Sunday, September 29, 2002 10:15 AM

To: rr26k@nih.gov; rrace@niaid.nih.gov; ebb8@CDC.GOV

Subject: TO CDC AND NIH - PUB MED- 3 MORE DEATHS - CWD - YOUNG HUNTERS

Sunday, November 10, 2002 6:26 PM ......snip........end..............TSS

Thursday, April 03, 2008

A prion disease of cervids: Chronic wasting disease 2008 1: Vet Res. 2008 Apr 3;39(4):41 A prion disease of cervids: Chronic wasting disease Sigurdson CJ.

snip...

*** twenty-seven CJD patients who regularly consumed venison were reported to the Surveillance Center***,

snip... full text ;http://chronic-wasting-disease.blogspot.com/2008/04/prion-disease-of-cervids-chronic.html

> However, to date, no CWD infections have been reported in people. 

key word here is 'reported'. science has shown that CWD in humans will look like sporadic CJD. SO, how can one assume that CWD has not already transmitted to humans? they can't, and it's as simple as that. from all recorded science to date, CWD has already transmitted to humans, and it's being misdiagnosed as sporadic CJD. ...terry 

*** LOOKING FOR CWD IN HUMANS AS nvCJD or as an ATYPICAL CJD, LOOKING IN ALL THE WRONG PLACES $$$ ***

*** These results would seem to suggest that CWD does indeed have zoonotic potential, at least as judged by the compatibility of CWD prions and their human PrPC target. Furthermore, extrapolation from this simple in vitro assay suggests that if zoonotic CWD occurred, it would most likely effect those of the PRNP codon 129-MM genotype and that the PrPres type would be similar to that found in the most common subtype of sCJD (MM1).*** http://www.tandfonline.com/doi/full/10.4161/pri.28124?src=recsys
http://www.tandfonline.com/doi/pdf/10.4161/pri.28124?needAccess=true
https://wwwnc.cdc.gov/eid/article/20/1/13-0858_article


SEE; Travel History, Hunting, and Venison Consumption Related to Prion Disease Exposure, 2006-2007 FoodNet Population Survey

Monday, May 23, 2011

CDC Assesses Potential Human Exposure to Prion Diseases Travel Warning

Public release date: 23-May-2011

Contact: Francesca Costanzo adajmedia@elsevier.com 215-239-3249 Elsevier Health Sciences

CDC assesses potential human exposure to prion diseases Study results reported in the Journal of the American Dietetic Association Philadelphia, PA, May 23, 2011 – Researchers from the Centers for Disease Control and Prevention (CDC) have examined the potential for human exposure to prion diseases, looking at hunting, venison consumption, and travel to areas in which prion diseases have been reported in animals. Three prion diseases in particular – bovine spongiform encephalopathy (BSE or “Mad Cow Disease”), variant Creutzfeldt-Jakob disease (vCJD), and chronic wasting disease (CWD) – were specified in the investigation. The results of this investigation are published in the June issue of the Journal of the American Dietetic Association.

“While prion diseases are rare, they are generally fatal for anyone who becomes infected. More than anything else, the results of this study support the need for continued surveillance of prion diseases,” commented lead investigator Joseph Y. Abrams, MPH, National Center for Emerging and Zoonotic Infectious Diseases, CDC, Atlanta.”But it’s also important that people know the facts about these diseases, especially since this study shows that a good number of people have participated in activities that may expose them to infection-causing agents.”

Although rare, human prion diseases such as CJD may be related to BSE. Prion (proteinaceous infectious particles) diseases are a group of rare brain diseases that affect humans and animals. When a person gets a prion disease, brain function is impaired. This causes memory and personality changes, dementia, and problems with movement. All of these worsen over time. These diseases are invariably fatal. Since these diseases may take years to manifest, knowing the extent of human exposure to possible prion diseases could become important in the event of an outbreak.

CDC investigators evaluated the results of the 2006-2007 population survey conducted by the Foodborne Diseases Active Surveillance Network (FoodNet). This survey collects information on food consumption practices, health outcomes, and demographic characteristics of residents of the participating Emerging Infections Program sites. The survey was conducted in Connecticut, Georgia, Maryland, Minnesota, New Mexico, Oregon, and Tennessee, as well as five counties in the San Francisco Bay area, seven counties in the Greater Denver area, and 34 counties in western and northeastern New York.

Survey participants were asked about behaviors that could be associated with exposure to the agents causing BSE and CWD, including travel to the nine countries considered to be BSE-endemic (United Kingdom, Republic of Ireland, France, Portugal, Switzerland, Italy, the Netherlands, Germany, Spain) and the cumulative length of stay in each of those countries. Respondents were asked if they ever had hunted for deer or elk, and if that hunting had taken place in areas considered to be CWD-endemic (northeastern Colorado, southeastern Wyoming or southwestern Nebraska). They were also asked if they had ever consumed venison, the frequency of consumption, and whether the meat came from the wild.

The proportion of survey respondents who reported travel to at least one of the nine BSE endemic countries since 1980 was 29.5%. Travel to the United Kingdom was reported by 19.4% of respondents, higher than to any other BSE-endemic country. Among those who traveled, the median duration of travel to the United Kingdom (14 days) was longer than that of any other BSE-endemic country. Travelers to the UK were more likely to have spent at least 30 days in the country (24.9%) compared to travelers to any other BSE endemic country. The prevalence and extent of travel to the UK indicate that health concerns in the UK may also become issues for US residents.

The proportion of survey respondents reporting having hunted for deer or elk was 18.5% and 1.2% reported having hunted for deer or elk in CWD-endemic areas. Venison consumption was reported by 67.4% of FoodNet respondents, and 88.6% of those reporting venison consumption had obtained all of their meat from the wild. These findings reinforce the importance of CWD surveillance and control programs for wild deer and elk to reduce human exposure to the CWD agent. Hunters in CWD-endemic areas are advised to take simple precautions such as: avoiding consuming meat from sickly deer or elk, avoiding consuming brain or spinal cord tissues, minimizing the handling of brain and spinal cord tissues, and wearing gloves when field-dressing carcasses.

According to Abrams, “The 2006-2007 FoodNet population survey provides useful information should foodborne prion infection become an increasing public health concern in the future. The data presented describe the prevalence of important behaviors and their associations with demographic characteristics. Surveillance of BSE, CWD, and human prion diseases are critical aspects of addressing the burden of these diseases in animal populations and how that may relate to human health.”

###

The article is “Travel history, hunting, and venison consumption related to prion disease exposure, 2006-2007 FoodNet population survey” by Joseph Y. Abrams, MPH; Ryan A. Maddox, MPH; Alexis R Harvey, MPH; Lawrence B. Schonberger, MD; and Ermias D. Belay, MD. It appears in the Journal of the American Dietetic Association, Volume 111, Issue 6 (June 2011) published by Elsevier.

In an accompanying podcast CDC’s Joseph Y. Abrams discusses travel, hunting, and eating venison in relation to prion diseases. It is available at http://adajournal.org/content/podcast.
http://www.eurekalert.org/pub_releases/2011-05/ehs-cap051811.php

Thursday, May 26, 2011

Travel History, Hunting, and Venison Consumption Related to Prion Disease Exposure, 2006-2007 FoodNet Population Survey

Journal of the American Dietetic Association Volume 111, Issue 6 , Pages 858-863, June 2011.

Travel History, Hunting, and Venison Consumption Related to Prion Disease Exposure, 2006-2007 FoodNet Population Survey

Joseph Y. Abrams, MPH, Ryan A. Maddox, MPH , Alexis R. Harvey, MPH , Lawrence B. Schonberger, MD , Ermias D. Belay, MD

Accepted 15 November 2010. Abstract Full Text PDF References .

Abstract

The transmission of bovine spongiform encephalopathy (BSE) to human beings and the spread of chronic wasting disease (CWD) among cervids have prompted concerns about zoonotic transmission of prion diseases. Travel to the United Kingdom and other European countries, hunting for deer or elk, and venison consumption could result in the exposure of US residents to the agents that cause BSE and CWD. The Foodborne Diseases Active Surveillance Network 2006-2007 population survey was used to assess the prevalence of these behaviors among residents of 10 catchment areas across the United States. Of 17,372 survey respondents, 19.4% reported travel to the United Kingdom since 1980, and 29.5% reported travel to any of the nine European countries considered to be BSE-endemic since 1980. The proportion of respondents who had ever hunted deer or elk was 18.5%, and 1.2% had hunted deer or elk in a CWD–endemic area. More than two thirds (67.4%) reported having ever eaten deer or elk meat. Respondents who traveled spent more time in the United Kingdom (median 14 days) than in any other BSE-endemic country. Of the 11,635 respondents who had consumed venison, 59.8% ate venison at most one to two times during their year of highest consumption, and 88.6% had obtained all of their meat from the wild. The survey results were useful in determining the prevalence and frequency of behaviors that could be important factors for foodborne prion transmission.http://www.adajournal.org/article/S0002-8223(11)00278-1/abstract

PLUS, THE CDC DID NOT PUT THIS WARNING OUT FOR THE WELL BEING OF THE DEER AND ELK ; 

Thursday, May 26, 2011

Travel History, Hunting, and Venison Consumption Related to Prion Disease Exposure, 2006-2007 FoodNet Population Survey

Journal of the American Dietetic Association Volume 111, Issue 6 , Pages 858-863, June 2011.http://transmissiblespongiformencephalopathy.blogspot.com/2011/05/travel-history-hunting-and-venison.html

NOR IS THE FDA recalling this CWD positive elk meat for the well being of the dead elk ;

Wednesday, March 18, 2009

Noah's Ark Holding, LLC, Dawson, MN RECALL Elk products contain meat derived from an elk confirmed to have CWD NV, CA, TX, CO, NY, UT, FL, OK RECALLS AND FIELD CORRECTIONS: FOODS CLASS IIhttp://chronic-wasting-disease.blogspot.com/2009/03/noahs-ark-holding-llc-dawson-mn-recall.html

Transmissible Spongiform Encephalopathies

Spongiform Encephalopathy in Captive Wild ZOO BSE INQUIRYhttps://web.archive.org/web/20090506001201/http://www.bseinquiry.gov.uk/files/mb/m09a/tab03.pdf

BSE INQUIRY

CJD9/10022

October 1994

Mr R.N. Elmhirst Chairman British Deer Farmers Association Holly Lodge Spencers Lane 

BerksWell Coventry CV7 7BZ

Dear Mr Elmhirst,

CREUTZFELDT-JAKOB DISEASE (CJD) SURVEILLANCE UNIT REPORT

Thank you for your recent letter concerning the publication of the third annual report from the CJD Surveillance Unit. I am sorry that you are dissatisfied with the way in which this report was published.

The Surveillance Unit is a completely independant outside body and the Department of Health is committed to publishing their reports as soon as they become available. In the circumstances it is not the practice to circulate the report for comment since the findings of the report would not be amended.. In future we can ensure that the British Deer Farmers Association receives a copy of the report in advance of publication.

The Chief Medical Officer has undertaken to keep the public fully informed of the results of any research in respect of CJD. This report was entirely the work of the unit and was produced completely independantly of the the Department.

The statistical results reqarding the consumption of venison was put into perspective in the body of the report and was not mentioned at all in the press release. Media attention regarding this report was low key but gave a realistic presentation of the statistical findings of the Unit. This approach to publication was successful in that consumption of venison was highlighted only once by the media ie. in the News at one television proqramme.

I believe that a further statement about the report, or indeed statistical links between CJD and consumption of venison, would increase, and quite possibly give damaging credence, to the whole issue. From the low key media reports of which I am aware it seems unlikely that venison consumption will suffer adversely, if at all.http://web.archive.org/web/20030511010117/http://www.bseinquiry.gov.uk/files/yb/1994/10/00003001.pdf

*** The association between venison eating and risk of CJD shows similar pattern, with regular venison eating associated with a 9 FOLD INCREASE IN RISK OF CJD (p = 0.04). ***

*** The association between venison eating and risk of CJD shows similar pattern, with regular venison eating associated with a 9 FOLD INCREASE IN RISK OF CJD (p = 0.04). ***

*** The association between venison eating and risk of CJD shows similar pattern, with regular venison eating associated with a 9 FOLD INCREASE IN RISK OF CJD (p = 0.04). ***

There is some evidence that risk of CJD INCREASES WITH INCREASING FREQUENCY OF LAMB EATING (p = 0.02).

The evidence for such an association between beef eating and CJD is weaker (p = 0.14). When only controls for whom a relative was interviewed are included, this evidence becomes a little STRONGER (p = 0.08).

snip...

It was found that when veal was included in the model with another exposure, the association between veal and CJD remained statistically significant (p = < 0.05 for all exposures), while the other exposures ceased to be statistically significant (p = > 0.05).

snip...

In conclusion, an analysis of dietary histories revealed statistical associations between various meats/animal products and INCREASED RISK OF CJD. When some account was taken of possible confounding, the association between VEAL EATING AND RISK OF CJD EMERGED AS THE STRONGEST OF THESE ASSOCIATIONS STATISTICALLY. ...

snip...

In the study in the USA, a range of foodstuffs were associated with an increased risk of CJD, including liver consumption which was associated with an apparent SIX-FOLD INCREASE IN THE RISK OF CJD. By comparing the data from 3 studies in relation to this particular dietary factor, the risk of liver consumption became non-significant with an odds ratio of 1.2 (PERSONAL COMMUNICATION, PROFESSOR A. HOFMAN. ERASMUS UNIVERSITY, ROTTERDAM). (???...TSS)

snip...see full report ;

https://web.archive.org/web/20170126073306/http://collections..europarchive..org/tna/20090505194948/http://bseinquiry.gov.uk/files/yb/1994/08/00004001.pdf

WITH the recent findings that Scrapie will transmit to Macaque by or route, that Scrapie and CWD TSE Prion will transit to pigs orally, recent outbreak documented of TSE Prion Disease in Dromedary Camels, Algeria, atypical TSE Prion still being documented, and again just recently in the USA, of another atypical BSE case, and this discovery was only documented by testing 20k head of cattle from some 100M head of cattle in any given year in the USA, the continued denial that atypical BSE and atypical Scrapie are a transmissible disease (science has shown otherwise) this is concerning to me. Science and scientific policy makers have forgotten what Gibbs, Gajdusek, Hadlow, Alper, Zigas, even Gordon with the infamous Scrapie vaccine blunder, a discovery of valuable importance, and so many others i am failing to remember now, what some found long ago, like Dr. Gibbs, he tried to warn us about scrapie zoonosis potential, yet that went ignored for decades and decades. we/scientist/officials/the world, knows the USA FDA PART 589 TSE PRION FEED ban has failed terribly, the BSE testing has failed terribly, and the surveillance there from has failed, SRM removal breaches, all proven by the OIG or the GAO, and others. But yet, we find ourselves now debating the issue of these same risk factors for scrapie, the same risk factors that we all knew were there, with science staring us in the face, we still deny scientific facts all in the name of corporate interest. let's not continue to make these same mistakes. human and animal life is at stake here. we must remove corporate/government/lobbyist interest from the scientific policy making and regulations there from for the TSE Prion, all of them. ...Terry S. Singeltary SR.

O3 Experimental studies on prion transmission barrier and TSE pathogenesis in large animals 

Rosa Bolea(1), Acín C(1)Marín B(1), Hedman C(1), Raksa H(1), Barrio T(1), Otero A(1), LópezPérez O(1), Monleón E(1),Martín-Burriel(1), Monzón M(1), Garza MC(1), Filali H(1),Pitarch JL(1), Garcés M(1), Betancor M(1), GuijarroIM(1), GarcíaM(1), Moreno B(1),Vargas A(1), Vidal E(2), Pumarola M(2), Castilla J(3), Andréoletti O(4), Espinosa JC(5), Torres JM(5), Badiola JJ(1). 

1Centro de Investigación en Encefalopatías y Enfermedades Transmisibles Emergentes, VeterinaryFaculty, Universidad de Zaragoza; Zaragoza,Spain.2 RTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA-UAB) 3 4 INRA, ÉcoleVétérinaire, Toulouse, France.5CIC bioGUNE, Prion researchlab, Derio, Spain CISA- INIA, Valdeolmos, Madrid 28130, Spain. 

Experimental transmission of Transmissible Spongiform Encephalopathies (TSE) has been understood and related with several factors that could modify the natural development of these diseases. In fact, the behaviour of the natural disease does not match exactly in each animal, being modified by parameters such as the age at infection, the genotype, the breed or the causative strain. Moreover, different TSE strains can target different animal species or tissues, what complicate the prediction of its transmissibility when is tested in a different species of the origin source. The aim of the experimental studies in large animals is to homogenize all those factors, trying to minimize as much as possible variations between individuals. These effects can be flattened by experimental transmission in mice, in which a specific strain can be selected after several passages. With this objective, several experimental studies in large animals have been developed by the presenter research team. 

Classical scrapie agent has been inoculated in cow, with the aim of demonstrate the resistance or susceptibility of this species to the first well known TSE; Atypical scrapie has been inoculated in sheep (using several routes of infection), cow and pig, with the objective of evaluating the potential pathogenicity of this strain; Classical Bovine Spongiform Encephalopathy (BSE) has been inoculated in goats aiming to demonstrate if the genetic background of this species could protect against this strain; goat BSE and sheep BSE have been inoculated in goats and pigs respectively to evaluate the effect of species barrier; and finally atypical BSE has been inoculated in cattle to assess the transmissibility properties of this newly introduced strain. 

Once the experiments have been carried out on large animal species, a collection of samples from animals studied were inoculated in different types of tg mice overexpressing PrPcin order to study the infectivity of the tissues, and also were studied using PMCA. 

In summary, the parameters that have been controlled are the species, the strain, the route of inoculation, the time at infection, the genotype, the age, and the environmental conditions. 

To date, 

***> eleven of the atypical scrapie intracerebrally inoculated sheep have succumbed to atypical scrapie disease; 

***> six pigs to sheep BSE; 

***> one cow to classical scrapie; 

***> nine goats to goat BSE and 

***> five goats to classical BSE. 

***> PrPSC has been demonstrated in all cases by immunohistochemistry and western blot. 


=====> PRION CONFERENCE 2018


https://prion2018.org/

ZOONOSIS OF SCRAPIE TSE PRION

 O.05: Transmission of prions to primates after extended silent incubation periods: Implications for BSE and scrapie risk assessment in human populations 

Emmanuel Comoy, Jacqueline Mikol, Valerie Durand, Sophie Luccantoni, Evelyne Correia, Nathalie Lescoutra, Capucine Dehen, and Jean-Philippe Deslys Atomic Energy Commission; Fontenay-aux-Roses, France 

Prion diseases (PD) are the unique neurodegenerative proteinopathies reputed to be transmissible under field conditions since decades. The transmission of Bovine Spongiform Encephalopathy (BSE) to humans evidenced that an animal PD might be zoonotic under appropriate conditions. Contrarily, in the absence of obvious (epidemiological or experimental) elements supporting a transmission or genetic predispositions, PD, like the other proteinopathies, are reputed to occur spontaneously (atpical animal prion strains, sporadic CJD summing 80% of human prion cases). 

Non-human primate models provided the first evidences supporting the transmissibiity of human prion strains and the zoonotic potential of BSE. Among them, cynomolgus macaques brought major information for BSE risk assessment for human health (Chen, 2014), according to their phylogenetic proximity to humans and extended lifetime. We used this model to assess the zoonotic potential of other animal PD from bovine, ovine and cervid origins even after very long silent incubation periods. 

*** We recently observed the direct transmission of a natural classical scrapie isolate to macaque after a 10-year silent incubation period, 

***with features similar to some reported for human cases of sporadic CJD, albeit requiring fourfold long incubation than BSE. Scrapie, as recently evoked in humanized mice (Cassard, 2014), 

***is the third potentially zoonotic PD (with BSE and L-type BSE), 

***thus questioning the origin of human sporadic cases. 

We will present an updated panorama of our different transmission studies and discuss the implications of such extended incubation periods on risk assessment of animal PD for human health. 

=============== 

***thus questioning the origin of human sporadic cases*** 

=============== 

***our findings suggest that possible transmission risk of H-type BSE to sheep and human. Bioassay will be required to determine whether the PMCA products are infectious to these animals. 

============== https://prion2015.files.wordpress.com/2015/05/prion2015abstracts.pdf 

***Transmission data also revealed that several scrapie prions propagate in HuPrP-Tg mice with efficiency comparable to that of cattle BSE. While the efficiency of transmission at primary passage was low, subsequent passages resulted in a highly virulent prion disease in both Met129 and Val129 mice. 

***Transmission of the different scrapie isolates in these mice leads to the emergence of prion strain phenotypes that showed similar characteristics to those displayed by MM1 or VV2 sCJD prion. 

***These results demonstrate that scrapie prions have a zoonotic potential and raise new questions about the possible link between animal and human prions. http://www.tandfonline.com/doi/abs/10.1080/19336896.2016.1163048?journalCode=kprn20 


PRION 2016 TOKYO

Saturday, April 23, 2016

SCRAPIE WS-01: Prion diseases in animals and zoonotic potential 2016

Prion. 10:S15-S21. 2016 ISSN: 1933-6896 printl 1933-690X online

Taylor & Francis

Prion 2016 Animal Prion Disease Workshop Abstracts

WS-01: Prion diseases in animals and zoonotic potential

Juan Maria Torres a, Olivier Andreoletti b, J uan-Carlos Espinosa a. Vincent Beringue c. Patricia Aguilar a,

Natalia Fernandez-Borges a. and Alba Marin-Moreno a

"Centro de Investigacion en Sanidad Animal ( CISA-INIA ). Valdeolmos, Madrid. Spain; b UMR INRA -ENVT 1225 Interactions Holes Agents Pathogenes. ENVT. Toulouse. France: "UR892. Virologie lmmunologie MolécuIaires, Jouy-en-Josas. France

Dietary exposure to bovine spongiform encephalopathy (BSE) contaminated bovine tissues is considered as the origin of variant Creutzfeldt Jakob (vCJD) disease in human. To date, BSE agent is the only recognized zoonotic prion.. Despite the variety of Transmissible Spongiform Encephalopathy (TSE) agents that have been circulating for centuries in farmed ruminants there is no apparent epidemiological link between exposure to ruminant products and the occurrence of other form of TSE in human like sporadic Creutzfeldt Jakob Disease (sCJD). However, the zoonotic potential of the diversity of circulating TSE agents has never been systematically assessed. The major issue in experimental assessment of TSEs zoonotic potential lies in the modeling of the ‘species barrier‘, the biological phenomenon that limits TSE agents’ propagation from a species to another. In the last decade, mice genetically engineered to express normal forms of the human prion protein has proved essential in studying human prions pathogenesis and modeling the capacity of TSEs to cross the human species barrier.

To assess the zoonotic potential of prions circulating in farmed ruminants, we study their transmission ability in transgenic mice expressing human PrPC (HuPrP-Tg). Two lines of mice expressing different forms of the human PrPC (129Met or 129Val) are used to determine the role of the Met129Val dimorphism in susceptibility/resistance to the different agents.

These transmission experiments confirm the ability of BSE prions to propagate in 129M- HuPrP-Tg mice and demonstrate that Met129 homozygotes may be susceptible to BSE in sheep or goat to a greater degree than the BSE agent in cattle and that these agents can convey molecular properties and neuropathological indistinguishable from vCJD. However homozygous 129V mice are resistant to all tested BSE derived prions independently of the originating species suggesting a higher transmission barrier for 129V-PrP variant.

Transmission data also revealed that several scrapie prions propagate in HuPrP-Tg mice with efficiency comparable to that of cattle BSE. While the efficiency of transmission at primary passage was low, subsequent passages resulted in a highly virulent prion disease in both Met129 and Val129 mice. 

Transmission of the different scrapie isolates in these mice leads to the emergence of prion strain phenotypes that showed similar characteristics to those displayed by MM1 or VV2 sCJD prion. 

These results demonstrate that scrapie prions have a zoonotic potential and raise new questions about the possible link between animal and human prions. http://www.tandfonline.com/doi/abs/10.1080/19336896.2016.1163048?journalCode=kprn20


why do we not want to do TSE transmission studies on chimpanzees $

5. A positive result from a chimpanzee challenged severly would likely create alarm in some circles even if the result could not be interpreted for man. I have a view that all these agents could be transmitted provided a large enough dose by appropriate routes was given and the animals kept long enough. Until the mechanisms of the species barrier are more clearly understood it might be best to retain that hypothesis.

snip...

R. BRADLEYhttps://web.archive.org/web/20170126051158/http://collections.europarchive.org/tna/20080102222950/http://www.bseinquiry.gov.uk/files/yb/1990/09/23001001.pdf


Title: Transmission of scrapie prions to primate after an extended silent incubation period) 

*** In complement to the recent demonstration that humanized mice are susceptible to scrapie, we report here the first observation of direct transmission of a natural classical scrapie isolate to a macaque after a 10-year incubation period. Neuropathologic examination revealed all of the features of a prion disease: spongiform change, neuronal loss, and accumulation of PrPres throughout the CNS. 

*** This observation strengthens the questioning of the harmlessness of scrapie to humans, at a time when protective measures for human and animal health are being dismantled and reduced as c-BSE is considered controlled and being eradicated. 

*** Our results underscore the importance of precautionary and protective measures and the necessity for long-term experimental transmission studies to assess the zoonotic potential of other animal prion strains. http://www.ars.usda.gov/research/publications/publications.htm?SEQ_NO_115=313160

***> Moreover, sporadic disease has never been observed in breeding colonies or primate research laboratories, most notably among hundreds of animals over several decades of study at the National Institutes of Health25, and in nearly twenty older animals continuously housed in our own facility. <***

Transmission of scrapie prions to primate after an extended silent incubation period 

Emmanuel E. Comoy, Jacqueline Mikol, Sophie Luccantoni-Freire, Evelyne Correia, Nathalie Lescoutra-Etchegaray, Valérie Durand, Capucine Dehen, Olivier Andreoletti, Cristina Casalone, Juergen A. Richt, Justin J. Greenlee, Thierry Baron, Sylvie L. Benestad, Paul Brown & Jean-Philippe Deslys Scientific Reports volume 5, Article number: 11573 (2015) | Download Citation

Abstract 

Classical bovine spongiform encephalopathy (c-BSE) is the only animal prion disease reputed to be zoonotic, causing variant Creutzfeldt-Jakob disease (vCJD) in humans and having guided protective measures for animal and human health against animal prion diseases. Recently, partial transmissions to humanized mice showed that the zoonotic potential of scrapie might be similar to c-BSE. We here report the direct transmission of a natural classical scrapie isolate to cynomolgus macaque, a highly relevant model for human prion diseases, after a 10-year silent incubation period, with features similar to those reported for human cases of sporadic CJD. Scrapie is thus actually transmissible to primates with incubation periods compatible with their life expectancy, although fourfold longer than BSE. Long-term experimental transmission studies are necessary to better assess the zoonotic potential of other prion diseases with high prevalence, notably Chronic Wasting Disease of deer and elk and atypical/Nor98 scrapie.

SNIP...


Discussion We describe the transmission of spongiform encephalopathy in a non-human primate inoculated 10 years earlier with a strain of sheep c-scrapie. Because of this extended incubation period in a facility in which other prion diseases are under study, we are obliged to consider two alternative possibilities that might explain its occurrence. We first considered the possibility of a sporadic origin (like CJD in humans). Such an event is extremely improbable because the inoculated animal was 14 years old when the clinical signs appeared, i.e. about 40% through the expected natural lifetime of this species, compared to a peak age incidence of 60–65 years in human sporadic CJD, or about 80% through their expected lifetimes. Moreover, sporadic disease has never been observed in breeding colonies or primate research laboratories, most notably among hundreds of animals over several decades of study at the National Institutes of Health25, and in nearly twenty older animals continuously housed in our own facility.

The second possibility is a laboratory cross-contamination. Three facts make this possibility equally unlikely. First, handling of specimens in our laboratory is performed with fastidious attention to the avoidance of any such cross-contamination. Second, no laboratory cross-contamination has ever been documented in other primate laboratories, including the NIH, even between infected and uninfected animals housed in the same or adjacent cages with daily intimate contact (P. Brown, personal communication). Third, the cerebral lesion profile is different from all the other prion diseases we have studied in this model19, with a correlation between cerebellar lesions (massive spongiform change of Purkinje cells, intense PrPres staining and reactive gliosis26) and ataxia. The iron deposits present in the globus pallidus are a non specific finding that have been reported previously in neurodegenerative diseases and aging27. Conversely, the thalamic lesion was reminiscent of a metabolic disease due to thiamine deficiency28 but blood thiamine levels were within normal limits (data not shown). The preferential distribution of spongiform change in cortex associated with a limited distribution in the brainstem is reminiscent of the lesion profile in MM2c and VV1 sCJD patients29, but interspecies comparison of lesion profiles should be interpreted with caution. It is of note that the same classical scrapie isolate induced TSE in C57Bl/6 mice with similar incubation periods and lesional profiles as a sample derived from a MM1 sCJD patient30.

We are therefore confident that the illness in this cynomolgus macaque represents a true transmission of a sheep c-scrapie isolate directly to an old-world monkey, which taxonomically resides in the primate subdivision (parvorder of catarrhini) that includes humans. With an homology of its PrP protein with humans of 96.4%31, cynomolgus macaque constitutes a highly relevant model for assessing zoonotic risk of prion diseases. Since our initial aim was to show the absence of transmission of scrapie to macaques in the worst-case scenario, we obtained materials from a flock of naturally-infected sheep, affecting animals with different genotypes32. This c-scrapie isolate exhibited complete transmission in ARQ/ARQ sheep (332 ± 56 days) and Tg338 transgenic mice expressing ovine VRQ/VRQ prion protein (220 ± 5 days) (O. Andreoletti, personal communication). From the standpoint of zoonotic risk, it is important to note that sheep with c-scrapie (including the isolate used in our study) have demonstrable infectivity throughout their lymphoreticular system early in the incubation period of the disease (3 months-old for all the lymphoid organs, and as early as 2 months-old in gut-associated lymph nodes)33. In addition, scrapie infectivity has been identified in blood34, milk35 and skeletal muscle36 from asymptomatic but scrapie infected small ruminants which implies a potential dietary exposure for consumers.

Two earlier studies have reported the occurrence of clinical TSE in cynomolgus macaques after exposures to scrapie isolates. In the first study, the “Compton” scrapie isolate (derived from an English sheep) and serially propagated for 9 passages in goats did not transmit TSE in cynomolgus macaque, rhesus macaque or chimpanzee within 7 years following intracerebral challenge1; conversely, after 8 supplementary passages in conventional mice, this “Compton” isolate induced TSE in a cynomolgus macaque 5 years after intracerebral challenge, but rhesus macaques and chimpanzee remained asymptomatic 8.5 years post-exposure8. However, multiple successive passages that are classically used to select laboratory-adapted prion strains can significantly modify the initial properties of a scrapie isolate, thus questioning the relevance of zoonotic potential for the initial sheep-derived isolate. The same isolate had also induced disease into squirrel monkeys (new-world monkey)9. A second historical observation reported that a cynomolgus macaque developed TSE 6 years post-inoculation with brain homogenate from a scrapie-infected Suffolk ewe (derived from USA), whereas a rhesus macaque and a chimpanzee exposed to the same inoculum remained healthy 9 years post-exposure1. This inoculum also induced TSE in squirrel monkeys after 4 passages in mice. Other scrapie transmission attempts in macaque failed but had more shorter periods of observation in comparison to the current study. Further, it is possible that there are differences in the zoonotic potential of different scrapie strains.

The most striking observation in our study is the extended incubation period of scrapie in the macaque model, which has several implications. Firstly, our observations constitute experimental evidence in favor of the zoonotic potential of c-scrapie, at least for this isolate that has been extensively studied32,33,34,35,36. The cross-species zoonotic ability of this isolate should be confirmed by performing duplicate intracerebral exposures and assessing the transmissibility by the oral route (a successful transmission of prion strains through the intracerebral route may not necessarily indicate the potential for oral transmission37). However, such confirmatory experiments may require more than one decade, which is hardly compatible with current general management and support of scientific projects; thus this study should be rather considered as a case report.

Secondly, transmission of c-BSE to primates occurred within 8 years post exposure for the lowest doses able to transmit the disease (the survival period after inoculation is inversely proportional to the initial amount of infectious inoculum). The occurrence of scrapie 10 years after exposure to a high dose (25 mg) of scrapie-infected sheep brain suggests that the macaque has a higher species barrier for sheep c-scrapie than c-BSE, although it is notable that previous studies based on in vitro conversion of PrP suggested that BSE and scrapie prions would have a similar conversion potential for human PrP38.

Thirdly, prion diseases typically have longer incubation periods after oral exposure than after intracerebral inoculations: since humans can develop Kuru 47 years after oral exposure39, an incubation time of several decades after oral exposure to scrapie would therefore be expected, leading the disease to occur in older adults, i.e. the peak age for cases considered to be sporadic disease, and making a distinction between scrapie-associated and truly sporadic disease extremely difficult to appreciate.

Fourthly, epidemiologic evidence is necessary to confirm the zoonotic potential of an animal disease suggested by experimental studies. A relatively short incubation period and a peculiar epidemiological situation (e.g., all the first vCJD cases occurring in the country with the most important ongoing c-BSE epizootic) led to a high degree of suspicion that c-BSE was the cause of vCJD. Sporadic CJD are considered spontaneous diseases with an almost stable and constant worldwide prevalence (0.5–2 cases per million inhabitants per year), and previous epidemiological studies were unable to draw a link between sCJD and classical scrapie6,7,40,41, even though external causes were hypothesized to explain the occurrence of some sCJD clusters42,43,44. However, extended incubation periods exceeding several decades would impair the predictive values of epidemiological surveillance for prion diseases, already weakened by a limited prevalence of prion diseases and the multiplicity of isolates gathered under the phenotypes of “scrapie” and “sporadic CJD”.

Fifthly, considering this 10 year-long incubation period, together with both laboratory and epidemiological evidence of decade or longer intervals between infection and clinical onset of disease, no premature conclusions should be drawn from negative transmission studies in cynomolgus macaques with less than a decade of observation, as in the aforementioned historical transmission studies of scrapie to primates1,8,9. Our observations and those of others45,46 to date are unable to provide definitive evidence regarding the zoonotic potential of CWD, atypical/Nor98 scrapie or H-type BSE. The extended incubation period of the scrapie-affected macaque in the current study also underscores the limitations of rodent models expressing human PrP for assessing the zoonotic potential of some prion diseases since their lifespan remains limited to approximately two years21,47,48. This point is illustrated by the fact that the recently reported transmission of scrapie to humanized mice was not associated with clinical signs for up to 750 days and occurred in an extreme minority of mice with only a marginal increase in attack rate upon second passage13. The low attack rate in these studies is certainly linked to the limited lifespan of mice compared to the very long periods of observation necessary to demonstrate the development of scrapie. Alternatively, one could estimate that a successful second passage is the result of strain adaptation to the species barrier, thus poorly relevant of the real zoonotic potential of the original scrapie isolate of sheep origin49. The development of scrapie in this primate after an incubation period compatible with its lifespan complements the study conducted in transgenic (humanized) mice; taken together these studies suggest that some isolates of sheep scrapie can promote misfolding of the human prion protein and that scrapie can develop within the lifespan of some primate species.

In addition to previous studies on scrapie transmission to primate1,8,9 and the recently published study on transgenic humanized mice13, our results constitute new evidence for recommending that the potential risk of scrapie for human health should not be dismissed. Indeed, human PrP transgenic mice and primates are the most relevant models for investigating the human transmission barrier. To what extent such models are informative for measuring the zoonotic potential of an animal TSE under field exposure conditions is unknown. During the past decades, many protective measures have been successfully implemented to protect cattle from the spread of c-BSE, and some of these measures have been extended to sheep and goats to protect from scrapie according to the principle of precaution. Since cases of c-BSE have greatly reduced in number, those protective measures are currently being challenged and relaxed in the absence of other known zoonotic animal prion disease. We recommend that risk managers should be aware of the long term potential risk to human health of at least certain scrapie isolates, notably for lymphotropic strains like the classical scrapie strain used in the current study. Relatively high amounts of infectivity in peripheral lymphoid organs in animals infected with these strains could lead to contamination of food products produced for human consumption. Efforts should also be maintained to further assess the zoonotic potential of other animal prion strains in long-term studies, notably lymphotropic strains with high prevalence like CWD, which is spreading across North America, and atypical/Nor98 scrapie (Nor98)50 that was first detected in the past two decades and now represents approximately half of all reported cases of prion diseases in small ruminants worldwide, including territories previously considered as scrapie free.. Even if the prevailing view is that sporadic CJD is due to the spontaneous formation of CJD prions, it remains possible that its apparent sporadic nature may, at least in part, result from our limited capacity to identify an environmental origin.


Singeltary on Scrapie and human transmission way back, see;


why do we not want to do TSE transmission studies on chimpanzees $

5. A positive result from a chimpanzee challenged severly would likely create alarm in some circles even if the result could not be interpreted for man. I have a view that all these agents could be transmitted provided a large enough dose by appropriate routes was given and the animals kept long enough. Until the mechanisms of the species barrier are more clearly understood it might be best to retain that hypothesis.

snip...

R. BRADLEY



BSE INQUIRY
1979
SILENCE ON CJD AND SCRAPIE
1980
SILENCE ON CJD AND SCRAPIE
*** 1981 NOVEMBER

1: J Infect Dis 1980 Aug;142(2):205-8
Oral transmission of kuru, Creutzfeldt-Jakob disease, and scrapie to nonhuman primates.
Gibbs CJ Jr, Amyx HL, Bacote A, Masters CL, Gajdusek DC.
Kuru and Creutzfeldt-Jakob disease of humans and scrapie disease of sheep and goats were transmitted to squirrel monkeys (Saimiri sciureus) that were exposed to the infectious agents only by their nonforced consumption of known infectious tissues. The asymptomatic incubation period in the one monkey exposed to the virus of kuru was 36 months; that in the two monkeys exposed to the virus of Creutzfeldt-Jakob disease was 23 and 27 months, respectively; and that in the two monkeys exposed to the virus of scrapie was 25 and 32 months, respectively. Careful physical examination of the buccal cavities of all of the monkeys failed to reveal signs or oral lesions. One additional monkey similarly exposed to kuru has remained asymptomatic during the 39 months that it has been under observation.
snip...
The successful transmission of kuru, Creutzfeldt-Jakob disease, and scrapie by natural feeding to squirrel monkeys that we have reported provides further grounds for concern that scrapie-infected meat may occasionally give rise in humans to Creutzfeldt-Jakob disease.
PMID: 6997404
12/10/76
AGRICULTURAL RESEARCH COUNCIL REPORT OF THE ADVISORY COMMITTE ON SCRAPIE
Office Note CHAIRMAN: PROFESSOR PETER WILDY
snip...
A The Present Position with respect to Scrapie A] The Problem Scrapie is a natural disease of sheep and goats. It is a slow and inexorably progressive degenerative disorder of the nervous system and it ia fatal. It is enzootic in the United Kingdom but not in all countries. The field problem has been reviewed by a MAFF working group (ARC 35/77). It is difficult to assess the incidence in Britain for a variety of reasons but the disease causes serious financial loss; it is estimated that it cost Swaledale breeders alone $l.7 M during the five years 1971-1975. A further inestimable loss arises from the closure of certain export markets, in particular those of the United States, to British sheep. It is clear that scrapie in sheep is important commercially and for that reason alone effective measures to control it should be devised as quickly as possible. Recently the question has again been brought up as to whether scrapie is transmissible to man. This has followed reports that the disease has been transmitted to primates.
One particularly lurid speculation (Gajdusek 1977) conjectures that the agents of scrapie, kuru, Creutzfeldt-Jakob disease and transmissible encephalopathy of mink are varieties of a single "virus". The U.S. Department of Agriculture concluded that it could "no longer justify or permit scrapie-blood line and scrapie-exposed sheep and goats to be processed for human or animal food at slaughter or rendering plants" (ARC 84/77)" The problem is emphasised by the finding that some strains of scrapie produce lesions identical to the once which characterise the human dementias" Whether true or not. the hypothesis that these agents might be transmissible to man raises two considerations. First, the safety of laboratory personnel requires prompt attention. Second, action such as the "scorched meat" policy of USDA makes the solution of the acrapie problem urgent if the sheep industry is not to suffer grievously.
snip...
76/10.12/4.6
Nature. 1972 Mar 10;236(5341):73-4.
Transmission of scrapie to the cynomolgus monkey (Macaca fascicularis).
Gibbs CJ Jr, Gajdusek DC. Nature 236, 73 - 74 (10 March 1972); doi:10.1038/236073a0
Transmission of Scrapie to the Cynomolgus Monkey (Macaca fascicularis)
C. J. GIBBS jun. & D. C. GAJDUSEK National Institute of Neurological Diseases and Stroke, National Institutes of Health, Bethesda, Maryland
SCRAPIE has been transmitted to the cynomolgus, or crab-eating, monkey (Macaca fascicularis) with an incubation period of more than 5 yr from the time of intracerebral inoculation of scrapie-infected mouse brain. The animal developed a chronic central nervous system degeneration, with ataxia, tremor and myoclonus with associated severe scrapie-like pathology of intensive astroglial hypertrophy and proliferation, neuronal vacuolation and status spongiosus of grey matter. The strain of scrapie virus used was the eighth passage in Swiss mice (NIH) of a Compton strain of scrapie obtained as ninth intracerebral passage of the agent in goat brain, from Dr R. L. Chandler (ARC, Compton, Berkshire).
Nature. 1972 Mar 10;236(5341):73-4.
Transmission of scrapie to the cynomolgus monkey (Macaca fascicularis).
Gibbs CJ Jr, Gajdusek DC. Nature 236, 73 - 74 (10 March 1972); doi:10.1038/236073a0
Transmission of Scrapie to the Cynomolgus Monkey (Macaca fascicularis)
C. J. GIBBS jun. & D. C. GAJDUSEK National Institute of Neurological Diseases and Stroke, National Institutes of Health, Bethesda, Maryland
SCRAPIE has been transmitted to the cynomolgus, or crab-eating, monkey (Macaca fascicularis) with an incubation period of more than 5 yr from the time of intracerebral inoculation of scrapie-infected mouse brain. The animal developed a chronic central nervous system degeneration, with ataxia, tremor and myoclonus with associated severe scrapie-like pathology of intensive astroglial hypertrophy and proliferation, neuronal vacuolation and status spongiosus of grey matter. The strain of scrapie virus used was the eighth passage in Swiss mice (NIH) of a Compton strain of scrapie obtained as ninth intracerebral passage of the agent in goat brain, from Dr R. L. Chandler (ARC, Compton, Berkshire).
why do we not want to do TSE transmission studies on chimpanzees $
IN CONFIDENCE
TRANSMISSION TO CHIMPANZEES
snip...
5. A positive result from a chimpanzee challenged severely would likely create alarm in some circles even if the result could not be interpreted for man. I have a view that all these agents could be transmitted provided a large enough dose by appropriate routes was given and the animals kept long enough. Until the mechanisms of the species barrier are more clearly understood it might be best to retain that hypothesis.
snip...
R. BRADLEY
full text ;
RB3.20
IN CONFIDENCE
TRANSMISSION TO CHIMPANZEE
1. Kuru and CJD have been successfully transmitted to chimpanzees but scrapie and TME have not.
2. We cannot say that scrapie will not transmit to chimpanzees. There are several scrapie strains and I am not aware that all have been tried (that would have to be from mouse passaged material). Nor has a wide enough range of field isolates subsequently strain typed in mice been inoculated by the appropriate routes (i/c, i/p and i v);
3. I believe the proposed experiment to determine transmissibility, if conducted, would only show the susceptibility or resistance of the chimpanzee to infection/disease by the routes used and the result could not be interpreted for the predictability of the susceptibility for man. Proposals for prolonged oral exposure of chimpanzees to milk from cattle were suggested a long while ago and rejected.
4. In view of Dr Gibbs‘ probable use of Chimpazees Mr Wells‘ comments (enclosed) are pertinent. I have yet to receive a direct communication from Dr Schellekers but before any collaboration or provision of material we should identify the Gibbs' proposals and objectives.
5. A positive result from a chimpanzee challenged severely would likely create alarm in some circles even if the result could not be interpreted for man. I have a view that all these agents could be transmitted provided a large enough dose by appropriate routes was given and the animals kept long enough. Until the mechanisms of the species barrier are more clearly understood it might be best to retain that hypothesis.
A negative result would take a lifetime to determine but that would be a shorter period than might be available for human exposure and it would still not answer the question regarding mans' susceptibility. In the meantime no doubt the negativity would be used defensively. It would however be counterproductive if the experiment finally became positive- We may learn more about public reactions following next Monday‘s meeting. CVO (+ Mr. Wells’ comments)
Dr. T W A Little
Dr. B J Shreeve
R Bradley September 1990
90/9.23/1/1
Wednesday, February 16, 2011
IN CONFIDENCE
SCRAPIE TRANSMISSION TO CHIMPANZEES
IN CONFIDENCE

Unexpected prion phenotypes in experimentally transfused animals: predictive models for humans? 

Emmanuel E. Comoy, Jacqueline Mikol & Jean-Philippe Deslys 

Pages 162-169 | Received 06 Jul 2018, Accepted 24 Jul 2018, Accepted author version posted online: 06 Aug 2018, Published online: 16 Aug 2018

ABSTRACT 

The recently reevaluated high prevalence of healthy carriers (1/2,000 in UK) of variant Creutzfeldt-Jakob Disease (v-CJD), whose blood might be infectious, suggests that the evolution of this prion disease might not be under full control as expected. 

After experimental transfusion of macaques and conventional mice with blood derived from v-CJD exposed (human and animal) individuals, we confirmed in these both models the transmissibility of v-CJD, but we also observed unexpected neurological syndromes transmissible by transfusion: despite their prion etiology confirmed through transmission experiments, these original cases would escape classical prion diagnosis, notably in the absence of detectable abnormal PrP with current techniques. 

It is noteworthy that macaques developed an original, yet undescribed myelopathic syndrome associating demyelination and pseudo-necrotic lesions of spinal cord, brainstem and optical tract without affecting encephalon, which is rather evocative of spinal cord disease than prion disease in human medicine. 

These observations strongly suggest that the spectrum of human prion diseases may extend the current field restricted to the phenotypes associated to protease-resistant PrP, and may notably include spinal cord diseases.

KEYWORDS: (5-10): prion, vCJD, macaque, mouse, spinal cord disease, myelopathy, transfusion, abnormal PrP, demyelination, spongiform change

This article refers to:

Additional information

Funding

The original laboratory work was funded by European Commission [Fifth Framework Programme, QLK1-CT-2002-01096], French Research Funding Agency (Agence Nationale de la Recherche, ANR) [ANR-10-BLAN-1330 01], Health Canada [4500216567] and MacoPharma.



***> It is noteworthy that macaques developed an original, yet undescribed myelopathic syndrome associating demyelination and pseudo-necrotic lesions of spinal cord, brainstem and optical tract without affecting encephalon, which is rather evocative of spinal cord disease than prion disease in human medicine. 

***> These observations strongly suggest that the spectrum of human prion diseases may extend the current field restricted to the phenotypes associated to protease-resistant PrP, and may notably include spinal cord diseases.


TUESDAY, AUGUST 7, 2018 

Unexpected prion phenotypes in experimentally transfused animals: predictive models for humans?

http://transmissiblespongiformencephalopathy.blogspot.com/2018/08/unexpected-prion-phenotypes-in.html


MONDAY, NOVEMBER 06, 2017 

Experimental transfusion of variant CJD-infected blood reveals previously uncharacterised prion disorder in mice and macaque

http://vcjd.blogspot.com/2017/11/experimental-transfusion-of-variant-cjd.html


FRIDAY, OCTOBER 05, 2018

More Politicians and Very Young People Struck Down With Creutzfeldt Jakob Disease CJD mad cow type TSE Prion USA

https://creutzfeldt-jakob-disease.blogspot.com/2018/10/more-politicians-and-very-young-people.html


Sunday, September 16, 2018 

Mother to Offspring Transmission of TSE PRION DISEASE and risk factors there from

http://prionprp.blogspot.com/2018/09/mother-to-offspring-transmission-of-tse.html


WEDNESDAY, SEPTEMBER 05, 2018 

Edmonton woman one of the youngest diagnosed with CJD at 35 years old and pregnant



Volume 2: Science 

4. The link between BSE and vCJD 

Summary 

4.29 The evidence discussed above that vCJD is caused by BSE seems overwhelming. Uncertainties exist about the cause of CJD in farmers, their wives and in several abattoir workers. It seems that farmers at least might be at higher risk than others in the general population. 1 Increased ascertainment (ie, increased identification of cases as a result of greater awareness of the condition) seems unlikely, as other groups exposed to risk, such as butchers and veterinarians, do not appear to have been affected. 

***The CJD in farmers seems to be similar to other sporadic CJD in age of onset, in respect to glycosylation patterns, and in strain-typing in experimental mice. 

***Some farmers are heterozygous for the methionine/valine variant at codon 129, and their lymphoreticular system (LRS) does not contain the high levels of PrPSc found in vCJD. 

*** It remains a remote possibility that when older people contract CJD from BSE the resulting phenotype is like sporadic CJD and is distinct from the vCJD phenotype in younger people.

BSEINQUIRY


***>Some farmers are heterozygous for the methionine/valine variant at codon 129, and their lymphoreticular system (LRS) does not contain the high levels of PrPSc found in vCJD.<***


SATURDAY, JUNE 23, 2018

***> Diagnosis of Methionine/Valine Variant Creutzfeldt-Jakob Disease by Protein Misfolding Cyclic Amplification

Volume 24, Number 7—July 2018



2006-2007

HUMAN and ANIMAL TSE Classifications i.e. mad cow disease and the UKBSEnvCJD only theory

TSEs have been rampant in the USA for decades in many species, and they all have been rendered and fed back to animals for human/animal consumption. I propose that the current diagnostic criteria for human TSEs only enhances and helps the spreading of human TSE from the continued belief of the UKBSEnvCJD only theory in 2007. With all the science to date refuting it, to continue to validate this myth, will only spread this TSE agent through a multitude of potential routes and sources i.e. consumption, surgical, blood, medical, cosmetics etc. I propose as with Aguzzi, Asante, Collinge, Caughey, Deslys, Dormont, Gibbs, Ironside, Manuelidis, Marsh, et al and many more, that the world of TSE Transmissible Spongiform Encephalopathy is far from an exact science, but there is enough proven science to date that this myth should be put to rest once and for all, and that we move forward with a new classification for human and animal TSE that would properly identify the infected species, the source species, and then the route. This would further have to be broken down to strain of species and then the route of transmission would further have to be broken down. Accumulation and Transmission are key to the threshold from subclinical to clinical disease, and of that, I even believe that physical and or blunt trauma may play a role of onset of clinical symptoms in some cases, but key to all this, is to stop the amplification and transmission of this agent, the spreading of, no matter what strain. BUT, to continue with this myth that the U.K. strain of BSE one strain in cows, and the nv/v CJD, one strain in humans, and that all the rest of human TSE is one single strain i.e. sporadic CJD (when to date there are 6 different phenotypes of sCJD), and that no other animal TSE transmits to humans, to continue with this masquerade will only continue to spread, expose, and kill, who knows how many more in the years and decades to come. ONE was enough for me, My Mom, hvCJD, DOD 12/14/97 confirmed, which is nothing more than another mans name added to CJD, like CJD itself, Jakob and Creutzfeldt, or Gerstmann-Straussler-Scheinker syndrome, just another CJD or human TSE, named after another human. WE are only kidding ourselves with the current diagnostic criteria for human and animal TSE, especially differentiating between the nvCJD vs the sporadic CJD strains and then the GSS strains and also the FFI fatal familial insomnia strains or the ones that mimics one or the other of those TSE? Tissue infectivity and strain typing of the many variants of the human and animal TSEs are paramount in all variants of all TSE. There must be a proper classification that will differentiate between all these human TSE in order to do this. With the CDI and other more sensitive testing coming about, I only hope that my proposal will some day be taken seriously.

My name is Terry S. Singeltary Sr. and I am no scientist, no doctor and have no PhDs, but have been independently researching human and animal TSEs since the death of my Mother to the Heidenhain Variant of Creutzfeldt Jakob Disease on December 14, 1997 'confirmed'. ...END

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. 


Diagnosis and Reporting of Creutzfeldt-Jakob Disease

Singeltary, Sr et al. JAMA.2001; 285: 733-734.


BRITISH MEDICAL JOURNAL

BMJ

U.S. Scientist should be concerned with a CJD epidemic in the U.S., as well...

02 January 2000

Terry S Singeltary

retired


US scientists develop a possible test for BSE

BMJ 1999; 319 doi: https://doi.org/10.1136/bmj.319.7220.1312b (Published 13 November 1999) Cite this as: BMJ 1999;319:1312

Rapid responses Response

Re: vCJD in the USA * BSE in U.S.

15 November 1999

Terry S Singeltary

NA

medically retired


January 28, 2003; 60 (2) VIEWS & REVIEWS

Monitoring the occurrence of emerging forms of Creutzfeldt-Jakob disease in the United States

Ermias D. Belay, Ryan A. Maddox, Pierluigi Gambetti, Lawrence B. Schonberger

First published January 28, 2003, DOI: https://doi.org/10.1212/01.WNL.0000036913.87823.D6

Abstract

Transmissible spongiform encephalopathies (TSEs) attracted increased attention in the mid-1980s because of the emergence among UK cattle of bovine spongiform encephalopathy (BSE), which has been shown to be transmitted to humans, causing a variant form of Creutzfeldt-Jakob disease (vCJD). The BSE outbreak has been reported in 19 European countries, Israel, and Japan, and human cases have so far been identified in four European countries, and more recently in a Canadian resident and a US resident who each lived in Britain during the BSE outbreak. To monitor the occurrence of emerging forms of CJD, such as vCJD, in the United States, the Centers for Disease Control and Prevention has been conducting surveillance for human TSEs through several mechanisms, including the establishment of the National Prion Disease Pathology Surveillance Center. Physicians are encouraged to maintain a high index of suspicion for vCJD and use the free services of the pathology center to assess the neuropathology of clinically diagnosed and suspected cases of CJD or other TSEs.

Received May 7, 2002. Accepted August 28, 2002.


RE-Monitoring the occurrence of emerging forms of Creutzfeldt-Jakob disease in the United States 

Terry S. Singeltary, retired (medically) 

Published March 26, 2003

26 March 2003

Terry S. Singeltary, retired (medically) CJD WATCH

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 [1] 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 by 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?


Reply to Singletary Ryan A. Maddox, MPH Other Contributors: Published March 26, 2003 

Mr. Singletary raises several issues related to current Creutzfeldt- Jakob disease (CJD) surveillance activities. Although CJD is not a notifiable disease in most states, its unique characteristics, particularly its invariably fatal outcome within usually a year of onset, make routine mortality surveillance a useful surrogate for ongoing CJD surveillance.[1] In addition, because CJD is least accurately diagnosed early in the course of illness, notifiable-disease surveillance could be less accurate than, if not duplicative of, current mortality surveillance.[1] However, in states where making CJD officially notifiable would meaningfully facilitate the collection of data to monitor for variant CJD (vCJD) or other emerging prion diseases, CDC encourages the designation of CJD as a notifiable disease.[1] Moreover, CDC encourages physicians to report any diagnosed or suspected CJD cases that may be of special public health importance (e.g., vCJD, iatrogenic CJD, unusual CJD clusters).

As noted in our article, strong evidence is lacking for a causal link between chronic wasting disease (CWD) of deer and elk and human disease,[2] but only limited data seeking such evidence exist. Overall, the previously published case-control studies that have evaluated environmental sources of infection for sporadic CJD have not consistently identified strong evidence for a common risk factor.[3] However, the power of a case-control study to detect a rare cause of CJD is limited, particularly given the relatively small number of subjects generally involved and its long incubation period, which may last for decades. Because only a very small proportion of the US population has been exposed to CWD, a targeted surveillance and investigation of unusual cases or case clusters of prion diseases among persons at increased risk of exposure to CWD is a more efficient approach to detecting the possible transmission of CWD to humans. In collaboration with appropriate local and state health departments and the National Prion Disease Pathology Surveillance Center, CDC is facilitating or conducting such surveillance and case- investigations, including related laboratory studies to characterize CJD and CWD prions.

Mr. Singletary also expresses concern over a recent publication by Asante and colleagues indicating the possibility that some sporadic CJD cases may be attributable to bovine spongiform encephalopathy (BSE).[4] The authors reported that transgenic mice expressing human prion protein homozygous for methionine at codon 129, when inoculated with BSE prions, developed a molecular phenotype consistent with a subtype of sporadic CJD. Although the authors implied that BSE might cause a sporadic CJD-like illness among persons homozygous for methionine, the results of their research with mice do not necessarily directly apply to the transmission of BSE to humans. If BSE causes a sporadic CJD-like illness in humans, an increase in sporadic CJD cases would be expected to first occur in the United Kingdom, where the vast majority of vCJD cases have been reported. In the United Kingdom during 1997 through 2002, however, the overall average annual mortality rate for sporadic CJD was not elevated; it was about 1 case per million population per year. In addition, during this most recent 6-year period following the first published description of vCJD in 1996, there was no increasing trend in the reported annual number of UK sporadic CJD deaths.[3, 5] Furthermore, surveillance in the UK has shown no increase in the proportion of sporadic CJD cases that are homozygous for methionine (Will RG, National CJD Surveillance Unit, United Kingdom, 2003; personal communication).

References

1. Gibbons RV, Holman RC, Belay ED, Schonberger LB. Diagnosis and reporting of Creutzfeldt-Jakob disease. JAMA 2001;285:733-734.

2. Belay ED, Maddox RA, Gambetti P, Schonberger LB. Monitoring the occurrence of emerging forms of Creutzfeldt-Jakob disease in the United States. Neurology 2003;60:176-181.

3. Belay ED. Transmissible spongiform encephalopathies in humans. Annu Rev Microbiol 1999;53:283-314.

4. Asante EA, Linehan JM, Desbruslais M, et al. BSE prions propagate as either variant CJD-like or sporadic CJD-like prion strains in transgenic mice expressing human prion protein. EMBO J 2002;21:6358-6366.

5. The UK Creutzfeldt-Jakob Disease Surveillance Unit. CJD statistics. Available at: http://www.cjd.ed.ac.uk/figures.htm. Accessed February 18, 2003.

Competing Interests: None declared.


doi:10.1016/S1473-3099(03)00715-1 Copyright © 2003 Published by Elsevier Ltd. Newsdesk

Tracking spongiform encephalopathies in North America

Xavier Bosch

Available online 29 July 2003. 

Volume 3, Issue 8, August 2003, Page 463 

“My name is Terry S Singeltary Sr, and I live in Bacliff, Texas. I lost my mom to hvCJD (Heidenhain variant CJD) and have been searching for answers ever since. What I have found is that we have not been told the truth. CWD in deer and elk is a small portion of a much bigger problem.” ............................ 




FRIDAY, JUNE 29, 2018

Vaccines, TSE, Prion, risk factors?


***> see HISTORY great debate here <*** 

BSE, CJD, and Baby foods (the great debate 1999 to 2005)


SATURDAY, OCTOBER 06, 2018 

Evaluation of iatrogenic risk of CJD transmission associated with corneal transplantation


SATURDAY, SEPTEMBER 22, 2018 

Emerging Diseases, Infection Control & California Dental Practice Act


THURSDAY, OCTOBER 04, 2018 

Case Western Reserve researchers to examine skin prions in fatal neurodegenerative disease $2.9 million NIH grant focuses on transmission and diagnostic testing


WEDNESDAY, JULY 04, 2018 

CREUTZFELDT-JAKOB DISEASE: GUIDELINES FOR SOCIAL WORKERS IN ENGLAND June 2018


MONDAY, JUNE 18, 2018

Ecuador Six Case series of Creutzfeldt-Jakob disease in a third-level hospital in Quito


THURSDAY, OCTOBER 04, 2018 

Cervid to human prion transmission 5R01NS088604-04 Update


WEDNESDAY, SEPTEMBER 26, 2018 

JAVMA In Short Update USDA announces detection of atypical BSE


MONDAY, OCTOBER 01, 2018 

Update on Classical and Atypical Scrapie in Sheep and Goats: Review 2018

http://scrapie-usa.blogspot.com/2018/10/update-on-classical-and-atypical.html

HUMAN MAD COW DISEASE nvCJD TEXAS CASE NOT LINKED TO EUROPEAN TRAVEL CDC

Sunday, November 23, 2014

Confirmed Variant Creutzfeldt-Jakob Disease (variant CJD) Case in Texas

Updated: October 7, 2014

CDC and the Texas Department of State Health Services (DSHS) have completed the investigation of the recently reported fourth vCJD case in the United States. It confirmed that the case was in a US citizen born outside the Americas and indicated that the patient's exposure to the BSE/vCJD agent most likely occurred before he moved to the United States; the patient had resided in Kuwait, Russia and Lebanon. The completed investigation did not support the patient's having had extended travel to European countries, including the United Kingdom, or travel to Saudi Arabia. The specific overseas country where this patient’s infection occurred is less clear largely because the investigation did not definitely link him to a country where other known vCJD cases likely had been infected.

https://www.cdc.gov/ncidod/dvrd/vcjd/other/confirmed-case-in-texas.htm

https://vcjd.blogspot.com/2014/11/confirmed-variant-creutzfeldt-jakob.html


WEDNESDAY, SEPTEMBER 26, 2018 

A new variant of Creutzfeldt-Jakob disease in the UK 1995 revisited 2018 a review of science


THURSDAY, OCTOBER 04, 2018 

National Prion Disease Pathology Surveillance Center Cases Examined¹ (September 18, 2018)


THURSDAY, SEPTEMBER 27, 2018 

Amydis Awarded Prion Disease Grant from NIH


TUESDAY, SEPTEMBER 4, 2018 

USA CJD, BSE, SCRAPIE, CWD, TSE PRION END OF YEAR REPORTS September 4, 2018

prepare for the storm...


Tuesday, March 20, 2018 

Variably protease-sensitive prionopathy (VPSPr), sporadic creutzfeldt jakob disease sCJD, the same disease, what if?






FRIDAY, NOVEMBER 09, 2018 

Minnesota Chronic Wasting Disease CWD TSE Prion Captive Cervid Farming SSS testing policy



CWD Update 121 November 05, 2018

http://cwd-info.org/wp-content/uploads/2018/11/Update-121.pdf


THURSDAY, OCTOBER 25, 2018 

***> Norway New additional requirements for imports of hay and straw for animal feed from countries outside the EEA due to CWD TSE Prion



FRIDAY, NOVEMBER 2, 2018 

MAD COW TYPE DISEASE BSE CWD SCRAPIE TSE PRION UPDATE



THURSDAY, OCTOBER 04, 2018 

***> Cervid to human prion transmission 5R01NS088604-04 Update




kindest regards, terry


Terry S. Singeltary Sr.

at

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