Chronic Wasting Disease

Transmission of cervid prions to humanized mice demonstrates the zoonotic potential of CWD

Samia Hannaoui1 · Irina Zemlyankina1 · Sheng Chun Chang1 · Maria Immaculata Arifn1 · Vincent Béringue2 · Debbie McKenzie3 · Hermann M. Schatzl1 · Sabine Gilch1

Received: 24 May 2022 / Revised: 5 August 2022 / Accepted: 7 August 2022

Abstract

Prions cause infectious and fatal neurodegenerative diseases in mammals. Chronic wasting disease (CWD), a prion disease of cervids, spreads efficiently among wild and farmed animals. Potential transmission to humans of CWD is a growing concern due to its increasing prevalence. Here, we provide evidence for a zoonotic potential of CWD prions, and its probable signature using mice expressing human prion protein (PrP) as an infection model. Inoculation of these mice with deer CWD isolates resulted in atypical clinical manifestation with prion seeding activity and efficient transmissible infectivity in the brain and, remarkably, in feces, but without classical neuropathological or Western blot appearances of prion diseases. Intriguingly, the protease-resistant PrP in the brain resembled that found in a familial human prion disease and was transmissible upon second passage. Our results suggest that CWD might infect humans, although the transmission barrier is likely higher compared to zoonotic transmission of cattle prions. Notably, our data suggest a different clinical presentation, prion signature, and tissue tropism, which causes challenges for detection by current diagnostic assays. Furthermore, the presence of infectious prions in feces is concerning because if this occurs in humans, it is a source for human-to-human transmission. These findings have strong implications for public health and CWD management.

Keywords Chronic wasting disease · CWD · Zoonotic potential · Prion strains · Zoonotic prions

Introduction

Prions are the causative agents of transmissible and fatal neurodegenerative diseases of humans [e.g., Creutzfeldt–Jakob disease (CJD)] and animals (scrapie in sheep, bovine spongiform encephalopathy (BSE) in cattle, and CWD in cervids) [17]. Prion diseases are characterized by the accumulation in the brain of the infectious prion protein, PrPSc, derived after a structural transition from its host-encoded, cellular isoform, PrPC [49]. CWD is the only prion disease known to affect both free-roaming and farmed animals. Cervid species naturally affected by CWD include white-tailed deer (WTD; Odocoileus virginianus), mule deer (O. hemionus), elk (Cervus canadensis), red deer (C. elaphus), moose (Alces alces sp.), and reindeer (Rangifer tarandus tarandus) [4]. As of today, it has been identified in 30 US states, with a prevalence as high as 40% in certain endemic areas [25], 4 Canadian provinces, South Korea, and 3 Northern European countries, Norway, Finland, and Sweden [4]. For most prion diseases, with the exception of scrapie and CWD, infectious prions are mostly confined to the central nervous system. In contrast, in cervids affected with CWD, infectivity has been found in the lymphatic system, salivary gland, intestinal tract, muscles, antler velvet, blood, urine, saliva, and feces [4], which have been demonstrated to be transmissible [57]. CWD prions are shed into the environment via bodily fluids and excreta. They bind to soil and are taken up by plants, making the environment infectious for decades to come [4, 48]. The persistence of CWD prions in the environment amplifies the already effective transmission within and between cervid species. Therefore, CWD is considered to be the most contagious prion disease with fast spreading and efficient horizontal transmission.

Zoonotic BSE (i.e., variant CJD; vCJD) provides undeniable evidence that animal prions can infect humans, resulting in distinct disease manifestation and strain properties [14]. Epidemiological studies in CWD endemic areas have neither indicated an increased incidence of CJD patients, nor unusual prion disease subtypes [8, 25, 28]. Numerous studies assessing the zoonotic potential of CWD, both in vitro and in vivo, overall conclude that the risk of CWD crossing the human barrier is low [5, 7, 28, 32, 34, 52, 53, 55, 56, 60, 61, 63]. However, prions are dynamic and evolving, and interspecies passage of CWD can result in prion adaptation to new host species. The existence of more than one CWD strain [4] may contribute to higher heterogeneity in disease and transmission profles. In vitro studies using protein misfolding cyclic amplification (PMCA) demonstrated that PrPCWD can convert human PrPC into PrPCWD; however, this was achieved efficiently only after prion strain stabilization and adaptation in vitro or in vivo [6, 7]. Efficiency of PMCA conversion also depended on a human PrP polymorphism at position 129 [methionine (M)/valine (V)], affecting susceptibility to prion disease in humans [5, 18, 42], especially in the only to date known human prion disease (vCJD) acquired after animal prions (BSE) crossed the species barrier [14]. In contrast, most in vivo studies indicated that inoculation of different CWD prion isolates into transgenic mice overexpressing human PrPC with different genotypes at codon 129 did not result in disease [32, 52, 55, 56, 60, 63]. A recent study by Wang et al., showed that transgenic mice overexpressing human M129- and V129-PrPC are susceptible to in vitro-generated PrPCWD, with elk CWD used as a seed and human V129-PrPC used as a substrate in PMCA. In addition, in this study, PrPCWD could only convert V129-PrPC substrate in vitro, but not M129-PrPC [61].

Squirrel monkeys (Saimiri sciureus) were found to be susceptible to intracerebral (i.c.) and oral CWD infection [6, 7, 36], while cynomolgus macaques (Macaca fascicularis) have conficting results. Race and collaborators have reported that the latter non-human primate model was not susceptible to CWD [50, 51, 53]; while a consortium study including our group reported an atypical phenotype, and positive real-time quaking-induced conversion (RT-QuIC) and PMCA assays in harvested tissues from macaques after challenge with CWD using different routes of inoculation (Czub S, PC, 2017). The human species barrier to CWD infection is presented as strong by most of the studies, yet these findings are still a matter of debate [4]. In the absence of effective management strategies, the prevalence of CWD, the affected geographical areas and the host species range of CWD are increasing, and with that, the potential for human exposure to CWD prions is also increasing. In addition, infectious prions have been found in skeletal muscle [1] and antler velvet [3] in infected cervids, raising yet more concerns about zoonotic transmission of CWD through venison consumption and/or application of cervid products in traditional medicines [4].

In this study, we evaluated the zoonotic potential of CWD using a transgenic mouse model overexpressing human M129-PrPC (tg650 [12]). We inoculated tg650 mice intracerebrally with two deer CWD isolates, Wisc-1 and 116AG [22, 23, 27, 29]. We demonstrate that this transgenic line was susceptible to infection with CWD prions and displayed a distinct leading clinical sign, an atypical PrPSc signature and unusual fecal shedding of infectious prions. Importantly, these prions generated by the human PrP transgenic mice were transmissible upon passage. Our results are the frst evidence of a zoonotic risk of CWD when using one of the most common CWD strains, Wisc-1/CWD1 for infection. We demonstrated in a human transgenic mouse model that the species barrier for transmission of CWD to humans is not absolute. The fact that its signature was not typical raises the questions whether CWD would manifest in humans as a subclinical infection, whether it would arise through direct or indirect transmission including an intermediate host, or a silent to uncovered human-to-human transmission, and whether current detection techniques will be sufcient to unveil its presence.

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Results

To assess and understand the zoonotic potential of CWD, we transmitted CWD prions from deer, without prior adaptation through in vivo or in vitro amplifcation, to tg650 mice overexpressing homozygous human M129-PrPC [12] (humanized mice). We inoculated intracerebrally tg650 mice (n=10 per group) with brain homogenates of CWD-positive white-tailed deer. To investigate potential diferences in the ability of CWD strains to infect tg650 mice, two isolates harboring diferent strains of CWD were used, Wisc-1, a CWD strain derived from a white-tailed deer expressing the cervid wild-type PrP, or 116AG, an isolate from a white-tailed deer harboring a polymorphism at position 116 (A116G) and identifed to contain a mixture of two co-existing strains both distinct from Wisc-1 prions [22, 23, 27, 29]. We also had a group of nine non-infected tg650 age-matched negative controls [623–934 days post-inoculation (dpi)]. The scheme in Supplementary Fig. 1 (online resource) summarizes transmissions and results detailed onwards.

Humanized mice are susceptible to CWD prions

In cervids afected with CWD, the clinical presentation is mainly that of a wasting syndrome. Clinical manifestations such as behavioral changes (e.g., depression, isolation from the herd), excessive salivation, polyuria and teeth grinding are also observed. However, in rodent models of prion disease, including CWD inoculated models, we usually anticipate neurological signs, such as ataxia, gait abnormalities, weakness, rigid tail, and kyphosis, and behavioral changes such as isolation, wasting, irresponsiveness, and weight loss.

We closely monitored tg650 CWD-inoculated mice, and their age-matched non-infected controls, for progressive signs of prion diseases. Starting at 365±30 dpi, we observed that 93.75% of the mice, irrespective of the inoculum, developed myoclonus, as diagnosed by our veterinarian (see Supplementary Video 1, online resource), an unusual clinical manifestation not typically observed in rodent prion models. Clinical signs progressed, with some mice undergoing cycles of weight loss and (re)gain, and lastly drastic weight loss. Eventually, some animals developed typical signs of prion disease, such as rigid tail, kyphosis, hind-limb clasping, ataxia, paralysis, heavy breathing, irresponsiveness, and gait abnormalities (see Supplementary Video 2, and Supplementary Table 1, online resource). Mice were euthanized either at a terminal disease stage or at the experimental endpoint of>900 dpi.

Animals with subtle clinical signs were identifed as those that developed some subtle and/or transient signs that did not progress over the course of the experiment; however, all of these animals had myoclonus. Animals with terminal clinical signs were those with confrmatory prion signs that progressed and reached terminal stage of disease. Based on this standard, of the mice inoculated with Wisc-1 prions 77.7% were clinical, of which, 44.4% progressed with terminal clinical signs, and 33.3% developed subtle clinical signs (Supplementary Table 2, and Supplementary Fig. 2, online resource). Of the 116AG-inoculated mice, 71.5% developed progressive clinical signs, of these, 28.6% showed terminal clinical signs, and 42.9% presented with subtle clinical signs (Supplementary Table 2 and Supplementary Fig. 2, online resource). Age-matched non-infected control mice (n=9) did not exhibit any behavioral or neurological signs and were healthy up to the experimental endpoints between 623 dpi and>900 dpi (Supplementary Table 2, Supplementary Fig. 2, Supplementary Video 3, online resource).

We used RT-QuIC assay, a highly sensitive in vitro conversion technique demonstrated to vie the sensitivity of animal bioassays [62], to detect the presence of PrP amyloid seeding activity in the brains, spinal cords, and spleens of CWD-inoculated tg650 mice.

The RT-QuIC results depicted in Fig. 1a show reactions seeded with brain homogenates and are representative of one assay for each tg650-inoculated mouse with Wisc-1. Each curve represents the average of 8 replicates for each tested dilution (10–1 to 10–6). In addition, to achieve a better sensitivity of detection, we included a substrate replacement step after 25 h reaction time (arrow shown in Fig. 1a), where 90% of the reaction mixture was replaced with fresh assay bufer containing recombinant PrP and the RT-QuIC run was carried on up to 60 h. This step improves sensitivity of detection of low level prion seeding activity in tissues and fuids [15, 16, 40]. Brain homogenates of age-matched non-infected control mice were also tested. For each RT-QuIC run, an age-matched negative control BH was used as internal negative control, and they were consistently negative (Fig. 1a, b, and Supplementary Fig. 3, online resource). Wisc-1 (Fig. 1b) and sCJD brain homogenates (Supplementary Fig. 4a, online resource) were used as positive controls. We considered a dilution to be positive when 50% or more of the replicates turned positive, inconclusive when less than 50% of the replicates were positive, and negative when none of the replicates turned positive.

RT-QuIC results are summarized in a heat map (Fig. 1b). Prion seeding activity was repeatedly detected in 77.7% of the brains of Wisc-1-inoculated mice in at least one of the six tested dilutions (Fig. 1b), while 22.2% (mice #326 and #327) had inconclusive results (Fig. 1b), probably due to very low levels of prion seeding activity at the detection limit in these mice. The RT-QuIC results did not always correlate with the clinical status of the animals at the time of euthanasia. In fact, mouse #327, an animal with terminal disease (Supplementary Table 1 and Supplementary Video 2, online resource) had very poor seeding activity with only one replicate out of eight being positive for two dilutions (10–1 and 10–4) while all other dilutions were strictly negative (Fig. 1). In contrast, mouse #322 had strong positive seeding activity in two dilutions (10–1 and 10–2; Fig. 1) yet the mouse did not develop any prion signs throughout the course of the experiment (Supplementary Table 1, online resource).

Brains of all mice inoculated with the 116AG isolate were negative in RT-QuIC, regardless of the clinical state of the animals (Supplementary Table 1, online resource); however, we have shown previously that this isolate induces slower disease progression, longer survival and lower seeding activity compared to Wisc-1 in cervid PrP transgenic mice [27, 29]. None of the CWD inoculated mice, regardless of the inoculum, had seeding activity in the spinal cord and spleen.

Next, we performed Western blot analysis of brain homogenates digested with PK (200 µg/mL [10, 37]), a gold standard for the diagnosis of prion disease, to determine the presence of PK-resistant PrPSc (PrPres) in the brains of CWD-inoculated tg650 mice. We detected PrPres in the brain of a Wisc-1-inoculated tg650 mouse, #321 (Fig. 2). This mouse that was euthanized at 882 dpi upon reaching the terminal stage of disease, was the frst one to show myoclonus (Supplementary Table 1, online resource) and had the highest levels of seeding activity in RT-QuIC up to a dilution of 10–6 (Fig. 1). This indicates correlation between the amount of seeding activity and PrPres signal detectable in Western blot. Remarkably, the PK-resistant PrPSc core presented as two fragments with estimated molecular weights of 12–13 and 7–8 kDa (Fig. 2). These fragments were detected by two anti-PrP monoclonal antibodies (mAb) that recognize epitopes of the central region of PrP, Sha31 (aa 145–152) and 12F10 (aa 145–155), and by a third mAb binding an N-terminal epitope, 9A2 (aa 102–104). Notably, N-terminal mAb 12B2 (aa 93–97) only detected the 12–13 kDa fragment, indicating an N-terminal cleavage of this atypical PrPSc at this site (Fig. 2). To rule out the possibility of a nonspecifc signal, we performed a Western blot with the same samples mentioned above (Fig. 2) using only a secondary Ab to probe the immunoblot. The secondary Ab alone did not detect any of the PK-resistant fragments (Supplementary Fig. 5a, online resource), thus, validating the specifcity of the truncated PrPres fragments found in the brain of mouse #321 (Fig. 2).

Consistent with the results found in RT-QuIC, mice inoculated with 116AG isolate were all negative for PrPres on Western blot (Supplementary Fig. 5b, online resource). We performed neuropathological analyses to assess spongiosis and abnormal PrP deposition, which are undeniable hallmarks to diagnose prion diseases. First, we analyzed spongiform lesions in the gray matter of Wisc-1-inoculated tg650 mice and their age-matched negative controls. No difference in spongiform degeneration was observed between CWD inoculated animals and negative controls (data not shown). At this stage, CWD-inoculated and non-inoculated tg650 mice were old and vacuolar changes were present equally in their brains due to natural aging process. Next, we performed immunohistochemical analysis (IHC) of the brain tissues from Wisc-1-inoculated tg650 mice to detect disease-associated PrP deposits. Age-matched negative controls were used to set a baseline of normal PrP staining and determine non-disease-associated PrP aggregates. Brain tissues were stained with mAb 12F10 using two diferent staining protocols with either PK digestion or guanidine thiocyanate denaturation (Fig. 3), and we only considered a sample positive if abnormal PrP deposits were detected with both protocols. IHC revealed abnormal PrP deposits mainly located in the thalamus, hypothalamus, and the midbrain/pons areas of one (mouse #328) out of the six Wisc-1-inoculated mice that were tested (Fig. 3 and Supplementary Fig. 6, online resource). PrP deposits showed granular morphology surrounding the cells in these areas. The pericellular staining observed in circumscribed areas of mouse #328 is diferent from the typical PrP-deposits seen in prion diseases, such as synaptic or plaque-like deposits. Mouse #328 was euthanized at 934 dpi with subtle clinical signs (Supplementary Table 1, online resource). It showed strong seeding activity in RT-QuIC (Fig. 1) but was negative for PrPres in Western blot (Fig. 2). As expected, age-matched controls were negative for abnormal PrP deposits (Fig. 3 and Supplementary Fig. 7, online resource). The IHC protocol with PK digestion showed a stronger background compared to the one with guanidine denaturation. To ascertain that the background staining is diferent from the actual abnormal PrP staining observed in the thalamus, hypothalamus and midbrain/pons areas, we have shown in Supplementary Fig. 6 (online resource) all nine studied brain regions of mouse #328. While the background is present equally in all diferent regions, the specifc pericellular PrP staining is present only in the thalamus, hypothalamus and midbrain/pons areas and is absent in all other brain regions (Supplementary Fig. 6, online resource).

To assess infectivity and transmissibility of CWD prions in humanized mice (hCWD), we performed second passage using brain/spinal cord homogenates from mouse #327, the frst mouse euthanized with terminal clinical disease, to bank voles (n=6) and tg650 mice (n=5). The diferent bioassays are still ongoing, but to date, transmission of mouse #327 induced terminal prion disease at 441 dpi in one bank vole (#3054) exhibiting tremor, ataxia, kyphosis, gait abnormalities, and rigid tail (see Supplementary Video 4, online resource). Another bank vole (#3053) died due to malocclusion at 293 dpi, yet it was monitored prior to its death because of clinical signs of transient kyphosis and gait abnormalities (dragging its left hind paw). Brain homogenates of both bank voles tested in RT-QuIC showed positive seeding activity in the brain (Supplementary Fig. 8a and b, online resource). However, none of the bank voles showed PrPres signal in their brain homogenates in Western blot.

Strikingly, second passage in tg650 mice of the brain/ spinal cord homogenate pool resulted to date in terminal prion disease at 504 dpi in one mouse (#3063). This animal exhibited myoclonus at 11 months post-inoculation, followed by rigid tail, rough coat, ataxia and cycles of weight loss and gain. Western blot analysis of PK-digested (200 µg/ mL) brain homogenates revealed atypical PrPres fragments (Fig. 4), resembling those of Wisc-1-inoculated tg650 mouse #321 (Fig. 2) in molecular weights and N-terminal cleavage site. These results demonstrate the presence of transmissible prion infectivity (hCWD) in the CNS of terminally sick tg650 mouse #327, despite the absence of detectable seeding activity in RT-QuIC (Fig. 1), PrPres in Western blot (Fig. 2), and abnormal PrP deposits in IHC (Supplementary Fig. 7, online resource).

CWD inoculated humanized mice shed infectious prions in feces

CWD prions are excreted in feces of infected, preclinical cervids [15, 57, 58]. Therefore, we collected feces from symptomatic and asymptomatic Wisc-1 or 116AG-inoculated tg650 mice, as well as their age-matched controls, between 600 and 750 dpi. We analyzed fecal homogenates by RT-QuIC. We used mouse recombinant PrP (rPrP) as a substrate and, as for the brain homogenates, substrate replacement for enhanced sensitivity [15, 16]. To verify whether fecal contents may contain inhibitors of amyloid formation we performed spiking experiments. We used fecal homogenates from age-matched non-inoculated controls to spike with sCJD brain homogenates as additional positive control (Supplementary Fig. 4b, online resource). Remarkably, 50% of the mice showed positive seeding activity in some replicates and dilutions (Supplementary Fig. 9a, online resource). Wisc-1-inoculated mouse #327 had consistently high levels of seeding activity with 75–100% positive replicates, up to a dilution of 10–3 (Fig. 5). We confrmed these results using human rPrP (Supplementary Fig. 9b, online resource).

To validate the presence of infectious prions in fecal homogenates, we intracerebrally inoculated bank voles (n = 9) and tg650 mice (n = 10) with 10% sonicated fecal homogenates from mouse #327 (summarized in Supplementary Fig. 1, online resource). Fecal homogenate inoculation to tg650 mice caused, so far, prion disease in 50% of the inoculated mice with the bioassay still ongoing. The mice presented with myoclonus at an early stage of the course of the experiment, followed by cycles of weight loss and gain, and fnally ataxia. These mice were euthanized upon reaching terminal stage of the disease, between 534 and 630 dpi. However, analyses of brain homogenates from these mice by Western blot were negative for PK-resistant PrPSc. To date, fecal homogenate inoculation resulted in prion disease in bank voles (Fig. 6a; black line), with varying survival times (198–531 dpi) and with an attack rate of 66.6% (6/9 voles). Most of the euthanized voles presented subtle clinical signs (5/6), with ataxia as a predominant sign and were euthanized because of excessive weight loss. One bank vole (#3430) presented with progressive weight loss, kyphosis, ataxia, gait abnormalities and was euthanized upon reaching terminal disease stage at 241 dpi (see Supplementary Video 5, online resource). In all tested brain homogenates from bank voles inoculated with Wisc-1-tg650 fecal homogenates, seeding activity was detectable by RTQuIC (Fig. 7a–c). In addition to the high levels of seeding activity found in the brain homogenates of bank vole #3430 (Fig. 7c), spinal cord homogenates from this animal also showed strong seeding activity (Fig. 7d).

Next, we performed Western blot analysis of PK-digested (50 µg/mL) brain and spinal cord homogenates from bank vole #3430. We detected a typical three banding patternPrPres signal in both tissues (Fig. 6b and Supplementary Fig. 10a, online resource).

Remarkably, analyses of small intestine and colon homogenates of bank vole #3430 by RT-QuIC revealed positive seeding activity (Fig. 7e, f, respectively). Small intestine homogenates displayed stronger seeding activity up to a dilution of 10–5 compared to colon homogenate, possibly due to the presence of inhibitory components [15] in the colon or generally lower levels of prion seeding activity. However, after PK digestion, none of these tissues was positive for PrPres in Western blot. Spleen homogenates of fecal homogenate-inoculated bank voles were negative in both Western blot and RT-QuIC.

Next, to validate the transmissibility of prions present in bank voles inoculated with Wisc-1-tg650 fecal homogenates, we performed a second passage of brain homogenates from bank vole #3430 into the same host (n=4). Second passage resulted in a complete attack rate (Fig. 6a; purple line), and all inoculated bank voles succumbed to terminal prion disease. The decrease in survival time upon second passage (average of 137±3 dpi; Fig. 6a; purple line) illustrates an adaptation of these prions to their new host. Western blot analyses of samples from second passage showed the presence of a three banding PrPres pattern in the brain and spinal cord homogenates of these animals (Fig. 6b). As a negative control, we also inoculated bank voles with fecal homogenates of tg650 non-inoculated mice. One of the voles was euthanized at 550 dpi to test for seeding activity by RTQuIC, and it was found negative. To date (>600 dpi), the remaining bank voles in this control group are still healthy and not displaying any signs.

Next, we wanted to compare PK-resistant PrPSc biochemical signature in brain homogenates of bank voles inoculated with Wisc-1-tg650 fecal homogenates, Wisc-1 original deer isolate, and Wisc-1 inoculated in bank voles [29] (bvWisc-1; 1st and 2nd passage). Western blot analyses showed that the PrPres signal in brain homogenates of bank voles inoculated with Wisc-1-tg650 fecal homogenates (Fig. 6b, 8a and Supplementary Fig. 10a, online resource) difered from the PrPres signal in brain homogenates of bvWisc-1 (Fig. 8a and Supplementary Fig. 10a, online resource). The unglycosylated PrPres band of bvWisc-1 migrates at an approximate molecular weight of 20 kDa, diferent from that of the Wisc-1 original deer isolate (18–19 kDa; Fig. 8a and [29]). Interestingly, unglycosylated PrPres in brain and spinal cord homogenates from bank vole #3430 inoculated with Wisc-1-tg650 fecal homogenates migrated at 18–19 kDa (Fig. 6b, 8a and Supplementary Fig. 10a, online resource) resembling that of the Wisc-1 original deer isolate (Fig. 8a). When we quantifed the signal of the di-, mono-, and unglycosylated bands (Fig. 8b and Supplementary Fig. 10b, online resource), we found that bvWisc-1 presented with a predominant di-glycosylated band and a non-detectable unglycosylated band, compared to Wisc-1 deer isolate and bank voles inoculated with Wisc-1-tg650 fecal homogenates in 1st and 2nd passage (Fig. 8b and Supplementary Fig. 10b, online resource). The PrPres signal intensity in bank vole #3430 was stronger compared to that of bvWisc-1, considering that PK digestion was performed at diferent concentrations, 25 µg/mL for bvWisc-1 compared to 50 µg/mL for bank vole #3430, and diferent volumes were applied for Western blot analysis, with 20 times higher volume loaded for bvWisc-1 compared to bank vole #3430 (Fig. 8a and Supplementary Fig. 10a, online resource). To further ascertain the diference between bvWisc-1 and prions from bank voles inoculated with Wisc-1-tg650 fecal homogenates, we compared their conformational stability using guanidine hydrochloride (Gdn.HCl) denaturation. The concentration of Gdn.HCl necessary to unfold 50% of the PrPSc ([Gdn. HCl]1/2) of bvWisc-1 prions was signifcantly higher than that of PrPSc of bank voles inoculated with Wisc-1-tg650 fecal homogenates ([2 M] vs [1.25 M], respectively). These results revealed a signifcantly higher conformational stability of bvWisc-1 PrPSc (Fig. 8c). These data demonstrate that humanized tg650 mice inoculated with CWD prions shed prion infectivity in feces able to generate transmissible PrPSc in bank voles distinct from those generated by inoculation of the Wisc-1 deer isolate directly to bank voles.

Discussion

Our fndings strongly suggest that CWD should be regarded as an actual public health risk. Here, we use humanized mice to show that CWD prions can cross the species barrier to humans, and remarkably, infectious prions can be excreted in feces.

Many factors have to be taken into account for prions to be able to cross the species barrier. Notably, the homology between the host PrP primary structure and the donor PrPSc plays a crucial role in species barrier [9, 13, 21, 59]. In addition, the existence of diferent CWD strains and the impact of the Prnp polymorphism, the extensive incubation period, and the atypical clinical presentation should be considered when investigating the risk of CWD. Determining that CWD poses a signifcant risk to human health is of a crucial importance to prevent a public health and economic crisis similar—if not greater—to that of BSE transmission to humans (i.e., vCJD) because CWD not only afects farmed but also free-ranging cervids and therefore cannot be controlled under the same circumstances that BSE in cattle was controlled.

Several studies have evaluated the susceptibility of humans to CWD [41]. Most in vitro studies had found that CWD prions are capable to convert human PrPC, however, either the efciency of the conversion was low or relied on protein modifcations by denaturation [5–7, 35, 47]. RTQuIC assay showed that PrPCWD can seed the conversion of human recombinant PrP, however, PrPBSE did not seed it making the veracity of these results questionable [19]. Transgenic mouse models overexpressing the human prion protein have been extensively used to assess the transmission of various human prions in vivo, thus, they are also used as a model to test the zoonotic potential of prions from other species such as cervids (CWD) [32, 33, 52, 55, 56, 60, 61, 63]. Diferent transgenic lines with diferent polymorphism at residue 129 (M or V), expressing human PrPC at diferent expression levels, and in variable tissues (because of the transgene construct), were used in these studies, that were infected with diferent sources of CWD prions.

CWD transmission to humanized mice was assessed in all these studies by monitoring the clinical signs, examining the brain for neuropathology associated with prion disease, and IHC staining for PrP deposits. Brains were also analyzed by Western blot after PK digestion for detection of PrPres. Wilson and coworkers used an antigen immunoassay, to screen for PrPCWD [63], and Race et al. used RT-QuIC to assess the PrP amyloid formation in the brain of CWD inoculated humanized mice [52]. In three of the in vivo studies [32, 52, 63], clinical signs were observed in a relatively small number of CWD inoculated mice. Race et al. showed positive seeding activity in the brains of very few suspect animals, however, these results were inconsistent, and the authors questioned their signifcance [52]. Prion disease could not be detected in any of the other studies. As RTQuIC assay was not available at the time of other reports [25, 32, 55, 56], they might have missed subclinical manifestations in their CWD-inoculated humanized mice. In addition, except for one study where the mice were kept up to 798 dpi [52], in most of the studies the experiments were terminated between 500 and 600 dpi. In our study, tg650 mice were kept for up to>900 dpi, which is at least+15% of the survival compared to the longest study. This could be a signifcant asset to this line when it comes to human prion diseases with a very prolonged incubation period.

In our study, inconclusive or negative seeding activity observed in 22.2% of Wisc-1-inoculated tg650 mice even with the substrate replacement step, regardless of the fact that mouse #327 was clinically sick (see Supplementary video 2, online resource) could be explained by low levels of prions in the brains of these mice. Nevertheless, prion infectivity was present and transmissible (mouse #327 → #3063), which is the most relevant criterion to demonstrate the presence of prions in case other assays provide inconclusive results. The modifed RT-QuIC protocol with substrate replacement used here allowed us to ensure the availability of rPrP substrate for a longer period of time to enable the detection of low levels of prion seeding activity that would have been missed otherwise. Positive seeding activity observed in the brain of 77.7% of Wisc-1-tg650 inoculated mice was consistent and reproducible, however, one concern was that these results are the product of remaining inoculum as reported by Martin et al. [37], or a combination of both de novo generated PrPCWD in these mice, with regards to our results, and remnant inoculum. Nevertheless, our results are in disfavor of a scenario involving a remnant inoculum alone. In fact, transmission of brain homogenates from knockout mice with remaining sCJD inoculum generated prion disease in tg650 mice that was undistinguishable from that generated by sCJD inoculation of these mice. In our case, transmission of Wisc-1-CWD to tg650 mice resulted in clinical disease, and transmission of hCWD occult prions (mouse #327) that were transmissible upon second passage exposing an atypical PrPres pattern (mouse #3063) similar to that detected in frst passage (mouse #321). The presence of infectious prions shed in feces is one argument in favor of the existence of de novo generated PrPSc in these mice. Another argument is the distinct biochemical signature of PrPSc found in bank voles inoculated with Wisc-1-tg650 fecal homogenates compared to bvWisc-1 prions. In fact, the diferences in the migration profle of the unglycosylated band (Fig. 8a), the glyco-form ratio (Fig. 8b and Supplementary Fig. 10, online resource), and the conformational stability (Fig. 8c), are all strong indicators of distinct prion conformers, and compelling arguments conficting with a possibility of remnant or spilled Wisc-1 inoculum in tg650 mice. This implicates that prions generated following Wisc-1 inoculation in tg650 mice underwent a modifcation governed by the presence of the human PRNP sequence. The recent study by Wang et al. claiming susceptibility of humanized mice to CWD failed to transmit the original elk isolate to the mice, rather, they generated PrPCWD by PMCA using V129 PrPC as substrate [61]. The study showed that CWD prions only converted V129-PrPC but not M129-PrPC, somehow contradicting previous reports demonstrating that CWD also converted M129-PrPC [47].

Our results indicate that if CWD crosses the species-barrier to humans, it is unlikely to resemble the most common forms of human prion diseases with respect to clinical signs, tissue tropism and PrPSc signature. For instance, PrPSc in variable protease-sensitive prionopathy (VPSPr), a sporadic form of human prion disease, and in the genetic form Gerstmann-Sträussler-Scheinker syndrome (GSS) is defned by an atypical PK-resistant PrPSc fragment that is non-glycosylated and truncated at both C- and N-termini, with a molecular weight between 6 and 8 kDa [24, 44–46]. These biochemical features are unique and distinctive from PrPSc (PrP27-30) found in most other human or animal prion disease. The atypical PrPSc signature detected in brain homogenate of tg650 mice #321 (1st passage) and #3063 (2nd passage), and the 7–8 kDa fragment (Figs. 2, 4) are very similar to that of GSS, both in terms of migration profle and the N-terminal cleavage site.

CWD in humans might remain subclinical but with PrPSc deposits in the brain with an unusual morphology that does not resemble the patterns usually seen in different prion diseases (e.g., mouse #328; Fig. 3), clinical with untraceable abnormal PrP (e.g., mouse #327) but still transmissible and uncovered upon subsequent passage (e.g., mouse #3063; Fig. 4), or prions have other reservoirs than the usual ones, hence the presence of infectivity in feces (e.g., mouse #327) suggesting a potential for human-to-human transmission and a real iatrogenic risk that might be unrecognizable. Here, humanized mice inoculated with CWD deer isolates had an atypical onset of the disease with myoclonus (93.75%), before presenting typical clinical signs, generating prions that presented with either atypical biochemical signature (#321 and #3063), shed in feces (#327), or were undetectable by the classical detection methods. The fact that we could not establish a strong correlation between disease manifestation in tg650 mice inoculated with Wisc-1- or 116AG-CWD and the presence of abnormal PrP (Western blot, IHC or RTQuIC) might be explained by the presence of heterogeneous prions in the brains of infected mice with different seeding properties in vitro. Indeed, such heterogeneity and distinct seeding activities and infectivity of abnormal PrP fragments was observed in VPSPr cases [20, 43]. We could not establish a correlation between the presence of PrPSc deposits in mouse #328 and the absence of resistant PrP in Western blot even though prions present in the brain of this animal seeded the conversion of rPrP substrate very well (Fig. 1). Mouse #321 was not available for IHC; therefore, we cannot draw a conclusion about abnormal PrP deposits in the brain of this animal, but we can conclude that there is a correlation between level of prion seeding activity (Fig. 1) and the detection of atypical PrPres fragments (Fig. 2) present in the brain of this animal. We can only speculate that transmission of Wisc-1 to tg650 mice generated prions with characteristics that render them less prone to be unveiled with conventional methods. However, 77.7% of these mice showed prion seeding activity despite the absence of PK-resistant PrPSc for most of them, suggesting that protease-sensitive prions could be involved in these transmissions like it was shown in human prion diseases [54]. Further analyses such as conformation-dependent immunoassay [54] and in vivo sub-passages will be required to resolve these questions.

The finding that infectious PrPSc was shed in fecal material of CWD-infected humanized mice and induced clinical disease, diferent tropism, and typical three banding pattern-PrPres in bank voles that is transmissible upon second passage is highly concerning for public health. The fact that this biochemical signature in bank voles resembles that of the Wisc-1 original deer isolate and is diferent from that of bvWisc-1, in the migration profle and the glyco-form-ratio, is valid evidence that these results are not a product of contamination in our study. If CWD in humans is found to be contagious and transmissible among humans, as it is in cervids [57], the spread of the disease within humans might become endemic. In contrast to bank voles inoculated with fecal homogenates from mouse #327, so far, we could not detect a PK-resistant PrPSc fragment in the brain homogenates of fecal homogenate-inoculated tg650 mice. The presence of PrPres in these mice will allow us to determine if the molecular signature of hCWD prions from the brain (mouse #321 and #3063) vs feces are the same. Previously, Beringue et al. found that extraneural prions, compared to neural prions, helped more to overcome the species barrier to foreign prions, in addition, different strain types emerged from such serial transmission [11]. Our data also suggest that prions found in the periphery may hold higher zoonotic potential than prions found in neural tissues. In fact, upon second passage, 50% of the tg650 mice inoculated with fecal homogenates from mouse #327 had succumbed with terminal disease compared to only 20% of brain/spinal cord homogenates inoculatedtg650 mice suggesting that hCWD prions found in feces transmit disease more efciently. Our results also suggest that epidemiological studies [25] may have missed subclinical and atypical infections that are/might be transmissible, undetected by the gold standard tests, i.e., Western blot, ELISA, and IHC.

Ideally, an oral inoculation of mice with CWD prions would have mimicked best the natural route of exposure to acquired prion diseases like CWD. However, in our case, an oral inoculation would have been impossible considering the lifespan of the rodent models. It took us an extended amount of time, over two years and a half, to have a better idea of the extent of CWD transmission in the tg650 model, even with intracerebral inoculation, usually the fastest way to induce prion disease in a rodent model. Taking this into consideration, our study is the strongest proof-of-principle that CWD might be transmissible to humans. The overall risk for zoonotic transmission of CWD is likely lower than that for BSE; however, rather than predicting the absolute zoonotic risk for CWD, our study indicates the possibility of atypical features in humans. Furthermore, our fndings provide striking insights into how CWD might manifest in humans and the impact it may have on human health. We have used Wisc-1/CWD1, one of the most common CWD strains, notably white-tailed deer prions, which have been shown to be more prone to generate human prions in vitro [47]. This implies a high risk of exposure to this strain, e.g., through consumption or handling of infected carcasses, in contrast to rarer CWD strains, and therefore, an actual risk for human health. Fecal shedding of infectious prions, if it occurs in humans, is particularly concerning because of potential human-to-human transmission and adaptation of hCWD. Overall, our fndings suggest that CWD surveillance in humans should encompass a wider spectrum of tissues/organs tested and include new criteria in the diagnosis of potential patients.

Supplementary Information The online version contains supplementary material available at

https://doi.org/10.1007/s00401-022-02482-9

snip...see full text;

https://link.springer.com/article/10.1007/s00401-022-02482-9

https://link.springer.com/content/pdf/10.1007/s00401-022-02482-9.pdf

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

Our results suggest that CWD might infect humans, although the transmission barrier is likely higher compared to zoonotic transmission of cattle prions. Notably, our data suggest a diferent clinical presentation, prion signature, and tissue tropism, which causes challenges for detection by current diagnostic assays. Furthermore, the presence of infectious prions in feces is concerning because if this occurs in humans, it is a source for human-to-human transmission. These fndings have strong implications for public health and CWD management.

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

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;

***> 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

Research Paper

Cellular prion protein distribution in the vomeronasal organ, parotid, and scent glands of white-tailed deer and mule deer

Anthony Ness, Aradhana Jacob, Kelsey Saboraki, Alicia Otero, Danielle Gushue, Diana Martinez Moreno, Melanie de Peña, Xinli Tang, Judd Aiken, Susan Lingle & Debbie McKenzieORCID Icon show less

Pages 40-57 | Received 03 Feb 2022, Accepted 13 May 2022, Published online: 29 May 2022

Download citation

https://doi.org/10.1080/19336896.2022.2079888

ABSTRACT

Chronic wasting disease (CWD) is a contagious and fatal transmissible spongiform encephalopathy affecting species of the cervidae family. CWD has an expanding geographic range and complex, poorly understood transmission mechanics. CWD is disproportionately prevalent in wild male mule deer and male white-tailed deer. Sex and species influences on CWD prevalence have been hypothesized to be related to animal behaviours that involve deer facial and body exocrine glands. Understanding CWD transmission potential requires a foundational knowledge of the cellular prion protein (PrPC) in glands associated with cervid behaviours. In this study, we characterized the presence and distribution of PrPC in six integumentary and two non-integumentary tissues of hunter-harvested mule deer (Odocoileus hemionus) and white-tailed deer (O. virginianus). We report that white-tailed deer expressed significantly more PrPC than their mule deer in the parotid, metatarsal, and interdigital glands. Females expressed more PrPC than males in the forehead and preorbital glands. The distribution of PrPC within the integumentary exocrine glands of the face and legs were localized to glandular cells, hair follicles, epidermis, and immune cell infiltrates. All tissues examined expressed sufficient quantities of PrPC to serve as possible sites of prion initial infection, propagation, and shedding.

https://www.tandfonline.com/doi/full/10.1080/19336896.2022.2079888

ARS RESEARCH Generation of human chronic wasting disease in transgenic mice

Publication Acceptance Date: 9/8/2021

Research Project: Pathobiology, Genetics, and Detection of Transmissible Spongiform Encephalopathies Location: Virus and Prion Research

Title: Generation of human chronic wasting disease in transgenic mice

Author item WANG, ZERUI - Case Western Reserve University (CWRU) item QIN, KEFENG - University Of Chicago item CAMACHO, MANUEL - Case Western Reserve University (CWRU) item SHEN, PINGPING - Case Western Reserve University (CWRU) item YUAN, JUE - Case Western Reserve University (CWRU) item Greenlee, Justin item CUI, LI - Jilin University item KONG, QINGZHONG - Case Western Reserve University (CWRU) item MASTRIANNI, JAMES - University Of Chicago item ZOU, WEN-QUAN - Case Western Reserve University (CWRU)

Submitted to: Acta Neuropathologica Publication Type: Peer Reviewed Journal Publication Acceptance Date: 9/8/2021 Publication Date: N/A Citation: N/A

Interpretive Summary: Prion diseases are invariably fatal neurologic diseases for which there is no known prevention or cure. Chronic wasting disease (CWD) is the prion disease of deer and elk and is present in farmed and free ranging herds throughout North America. To date there is no clear evidence that the CWD agent could be transmitted to humans. This manuscript describes the use of an in vitro technique, cell-free serial protein misfolding cyclic amplification (sPMCA), to generate a CWD prion that is infectious to transgenic mice expressing the human prion protein. This study provides the first evidence that CWD prions may be able to cause misfolding in the human prion protein. This information will impact medical experts and those involved in making policy for farmed cervids and wildlife.

Technical Abstract: Chronic wasting disease (CWD) is a cervid spongiform encephalopathy or prion disease caused by the infectious prion or PrPSc, a misfolded conformer of cellular prion protein (PrPC). It has rapidly spread in North America and also has been found in Asia and Europe. In contrast to the zoonotic mad cow disease that is the first animal prion disease found transmissible to humans, the transmissibility of CWD to humans remains uncertain although most previous studies have suggested that humans may not be susceptible to CWD. Here we report the generation of an infectious human PrPSc by seeding CWD PrPSc in normal human brain PrPC through the in vitro cell-free serial protein misfolding cyclic amplification (sPMCA). Western blotting confirms that the sPMCA-induced proteinase K-resistant PrPSc is a human form, evidenced by a PrP-specific antibody that recognizes human but not cervid PrP. Remarkably, two lines of humanized transgenic (Tg) mice expressing human PrP-129Val/Val (VV) or -129Met/Met (MM) polymorphism develop prion disease at 233 ± 6 (mean ± SE) days post-inoculation (dpi) and 552 ± 27 dpi, respectively, upon intracerebral inoculation with the sPMCA-generated PrPSc. The brain of diseased Tg mice reveals the electrophoretic profile of PrPSc similar to sporadic Creutzfeldt-Jakob disease (sCJD) MM1 or VV2 subtype but different neuropathological patterns. We believe that our study provides the first evidence that CWD PrPSc is able to convert human PrPC into PrPSc in vitro and the CWD-derived human PrPSc mimics atypical sCJD subtypes in humanized Tg mice.

https://www.ars.usda.gov/research/publications/publication/?seqNo115=382551

''The brain of diseased Tg mice reveals the electrophoretic profile of PrPSc similar to sporadic Creutzfeldt-Jakob disease (sCJD) MM1 or VV2 subtype but different neuropathological patterns.''

''We believe that our study provides the first evidence that CWD PrPSc is able to convert human PrPC into PrPSc in vitro and the CWD-derived human PrPSc mimics atypical sCJD subtypes in humanized Tg mice.''

Published: 26 September 2021

Generation of human chronic wasting disease in transgenic mice

Zerui Wang, Kefeng Qin, Manuel V. Camacho, Ignazio Cali, Jue Yuan, Pingping Shen, Justin Greenlee, Qingzhong Kong, James A. Mastrianni & Wen-Quan Zou

Acta Neuropathologica Communications volume 9, Article number: 158 (2021)

Abstract

Chronic wasting disease (CWD) is a cervid prion disease caused by the accumulation of an infectious misfolded conformer (PrPSc) of cellular prion protein (PrPC). It has been spreading rapidly in North America and also found in Asia and Europe. Although bovine spongiform encephalopathy (i.e. mad cow disease) is the only animal prion disease known to be zoonotic, the transmissibility of CWD to humans remains uncertain. Here we report the generation of the first CWD-derived infectious human PrPSc by elk CWD PrPSc-seeded conversion of PrPC in normal human brain homogenates using in vitro protein misfolding cyclic amplification (PMCA). Western blotting with human PrP selective antibody confirmed that the PMCA-generated protease-resistant PrPSc was derived from the human PrPC substrate. Two lines of humanized transgenic mice expressing human PrP with either Val or Met at the polymorphic codon 129 developed clinical prion disease following intracerebral inoculation with the PMCA-generated CWD-derived human PrPSc. Diseased mice exhibited distinct PrPSc patterns and neuropathological changes in the brain. Our study, using PMCA and animal bioassays, provides the first evidence that CWD PrPSc can cross the species barrier to convert human PrPC into infectious PrPSc that can produce bona fide prion disease when inoculated into humanized transgenic mice.

Snip...

It is worth noting that the annual number of sporadic CJD (sCJD) cases in the USA has increased, with the total number of suspected and confirmed sCJD cases rising from 284 in 2003 to 511 in 2017 (https://www.cdc.gov/prions/cjd/occurrence-transmission.html). The greatly enhanced CJD surveillance and an aging population in the USA certainly contributed to the observed increase in annual sCJD case numbers in recent years, but the possibility cannot be excluded that some of the increased sCJD prevalence is linked to CWD exposure.

In the present study, using serial protein misfolding cyclic amplification (sPMCA) assay we generate PrPSc by seeding CWD prions in normal human brain homogenates. Importantly, we reveal that two lines of humanized Tg mice expressing human PrP-129VV and 129MM develop prion diseases upon intracerebral inoculation of the abnormal PrP generated by sPMCA. We believe that our study provides the first opportunity to dissect the clinical, pathological and biochemical features of the CWD-derived human prion disease in two lines of humanized Tg mice expressing two major human PrP genotypes, respectively.

https://actaneurocomms.biomedcentral.com/articles/10.1186/s40478-021-01262-y

i thought i might share some news about cwd zoonosis that i got, that i cannot share or post to the public yet, i promised for various reasons, one that it will cause a shit storm for sure, but it was something i really already knew from previous studies, but, i was told that ;

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

''As you can imagine, 2 and 5 (especially 5) may raise alarms. The evidence we have for 4 are not as strong or tight as I would like to have. At this point, please do not post any of the points publicly yet, but you can refer to points 1-3 in private discussions and all 5 points when discussing with relevant public officials to highlight the long-term risks of CWD zoonosis.''

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

so, i figure your as about as official as it gets, and i think this science is extremely important for you to know and to converse about with your officials. it's about to burn a whole in my pocket. this is about as close as it will ever get for cwd zoonosis to be proven in my time, this and what Canada Czub et al found with the Macaques, plus an old study from cjd surveillance unit back that showed cjd and a 9% increase in risk from folks that eat venison, i will post all this below for your files Sir. i remember back in the BSE nvCJD days, from when the first BSE case in bovine was confirmed around 1984 maybe 83, i forget the good vets named that screwed it up first, Carol something, but from 83ish to 95 96 when nvCJD was linked to humans from BSE in cattle, so that took 10 to 15 years. hell, at that rate, especially with Texas and cwd zoonsis, hell, i'll be dead before it's official, if ever, so here ya go Sir. there was a grant study on cwd zoonosis that had been going on for some time, i followed it over the years, then the grant date for said study had expired, so, i thought i would write the good Professor about said study i.e. Professor Kong, CWRU et al. i will post the grant study abstract first, and then after that, what reply i got back, about said study that i was told not to post/publish...

CWD ZOONOSIS GRANT FIRST;

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

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 # 1R01NS088604-01A1 Application # 9037884 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 2015-09-30 Budget End 2016-07-31 Support Year 1 Fiscal Year 2015 Total Cost $337,507 Indirect Cost $118,756

snip...

https://grantome.com/grant/NIH/R01-NS088604-01A1#panel-abstract

Professor Kongs reply to me just this month about above grant study that has NOT been published in peer reveiw yet...

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

Here is a brief summary of our findings:

snip...can't post, made a promise...tss

On Sat, Apr 3, 2021 at 12:19 PM Terry Singeltary <flounder9@verizon.net> wrote:

snip...

end...tss

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

CWD ZOONOSIS THE FULL MONTY TO DATE

International Conference on Emerging Diseases, Outbreaks & Case Studies & 16th Annual Meeting on Influenza March 28-29, 2018 | Orlando, USA

Qingzhong Kong

Case Western Reserve University School of Medicine, USA

Zoonotic potential of chronic wasting disease prions from cervids

Chronic wasting disease (CWD) is the prion disease in cervids (mule deer, white-tailed deer, American elk, moose, and reindeer). It has become an epidemic in North America, and it has been detected in the Europe (Norway) since 2016. The widespread CWD and popular hunting and consumption of cervid meat and other products raise serious public health concerns, but questions remain on human susceptibility to CWD prions, especially on the potential difference in zoonotic potential among the various CWD prion strains. We have been working to address this critical question for well over a decade. We used CWD samples from various cervid species to inoculate transgenic mice expressing human or elk prion protein (PrP). We found infectious prions in the spleen or brain in a small fraction of CWD-inoculated transgenic mice expressing human PrP, indicating that humans are not completely resistant to CWD prions; this finding has significant ramifications on the public health impact of CWD prions. The influence of cervid PrP polymorphisms, the prion strain dependence of CWD-to-human transmission barrier, and the characterization of experimental human CWD prions will be discussed.

Speaker Biography Qingzhong Kong has completed his PhD from the University of Massachusetts at Amherst and Post-doctoral studies at Yale University. He is currently an Associate Professor of Pathology, Neurology and Regenerative Medicine. He has published over 50 original research papers in reputable journals (including Science Translational Medicine, JCI, PNAS and Cell Reports) and has been serving as an Editorial Board Member on seven scientific journals. He has multiple research interests, including public health risks of animal prions (CWD of cervids and atypical BSE of cattle), animal modeling of human prion diseases, mechanisms of prion replication and pathogenesis, etiology of sporadic Creutzfeldt-Jacob disease (CJD) in humans, normal cellular PrP in the biology and pathology of multiple brain and peripheral diseases, proteins responsible for the α-cleavage of cellular PrP, as well as gene therapy and DNA vaccination.

qxk2@case.edu

https://www.alliedacademies.org/conference-abstracts-files/zoonotic-potential-of-chronic-wasting-disease-prions-from.pdf

https://prionconference.blogspot.com/2018/02/prion-round-table-conference-2018-may.html

http://prionconference.blogspot.com/

SUNDAY, JULY 25, 2021

North American and Norwegian Chronic Wasting Disease prions exhibit different potential for interspecies transmission and zoonotic risk

''Our data suggest that reindeer and red deer from Norway could be the most transmissible CWD prions to other mammals, whereas North American CWD prions were more prone to generate human prions in vitro.''

https://chronic-wasting-disease.blogspot.com/2021/07/north-american-and-norwegian-chronic.html

MONDAY, JULY 19, 2021

***> U Calgary researchers at work on a vaccine against a fatal infectious disease affecting deer and potentially people

https://chronic-wasting-disease.blogspot.com/2021/07/u-calgary-researchers-at-work-on.html

Prion Conference 2018 Abstracts

BSE aka MAD COW DISEASE, was first discovered in 1984, and it took until 1995 to finally admit that BSE was causing nvCJD, the rest there is history, but that science is still evolving i.e. science now shows that indeed atypical L-type BSE, atypical Nor-98 Scrapie, and typical Scrapie are all zoonosis, zoonotic for humans, there from.

HOW long are we going to wait for Chronic Wasting Disease, CWD TSE Prion of Cervid, and zoonosis, zoonotic tranmission to humans there from?

Studies have shown since 1994 that humans are susceptible to CWD TSE Prion, so, what's the hold up with making CWD a zoonotic zoonosis disease, the iatrogenic transmissions there from is not waiting for someone to make a decision.

Prion Conference 2018 Abstracts

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.

Background

Chronic wasting disease (CWD) is a prion disease of deer and elk that has been identified in freeranging cervids in 23 US states. While there is currently no epidemiological evidence for zoonotic transmission through the consumption of contaminated venison, studies suggest the CWD agent can cross the species barrier in experimental models designed to closely mimic humans. We compared rates of human prion disease in states with and without CWD to examine the possibility of undetermined zoonotic transmission.

Methods

Death records from the National Center for Health Statistics, case records from the National Prion Disease Pathology Surveillance Center, and additional state case reports were combined to create a database of human prion disease cases from 2003-2015. Identification of CWD in each state was determined through reports of positive CWD tests by state wildlife agencies. Age- and race-adjusted mortality rates for human prion disease, excluding cases with known etiology, were determined for four categories of states based on CWD occurrence: highly endemic (>16 counties with CWD identified in free-ranging cervids); moderately endemic (3-10 counties with CWD); low endemic (1-2 counties with CWD); and no CWD states. States were counted as having no CWD until the year CWD was first identified. Analyses stratified by age, sex, and time period were also conducted to focus on subgroups for which zoonotic transmission would be more likely to be detected: cases <55 years old, male sex, and the latter half of the study (2010-2015).

Results

Highly endemic states had a higher rate of prion disease mortality compared to non-CWD states (rate ratio [RR]: 1.12, 95% confidence interval [CI] = 1.01 - 1.23), as did low endemic states (RR: 1.15, 95% CI = 1.04 - 1.27). Moderately endemic states did not have an elevated mortality rate (RR: 1.05, 95% CI = 0.93 - 1.17). In age-stratified analyses, prion disease mortality rates among the <55 year old population were elevated for moderately endemic states (RR: 1.57, 95% CI = 1.10 – 2.24) while mortality rates were elevated among those ≥55 for highly endemic states (RR: 1.13, 95% CI = 1.02 - 1.26) and low endemic states (RR: 1.16, 95% CI = 1.04 - 1.29). In other stratified analyses, prion disease mortality rates for males were only elevated for low endemic states (RR: 1.27, 95% CI = 1.10 - 1.48), and none of the categories of CWD-endemic states had elevated mortality rates for the latter time period (2010-2015).

Conclusions

While higher prion disease mortality rates in certain categories of states with CWD in free-ranging cervids were noted, additional stratified analyses did not reveal markedly elevated rates for potentially sensitive subgroups that would be suggestive of zoonotic transmission. Unknown confounding factors or other biases may explain state-by-state differences in prion disease mortality.

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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.

Prion disease is a fatal progressive neurodegenerative disease due to deposition of an abnormal protease-resistant isoform of prion protein. Typical symptoms include rapidly progressive dementia, myoclonus, visual disturbance and hallucinations. Interestingly, in patients with prion disease, the abnormal protein canould also be found in the peripheral nervous system. Case reports of prion deposition in peripheral nerves have been reported. Peripheral nerve involvement is thought to be uncommon; however, little is known about the exact prevalence and features of peripheral neuropathy in patients with prion disease.

We reviewed autopsy-proven prion cases from the National Prion Disease Pathology Surveillance Center that were diagnosed between September 2016 to March 2017. We collected information regarding prion protein diagnosis, demographics, comorbidities, clinical symptoms, physical exam, neuropathology, molecular subtype, genetics lab, brain MRI, image and EMG reports. Our study included 104 patients. Thirteen (12.5%) patients had either subjective symptoms or objective signs of peripheral neuropathy. Among these 13 patients, 3 had other known potential etiologies of peripheral neuropathy such as vitamin B12 deficiency or prior chemotherapy. Among 10 patients that had no other clear etiology, 3 (30%) had familial CJD. The most common sCJD subtype was MV1-2 (30%), followed by MM1-2 (20%). The Majority of cases wasere male (60%). Half of them had exposure to wild game. The most common subjective symptoms were tingling and/or numbness of distal extremities. The most common objective finding was diminished vibratory sensation in the feet. Half of them had an EMG with the findings ranging from fasciculations to axonal polyneuropathy or demyelinating polyneuropathy.

Our study provides an overview of the pattern of peripheral neuropathy in patients with prion disease. Among patients with peripheral neuropathy symptoms or signs, majority has polyneuropathy. It is important to document the baseline frequency of peripheral neuropathy in prion diseases as these symptoms may become important when conducting surveillance for potential novel zoonotic prion diseases.

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P177 PrP plaques in methionine homozygous Creutzfeldt-Jakob disease patients as a potential marker of iatrogenic transmission

Abrams JY (1), Schonberger LB (1), Cali I (2), Cohen Y (2), Blevins JE (2), Maddox RA (1), Belay ED (1), Appleby BS (2), Cohen ML (2)

Background

Sporadic Creutzfeldt-Jakob disease (CJD) is widely believed to originate from de novo spontaneous conversion of normal prion protein (PrP) to its pathogenic form, but concern remains that some reported sporadic CJD cases may actually be caused by disease transmission via iatrogenic processes. For cases with methionine homozygosity (CJD-MM) at codon 129 of the PRNP gene, recent research has pointed to plaque-like PrP deposition as a potential marker of iatrogenic transmission for a subset of cases. This phenotype is theorized to originate from specific iatrogenic source CJD types that comprise roughly a quarter of known CJD cases.

Methods

We reviewed scientific literature for studies which described PrP plaques among CJD patients with known epidemiological links to iatrogenic transmission (receipt of cadaveric human grown hormone or dura mater), as well as in cases of reported sporadic CJD. The presence and description of plaques, along with CJD classification type and other contextual factors, were used to summarize the current evidence regarding plaques as a potential marker of iatrogenic transmission. In addition, 523 cases of reported sporadic CJD cases in the US from January 2013 through September 2017 were assessed for presence of PrP plaques.

Results

We identified four studies describing 52 total cases of CJD-MM among either dura mater recipients or growth hormone recipients, of which 30 were identified as having PrP plaques. While sporadic cases were not generally described as having plaques, we did identify case reports which described plaques among sporadic MM2 cases as well as case reports of plaques exclusively in white matter among sporadic MM1 cases. Among the 523 reported sporadic CJD cases, 0 of 366 MM1 cases had plaques, 2 of 48 MM2 cases had kuru plaques, and 4 of 109 MM1+2 cases had either kuru plaques or both kuru and florid plaques. Medical chart review of the six reported sporadic CJD cases with plaques did not reveal clinical histories suggestive of potential iatrogenic transmission.

Conclusions

PrP plaques occur much more frequently for iatrogenic CJD-MM cases compared to sporadic CJDMM cases. Plaques may indicate iatrogenic transmission for CJD-MM cases without a type 2 Western blot fragment. The study results suggest the absence of significant misclassifications of iatrogenic CJD as sporadic. To our knowledge, this study is the first to describe grey matter kuru plaques in apparently sporadic CJD-MM patients with a type 2 Western blot fragment.

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P180 Clinico-pathological analysis of human prion diseases in a brain bank series

Ximelis T (1), Aldecoa I (1,2), Molina-Porcel L (1,3), Grau-Rivera O (4), Ferrer I (5), Nos C (6), Gelpi E (1,7), Sánchez-Valle R (1,4)

(1) Neurological Tissue Bank of the Biobanc-Hospital ClÃnic-IDIBAPS, Barcelona, Spain (2) Pathological Service of Hospital ClÃnic de Barcelona, Barcelona, Spain (3) EAIA Trastorns Cognitius, Centre Emili Mira, Parc de Salut Mar, Barcelona, Spain (4) Department of Neurology of Hospital ClÃnic de Barcelona, Barcelona, Spain (5) Institute of Neuropathology, Hospital Universitari de Bellvitge, Hospitalet de Llobregat, Barcelona (6) General subdirectorate of Surveillance and Response to Emergencies in Public Health, Department of Public Health in Catalonia, Barcelona, Spain (7) Institute of Neurology, Medical University of Vienna, Vienna, Austria.

Background and objective:

The Neurological Tissue Bank (NTB) of the Hospital Clínic-Institut d‘Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain is the reference center in Catalonia for the neuropathological study of prion diseases in the region since 2001. The aim of this study is to analyse the characteristics of the confirmed prion diseases registered at the NTB during the last 15 years.

Methods:

We reviewed retrospectively all neuropathologically confirmed cases registered during the period January 2001 to December 2016.

Results:

176 cases (54,3% female, mean age: 67,5 years and age range: 25-86 years) of neuropathological confirmed prion diseases have been studied at the NTB. 152 cases corresponded to sporadic Creutzfeldt-Jakob disease (sCJD), 10 to genetic CJD, 10 to Fatal Familial Insomnia, 2 to GerstmannSträussler-Scheinker disease, and 2 cases to variably protease-sensitive prionopathy (VPSPr). Within sCJD subtypes the MM1 subtype was the most frequent, followed by the VV2 histotype.

Clinical and neuropathological diagnoses agreed in 166 cases (94%). The clinical diagnosis was not accurate in 10 patients with definite prion disease: 1 had a clinical diagnosis of Fronto-temporal dementia (FTD), 1 Niemann-Pick‘s disease, 1 Lewy Body‘s Disease, 2 Alzheimer‘s disease, 1 Cortico-basal syndrome and 2 undetermined dementia. Among patients with VPSPr, 1 had a clinical diagnosis of Amyotrophic lateral sclerosis (ALS) and the other one with FTD.

Concomitant pathologies are frequent in older age groups, mainly AD neuropathological changes were observed in these subjects.

Discussion:

A wide spectrum of human prion diseases have been identified in the NTB being the relative frequencies and main characteristics like other published series. There is a high rate of agreement between clinical and neuropathological diagnoses with prion diseases. These findings show the importance that public health has given to prion diseases during the past 15 years. Continuous surveillance of human prion disease allows identification of new emerging phenotypes. Brain tissue samples from these donors are available to the scientific community. For more information please visit:

http://www.clinicbiobanc.org/banc-teixits-neurologics/mostres/en_index.html

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P192 Prion amplification techniques for the rapid evaluation of surface decontamination procedures

Bruyere-Ostells L (1), Mayran C (1), Belondrade M (1), Boublik Y (2), Haïk S (3), Fournier-Wirth C (1), Nicot S (1), Bougard D (1)

(1) Pathogenesis and control of chronic infections, Etablissement Français du Sang, Inserm, Université de Montpellier, Montpellier, France. (2) Centre de Recherche en Biologie cellulaire de Montpellier, CNRS, Université de Montpellier, Montpellier, France. (3) Inserm U 1127, CNRS UMR 7225, Sorbonne Universités, UPMC Université Paris 06 UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, Paris, France.

Aims:

Transmissible Spongiform Encephalopathies (TSE) or prion diseases are a group of incurable and always fatal neurodegenerative disorders including Creutzfeldt-Jakob diseases (CJD) in humans. These pathologies include sporadic (sCJD), genetic and acquired (variant CJD) forms. By the past, sCJD and vCJD were transmitted by different prion contaminated biological materials to patients resulting in more than 400 iatrogenic cases (iCJD). The atypical nature and the biochemical properties of the infectious agent, formed by abnormal prion protein or PrPTSE, make it particularly resistant to conventional decontamination procedures. In addition, PrPTSE is widely distributed throughout the organism before clinical onset in vCJD and can also be detected in some peripheral tissues in sporadic CJD. Risk of iatrogenic transmission of CJD by contaminated medical device remains thus a concern for healthcare facilities. Bioassay is the gold standard method to evaluate the efficacy of prion decontamination procedures but is time-consuming and expensive. Here, we propose to compare in vitro prion amplification techniques: Protein Misfolding Cyclic Amplification (PMCA) and Real-Time Quaking Induced Conversion (RT-QuIC) for the detection of residual prions on surface after decontamination.

Methods:

Stainless steel wires, by mimicking the surface of surgical instruments, were proposed as a carrier model of prions for inactivation studies. To determine the sensitivity of the two amplification techniques on wires (Surf-PMCA and Surf-QuIC), steel wires were therefore contaminated with serial dilutions of brain homogenates (BH) from a 263k infected hamster and from a patient with sCJD (MM1 subtype). We then compared the different standard decontamination procedures including partially and fully efficient treatments by detecting the residual seeding activity on 263K and sCJD contaminated wires. We completed our study by the evaluation of marketed reagents endorsed for prion decontamination.

Results:

The two amplification techniques can detect minute quantities of PrPTSE adsorbed onto a single wire. 8/8 wires contaminated with a 10-6 dilution of 263k BH and 1/6 with the 10-8 dilution are positive with Surf-PMCA. Similar performances were obtained with Surf-QuIC on 263K: 10/16 wires contaminated with 10-6 dilution and 1/8 wires contaminated with 10-8 dilution are positive. Regarding the human sCJD-MM1 prion, Surf-QuIC allows us to detect 16/16 wires contaminated with 10-6 dilutions and 14/16 with 10-7 . Results obtained after decontamination treatments are very similar between 263K and sCJD prions. Efficiency of marketed treatments to remove prions is lower than expected.

Conclusions:

Surf-PMCA and Surf-QuIC are very sensitive methods for the detection of prions on wires and could be applied to prion decontamination studies for rapid evaluation of new treatments. Sodium hypochlorite is the only product to efficiently remove seeding activity of both 263K and sCJD prions.

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WA2 Oral transmission of CWD into Cynomolgus macaques: signs of atypical disease, prion conversion and infectivity in macaques and bio-assayed transgenic mice

Schatzl HM (1, 2), Hannaoui S (1, 2), Cheng Y-C (1, 2), Gilch S (1, 2), Beekes M (3), SchulzSchaeffer W (4), Stahl-Hennig C (5) and Czub S (2, 6)

(1) University of Calgary, Calgary Prion Research Unit, Calgary, Canada (2) University of Calgary, Faculty of Veterinary Medicine, Calgary, Canada, (3) Robert Koch Institute, Berlin, Germany, (4) University of Homburg/Saar, Homburg, Germany, (5) German Primate Center, Goettingen, Germany, (6) Canadian Food Inspection Agency (CFIA), Lethbridge, Canada.

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 found in spinal cord and brain of 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 preclinical 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.

See also poster P103

***> 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.

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WA16 Monitoring Potential CWD Transmission to Humans

Belay ED

Centers for Disease Control and Prevention (CDC), National Center for Emerging and Zoonotic Infectious Diseases, Atlanta, GA, USA.

The spread of chronic wasting disease (CWD) in animals has raised concerns about increasing human exposure to the CWD agent via hunting and venison consumption, potentially facilitating CWD transmission to humans. Several studies have explored this possibility, including limited epidemiologic studies, in vitro experiments, and laboratory studies using various types of animal models. Most human exposures to the CWD agent in the United States would be expected to occur in association with deer and elk hunting in CWD-endemic areas. The Centers for Disease Control and Prevention (CDC) collaborated with state health departments in Colorado, Wisconsin, and Wyoming to identify persons at risk of CWD exposure and to monitor their vital status over time. Databases were established of persons who hunted in Colorado and Wyoming and those who reported consumption of venison from deer that later tested positive in Wisconsin. Information from the databases is periodically cross-checked with mortality data to determine the vital status and causes of death for deceased persons. Long-term follow-up of these hunters is needed to assess their risk of development of a prion disease linked to CWD exposure.

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P166 Characterization of CJD strain profiles in venison consumers and non-consumers from Alberta and Saskatchewan

Stephanie Booth (1,2), Lise Lamoureux (1), Debra Sorensen (1), Jennifer L. Myskiw (1,2), Megan Klassen (1,2), Michael Coulthart (3), Valerie Sim (4)

(1) Zoonotic Diseases and Special Pathogens, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg (2) Department of Medical Microbiology and Infectious Diseases, University of Manitoba, Winnipeg (3) Canadian CJD Surveillance System, Public Health Agency of Canada, Ottawa (4) Division of Neurology, Department of Medicine Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton.

Chronic wasting disease (CWD) is spreading rapidly through wild cervid populations in the Canadian provinces of Alberta and Saskatchewan. While this has implications for tourism and hunting, there is also concern over possible zoonotic transmission to humans who eat venison from infected deer. Whilst there is no evidence of any human cases of CWD to date, the Canadian CJD Surveillance System (CJDSS) in Canada is staying vigilant. When variant CJD occurred following exposure to BSE, the unique biochemical fingerprint of the pathologic PrP enabled a causal link to be confirmed. However, we cannot be sure what phenotype human CWD prions would present with, or indeed, whether this would be distinct from that see in sporadic CJD. Therefore we are undertaking a systematic analysis of the molecular diversity of CJD cases of individuals who resided in Alberta and Saskatchewan at their time of death comparing venison consumers and non-consumers, using a variety of clinical, imaging, pathological and biochemical markers. Our initial objective is to develop novel biochemical methodologies that will extend the baseline glycoform and genetic polymorphism typing that is already completed by the CJDSS. Firstly, we are reviewing MRI, EEG and pathology information from over 40 cases of CJD to select clinically affected areas for further investigation. Biochemical analysis will include assessment of the levels of protease sensitive and resistant prion protein, glycoform typing using 2D gel electrophoresis, testing seeding capabilities and kinetics of aggregation by quaking-induced conversion, and determining prion oligomer size distributions with asymmetric flow field fractionation with in-line light scattering. Progress and preliminary data will be presented. Ultimately, we intend to further define the relationship between PrP structure and disease phenotype and establish a baseline for the identification of future atypical CJD cases that may arise as a result of exposure to CWD.

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Source Prion Conference 2018 Abstracts

http://transmissiblespongiformencephalopathy.blogspot.com/2018/05/prion-2018-may-22-25-2018-santiago-de.html

http://chronic-wasting-disease.blogspot.com/2018/07/oral-transmission-of-cwd-into.html

http://prionconference.blogspot.com/2018/

Volume 24, Number 8—August 2018 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)

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.

snip...

Discussion Characterization of the transmission properties of CWD and evaluation of their zoonotic potential are important for public health purposes. Given that CWD affects several members of the family Cervidae, it seems reasonable to consider whether the zoonotic potential of CWD prions could be affected by factors such as CWD strain, cervid species, geographic location, and Prnp–PRNP polymorphic variation. We have previously used an in vitro conversion assay (PMCA) to investigate the susceptibility of the human PrP to conversion to its disease-associated form by several animal prion diseases, including CWD (15,16,22). The sensitivity of our molecular model for the detection of zoonotic conversion depends on the combination of 1) the action of proteinase K to degrade the abundant human PrPC that constitutes the substrate while only N terminally truncating any human PrPres produced and 2) the presence of the 3F4 epitope on human but not cervid PrP. In effect, this degree of sensitivity means that any human PrPres formed during the PMCA reaction can be detected down to the limit of Western blot sensitivity. In contrast, if other antibodies that detect both cervid and human PrP are used, such as 6H4, then newly formed human PrPres must be detected as a measurable increase in PrPres over the amount remaining in the reaction product from the cervid seed. Although best known for the efficient amplification of prions in research and diagnostic contexts, the variation of the PMCA method employed in our study is optimized for the definitive detection of zoonotic reaction products of inherently inefficient conversion reactions conducted across species barriers. By using this system, we previously made and reported the novel observation that elk CWD prions could convert human PrPC from human brain and could also convert recombinant human PrPC expressed in transgenic mice and eukaryotic cell cultures (15).

A previous publication suggested that mule deer PrPSc was unable to convert humanized transgenic substrate in PMCA assays (23) and required a further step of in vitro conditioning in deer substrate PMCA before it was able to cross the deer–human molecular barrier (24). However, prions from other species, such as elk (15) and reindeer affected by CWD, appear to be compatible with the human protein in a single round of amplification (as shown in our study). These observations suggest that different deer species affected by CWD could present differing degrees of the olecular compatibility with the normal form of human PrP.

The contribution of the polymorphism at codon 129 of the human PrP gene has been extensively studied and is recognized as a risk factor for Creutzfeldt-Jakob disease (4). In cervids, the equivalent codon corresponds to the position 132 encoding methionine or leucine. This polymorphism in the elk gene has been shown to play an important role in CWD susceptibility (25,26). We have investigated the effect of this cervid Prnp polymorphism on the conversion of the humanized transgenic substrate according to the variation in the equivalent PRNP codon 129 polymorphism. Interestingly, only the homologs methionine homozygous seed–substrate reactions could readily convert the human PrP, whereas the heterozygous elk PrPSc was unable to do so, even though comparable amounts of PrPres were used to seed the reaction. In addition, we observed only low levels of human PrPres formation in the reactions seeded with the homozygous methionine (132 MM) and the heterozygous (132 ML) seeds incubated with the other 2 human polymorphic substrates (129 MV and 129 VV). The presence of the amino acid leucine at position 132 of the elk Prnp gene has been attributed to a lower degree of prion conversion compared with methionine on the basis of experiments in mice made transgenic for these polymorphic variants (26). Considering the differences observed for the amplification of the homozygous human methionine substrate by the 2 polymorphic elk seeds (MM and ML), reappraisal of the susceptibility of human PrPC by the full range of cervid polymorphic variants affected by CWD would be warranted.

In light of the recent identification of the first cases of CWD in Europe in a free-ranging reindeer (R. tarandus) in Norway (2), we also decided to evaluate the in vitro conversion potential of CWD in 2 experimentally infected reindeer (18). Formation of human PrPres was readily detectable after a single round of PMCA, and in all 3 humanized polymorphic substrates (MM, MV, and VV). This finding suggests that CWD prions from reindeer could be more compatible with human PrPC generally and might therefore present a greater risk for zoonosis than, for example, CWD prions from white-tailed deer. A more comprehensive comparison of CWD in the affected species, coupled with the polymorphic variations in the human and deer PRNP–Prnp genes, in vivo and in vitro, will be required before firm conclusions can be drawn. Analysis of the Prnp sequence of the CWD reindeer in Norway was reported to be identical to the specimens used in our study (2). This finding raises the possibility of a direct comparison of zoonotic potential between CWD acquired in the wild and that produced in a controlled laboratory setting. (Table).

The prion hypothesis proposes that direct molecular interaction between PrPSc and PrPC is necessary for conversion and prion replication. Accordingly, polymorphic variants of the PrP of host and agent might play a role in determining compatibility and potential zoonotic risk. In this study, we have examined the capacity of the human PrPC to support in vitro conversion by elk, white-tailed deer, and reindeer CWD PrPSc. Our data confirm that elk CWD prions can convert the human PrPC, at least in vitro, and show that the homologous PRNP polymorphisms at codon 129 and 132 in humans and cervids affect conversion efficiency. Other species affected by CWD, particularly caribou or reindeer, also seem able to convert the human PrP. It will be important to determine whether other polymorphic variants found in other CWD-affected Cervidae or perhaps other factors (17) exert similar effects on the ability to convert human PrP and thus affect their zoonotic potential.

Dr. Barria is a research scientist working at the National CJD Research and Surveillance Unit, University of Edinburgh. His research has focused on understanding the molecular basis of a group of fatal neurologic disorders called prion diseases.

Acknowledgments We thank Aru Balachandran for originally providing cervid brain tissues, Abigail Diack and Jean Manson for providing mouse brain tissue, and James Ironside for his critical reading of the manuscript at an early stage.

This report is independent research commissioned and funded by the United Kingdom’s Department of Health Policy Research Programme and the Government of Scotland. The views expressed in this publication are those of the authors and not necessarily those of the Department of Health or the Government of Scotland.

Author contributions: The study was conceived and designed by M.A.B. and M.W.H. The experiments were conducted by M.A.B. and A.L. Chronic wasting disease brain specimens were provided by G.M. The manuscript was written by M.A.B. and M.W.H. All authors contributed to the editing and revision of the manuscript.

https://wwwnc.cdc.gov/eid/article/24/8/16-1888_article

https://www.ed.ac.uk/clinical-brain-sciences/news/news-jul-dec-2018/cwd-prions-human-conversion

Prion 2017 Conference Abstracts

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 ABSTRACTS REFERENCE

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.

https://efsa.onlinelibrary.wiley.com/doi/full/10.2903/j.efsa.2018.5132

SATURDAY, FEBRUARY 23, 2019

Chronic Wasting Disease CWD TSE Prion and THE FEAST 2003 CDC an updated review of the science 2019

https://chronic-wasting-disease.blogspot.com/2019/02/chronic-wasting-disease-cwd-tse-prion.html

TUESDAY, NOVEMBER 04, 2014

Six-year follow-up of a point-source exposure to CWD contaminated venison in an Upstate New York community: risk behaviours and health outcomes 2005–2011

Authors, though, acknowledged the study was limited in geography and sample size and so it couldn't draw a conclusion about the risk to humans. They recommended more study. Dr. Ermias Belay was the report's principal author but he said New York and Oneida County officials are following the proper course by not launching a study. "There's really nothing to monitor presently. No one's sick," Belay said, noting the disease's incubation period in deer and elk is measured in years. "

http://chronic-wasting-disease.blogspot.com/2014/11/six-year-follow-up-of-point-source.html

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

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

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.

sporadic, spontaneous CJD, 85%+ of all human TSE, did not just happen. never in scientific literature has this been proven.

if one looks up the word sporadic or spontaneous at pubmed, you will get a laundry list of disease that are classified in such a way;

sporadic = 54,983 hits https://www.ncbi.nlm.nih.gov/pubmed/?term=sporadic

spontaneous = 325,650 hits https://www.ncbi.nlm.nih.gov/pubmed/?term=spontaneous

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 $$$ ***

> 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

CWD TSE PRION AND ZOONOTIC, ZOONOSIS, POTENTIAL

Subject: Re: DEER SPONGIFORM ENCEPHALOPATHY SURVEY & HOUND STUDY

Date: Fri, 18 Oct 2002 23:12:22 +0100

From: Steve Dealler

Reply-To: Bovine Spongiform Encephalopathy Organization: Netscape Online member

To: BSE-L@ References:

Dear Terry,

An excellent piece of review as this literature is desperately difficult to get back from Government sites.

What happened with the deer was that an association between deer meat eating and sporadic CJD was found in about 1993. The evidence was not great but did not disappear after several years of asking CJD cases what they had eaten. I think that the work into deer disease largely stopped because it was not helpful to the UK industry...and no specific cases were reported. Well, if you dont look adequately like they are in USA currenly then you wont find any!

Steve Dealler ===============

https://caninespongiformencephalopathy.blogspot.com/2010/03/canine-spongiform-encephalopathy-aka.html

''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).''

CREUTZFELDT JAKOB DISEASE SURVEILLANCE IN THE UNITED KINGDOM THIRD ANNUAL REPORT AUGUST 1994

Consumption of venison and veal was much less widespread among both cases and controls. For both of these meats there was evidence of a trend with increasing frequency of consumption being associated with increasing risk of CJD. (not nvCJD, but sporadic CJD...tss) These associations were largely unchanged when attention was restricted to pairs with data obtained from relatives. ...

Table 9 presents the results of an analysis of these data.

There is STRONG evidence of an association between ‘’regular’’ veal eating and risk of CJD (p = .0.01).

Individuals reported to eat veal on average at least once a year appear to be at 13 TIMES THE RISK of individuals who have never eaten veal.

There is, however, a very wide confidence interval around this estimate. There is no strong evidence that eating veal less than once per year is associated with increased risk of CJD (p = 0.51).

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 ;

http://web.archive.org/web/20090506050043/http://www.bseinquiry.gov.uk/files/yb/1994/08/00004001.pdf

http://web.archive.org/web/20090506050007/http://www.bseinquiry.gov.uk/files/yb/1994/10/00003001.pdf

http://web.archive.org/web/20090506050244/http://www.bseinquiry.gov.uk/files/yb/1994/07/00001001.pdf

Stephen Dealler is a consultant medical microbiologist deal@airtime.co.uk

BSE Inquiry Steve Dealler

Management In Confidence

BSE: Private Submission of Bovine Brain Dealler

snip...see full text;

MONDAY, FEBRUARY 25, 2019

***> MAD DOGS AND ENGLISHMEN BSE, SCRAPIE, CWD, CJD, TSE PRION A REVIEW 2019

https://bseinquiry.blogspot.com/2019/02/mad-dogs-and-englishmen-bse-scrapie-cwd.html

***> ''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).''

***> In conclusion, sensory symptoms and loss of reflexes in Gerstmann-Sträussler-Scheinker syndrome can be explained by neuropathological changes in the spinal cord. We conclude that the sensory symptoms and loss of lower limb reflexes in Gerstmann-Sträussler-Scheinker syndrome is due to pathology in the caudal spinal cord. <***

***> The clinical and pathological presentation in macaques was mostly atypical, with a strong emphasis on spinal cord pathology.<***

***> 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. <***

***> 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.<***

***> 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) <***

https://familialcjdtseprion.blogspot.com/2019/02/cwd-gss-tse-prion-spinal-cord-confucius.html

***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.***

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.

https://www.nature.com/articles/srep11573

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

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

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

GAME FARM INDUSTRY WANTS TO COVER UP FINDINGS OF INCREASE RISK TO CJD FROM CERVID

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 regarding 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

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 emphasized by the finding that some strains of scrapie produce lesions identical to the once which characterize 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 scrapie problem urgent if the sheep industry is not to suffer grievously.

snip...

76/10.12/4.6

http://web.archive.org/web/20010305223125/www.bseinquiry.gov.uk/files/yb/1976/10/12004001.pdf

IN CONFIDENCE

SCRAPIE TRANSMISSION TO CHIMPANZEES

IN CONFIDENCE

reference...

RB3.20

TRANSMISSION TO CHIMPANZEES

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, ilp 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.

6. 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.

R. Bradley

23 September 1990

CVO (+Mr Wells' comments)

Dr T W A Little

Dr B J Shreeve

90/9.23/1.1.

http://web.archive.org/web/20090506041740/http://www.bseinquiry.gov.uk/files/yb/1990/09/23001001.pdf

IN CONFIDENCE CHIMPANZEES

CODE 18-77 Reference RB3.46

Some further information that may assist in decision making has been gained by discussion with Dr Rosalind Ridley.

She says that careful study of Gajdusek's work shows no increased susceptibility of chimpanzees over New World Monkeys such as Squirrel Monkeys. She does not think it would tell you anything about the susceptibility to man. Also Gajdusek did not, she believes, challenge chimpanzees with scrapie as severely as we did pigs and we know little of that source of scrapie. Comparisons would be difficult. She also would not expect the Home Office to sanction such experiments here unless there was a very clear and important objective that would be important for human health protection. She doubted such a case could be made. If this is the case she thought it would be unethical to do an experiment abroad because we could not do it in our own country.

Retrospectively she feels they should have put up more marmosets than they did. They all remain healthy. They would normally regard the transmission as negative if no disease resulted in five years.

We are not being asked for a decision but I think that before we made one we should gain as much knowledge as we can. If we decided to proceed we would have to bear any criticisms for many years if there was an adverse view by scientists or media. This should not be undertaken lightly. There is already some adverse comment here, I gather, on the pig experiment though that will subside.

The Gibbs' (as' distinct from Schellekers') study is somewhat different. We are merely supplying material for comparative studies in a laboratory with the greatest experience of human SEs in the world and it has been sanctioned by USDA (though we do not know for certain yet if chimpanzees specifically will be used). This would keep it at a lower profile than if we conducted such an experiment in the UK or Europe.

I consider we must have very powerful and defendable objectives to go beyond Gibbs' proposed experiments and should not initiate others just because an offer has been made.

Scientists have a responsibility to seek other methods of investigative research other than animal experimentation. At present no objective has convinced me we need to do research using Chimpanzees - a species in need of protection. Resisting such proposals would enable us to communicate that information to the scientist and the public should the need arise. A line would have been drawn.

CVO cc Dr T Dr B W A Little Dr B J Shreeve

R Bradley

26 September 1990

90/9.26/3.2

http://web.archive.org/web/20090506041605/http://www.bseinquiry.gov.uk/files/yb/1990/09/26003001.pdf

this is tse prion political theater here, i.e. what i call TSE PRION POKER...tss

http://web.archive.org/web/20031028205208/www.bseinquiry.gov.uk/files/yb/1990/08/28002001.pdf

http://web.archive.org/web/20030822170317/www.bseinquiry.gov.uk/files/yb/1990/11/01005001.pdf

3. Prof. A. Robertson gave a brief account of BSE. The US approach was to accord it a very low profile indeed. Dr. A Thiermann showed the picture in the ''Independent'' with cattle being incinerated and thought this was a fanatical incident to be avoided in the US at all costs.

snip...

PAGE 26

Transmission Studies

The occurrence of CWD must be viewed against the contest of the locations in which it occurred. It was an incidental and unwelcome complication of the respective wildlife research programmes. Despite its subsequent recognition as a new disease of cervids, therefore justifying direct investigation, no specific research funding was forthcoming. The USDA viewed it as a wildlife problem and consequently not their province! ...page 26.

snip...see;

IN CONFIDENCE

PERCEPTIONS OF UNCONVENTIONAL SLOW VIRUS DISEASE OF ANIMALS IN THE USA

GAH WELLS

REPORT OF A VISIT TO THE USA

APRIL-MAY 1989

http://web.archive.org/web/20090506002237/http://www.bseinquiry.gov.uk/files/mb/m11b/tab01.pdf

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...

https://web.archive.org/web/20090506041740/http://www.bseinquiry.gov.uk/files/yb/1990/09/23001001.pdf

MONDAY, FEBRUARY 25, 2019

***> MAD DOGS AND ENGLISHMEN BSE, SCRAPIE, CWD, CJD, TSE PRION A REVIEW 2019

https://bseinquiry.blogspot.com/2019/02/mad-dogs-and-englishmen-bse-scrapie-cwd.html

Tuesday, May 31, 2022

89th General Session of the World Assembly of OIE Delegates image for WOAH General Summit 2022 Chronic Wasting Disease CWD TSE Prion Discussions and Concerns

https://woahoie.blogspot.com/2022/05/89th-general-session-of-world-assembly.html

THURSDAY, MARCH 31, 2022

EFSA ONE Conference 2022 Chronic Wasting Disease CWD TSE PrP of Cervid and Zoonosis Zoonotic Transmission Singeltary Submission

https://efsaopinionbseanimalprotein.blogspot.com/2022/03/efsa-one-conference-2022-chronic.html

Control of Chronic Wasting Disease OMB Control Number: 0579-0189 APHIS-2021-0004 Singeltary Submission

https://www.regulations.gov/comment/APHIS-2021-0004-0002

https://downloads.regulations.gov/APHIS-2021-0004-0002/attachment_1.pdf

Docket No. APHIS-2018-0011 Chronic Wasting Disease Herd Certification

https://www.regulations.gov/document/APHIS-2018-0011-0003

https://downloads.regulations.gov/APHIS-2018-0011-0003/attachment_1.pdf

Friendly fire, pass it forward, they call it iatrogenic cjd, or what i call 'tse prion poker', are you all in $$$

all iatrogenic cjd is, is sporadic cjd, before the iatrogenic event is discovered, traced back, proven, documented, put into the academic domain, and then finally the public domain, this very seldom happens, thus problem solved, it's all sporadic cjd...

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

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]

https://www.ncbi.nlm.nih.gov/pubmed/8006664?dopt=Abstract

ENVIRONMENT FACTORS FOR THE TRANSMISSION OF CWD TSE PRP

Sensitive detection of chronic wasting disease prions recovered from environmentally relevant surfaces

Environment International

Available online 13 June 2022, 107347

Environment International

Sensitive detection of chronic wasting disease prions recovered from environmentally relevant surfaces

Qi Yuana Gag e Rowdenb Tiffany M.Wolfc Marc D.Schwabenlanderb Peter A.LarsenbShannon L.Bartelt-Huntd Jason C.Bartza

a Department of Medical Microbiology and Immunology, Creighton University, Omaha, Nebraska, 68178, United States of America

b Department of Veterinary and Biomedical Sciences, University of Minnesota, Saint Paul, MN, 55108, United States of America

c Department of Veterinary Population Medicine, University of Minnesota, Saint Paul, MN, 55108, United States of America

d Department of Civil and Environmental Engineering, Peter Kiewit Institute, University of Nebraska-Lincoln, Omaha, Nebraska, 68182, United States of America

Received 26 April 2022, Revised 8 June 2022, Accepted 9 June 2022, Available online 13 June 2022.

https://doi.org/10.1016/j.envint.2022.107347

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Under a Creative Commons license Open access

Highlights • An innovative method for prion recovery from swabs was developed.

• Recovery of prions decreased as swab-drying time was increased.

• Recovery of CWD prions from stainless steel and glass was approximately 30%.

• RT-QuIC enhanced CWD prion detection by 4 orders of magnitude.

• Surface-recovered CWD prion was sufficient for efficient RT-QuIC detection.

Abstract

Chronic wasting disease (CWD) has been identified in 30 states in the United States, four provinces in Canada, and recently emerged in Scandinavia. The association of CWD prions with environmental materials such as soil, plants, and surfaces may enhance the persistence of CWD prion infectivity in the environment exacerbating disease transmission. Identifying and quantifying CWD prions in the environment is significant for prion monitoring and disease transmission control. A systematic method for CWD prion quantification from associated environmental materials, however, does not exist. In this study, we developed an innovative method for extracting prions from swabs and recovering CWD prions swabbed from different types of surfaces including glass, stainless steel, and wood. We found that samples dried on swabs were unfavorable for prion extraction, with the greatest prion recovery from wet swabs. Using this swabbing technique, the recovery of CWD prions dried to glass or stainless steel was approximately 30% in most cases, whereas that from wood was undetectable by conventional prion immunodetection techniques. Real-time quake-induced conversion (RT-QuIC) analysis of these same samples resulted in an increase of the detection limit of CWD prions from stainless steel by 4 orders of magnitude. More importantly, the RT-QuIC detection of CWD prions recovered from stainless steel surfaces using this method was similar to the original CWD prion load applied to the surface. This combined surface swabbing and RT-QuIC detection method provides an ultrasensitive means for prion detection across many settings and applications.

snip...

5. Conclusions

Chronic wasting disease is spreading in North America and it is hypothesized that in CWD-endemic areas environmental persistence of CWD prions can exacerbate disease transmission. The development of a sensitive CWD prion detection method from environmentally relevant surfaces is significant for monitoring, risk assessment, and control of CWD. In this study, we developed a novel swab-extraction procedure for field deployable sampling of CWD prions from stainless steel, glass, and wood. We found that extended swab-drying was unfavorable for extraction, indicating that hydrated storage of swabs after sampling aided in prion recovery. Recoverable CWD prions from stainless steel and glass was approximately 30%, which was greater than from wood. RT-QuIC analysis of the swab extracts resulted in an increase of the detection limit of CWD prions from stainless steel by 4 orders of magnitude compared to conventional immunodetection techniques. More importantly, the RT-QuIC detection of CWD prions recovered from stainless steel surfaces using this developed method was similar to the original CWD prion load without surface contact. This method of prion sampling and recovery, in combination with ultrasensitive detection methods, allows for prion detection from contaminated environmental surfaces.

https://www.sciencedirect.com/science/article/pii/S0160412022002744?via%3Dihub

TUESDAY, MAY 11, 2021

A Unique Presentation of Creutzfeldt-Jakob Disease in a Patient Consuming Deer Antler Velvet

Case Reports

A Unique Presentation of Creutzfeldt-Jakob Disease in a Patient Consuming Deer Antler Velvet

*Joseph Wiedemer, *Yanely Sanchez Ceja, An Cao and Ibrahim Mustafa Department of Neurology, Wright State University Boonshoft School of Medicine, USA Article history

Received: 17-02-2021 Revised: 08-03-2021 Accepted: 13-03-2021

Corresponding Author: Joseph Wiedemer Department of Neurology, Wright State University Boonshoft School of Medicine, USA

Email: Wiedemer.2@wright.edu

*These authors contributed equally to this work and are considered to be co-first authors

Abstract: Creutzfeldt-Jakob Disease (CJD) is a rare rapidly progressive neurodegenerative prion disorder that is usually sporadic but may also be acquired from exposure to infected sources, classically via infections of bovine or human etiology. Cervid transmission of CJD is of particular concern in North America given the rapid spread of Chronic Wasting Disease (CWD)- the Cervid version of CJD. We present a 61-year-old male patient admitted to our service with a one month history of progressive confusion and gait instability, which led to an initial suspicion of Corticobasal Syndrome (CBS) with unusually rapid progression. CJD was also suspected upon learning that the patient began taking deer antler velvet and bovine colostrum supplements roughly two months prior. The diagnosis of CJD was subsequently confirmed by MRI and RT-QuIC CSF assay. Providers should consider Creutzfeldt-Jakob Disease in the differential diagnosis of a patient with cervid exposure and/or in patients with a presentation resembling corticobasal degeneration, especially if symptom onset is rapid. Although it is unclear how this patient acquired CJD, the potential for prion transmission from cervids to humans should be further investigated by the academic community with considerable urgency.

''We believe that our patient’s case of CJD is highly suspicious for cervid etiology given the circumstances of the case as well as the strong evidence of plausibility reported in published literature. This is the first known case of CJD in a patient who had consumed deer antler velvet. Despite the confirmed diagnosis of CJD, a causal relationship between the patient’s disease and his consumption of deer antler velvet cannot be definitively concluded.''

https://thescipub.com/pdf/ajidsp.2021.43.48.pdf

https://creutzfeldt-jakob-disease.blogspot.com/2021/05/a-unique-presentation-of-creutzfeldt.html

Singeltary submission to the BSE Inquiry on CJD and Nutritional Supplements 1998

ABOUT that deer antler spray and CWD TSE PRION...

I have been screaming this since my neighbors mom died from cjd, and she had been taking a supplement that contained bovine brain, bovine eyeball, and other SRMs specified risk materials, the most high risk for mad cow disease.

just saying...

I made a submission to the BSE Inquiry long ago during the BSE Inquiry days, and they seemed pretty interested.

Sender: "Patricia Cantos"

To: "Terry S Singeltary Sr. (E-mail)"

Subject: Your submission to the Inquiry

Date: Fri, 3 Jul 1998 10:10:05 +0100

3 July 1998

Mr Terry S Singeltary Sr.

E-Mail: Flounder at wt.net

Ref: E2979

Dear Mr Singeltary,

Thank you for your E-mail message of the 30th of June 1998 providing the Inquiry with your further comments.

Thank you for offering to provide the Inquiry with any test results on the nutritional supplements your mother was taking before she died.

As requested I am sending you our general Information Pack and a copy of the Chairman's letter. Please contact me if your system cannot read the attachments.

Regarding your question, the Inquiry is looking into many aspects of the scientific evidence on BSE and nvCJD. I would refer you to the transcripts of evidence we have already heard which are found on our internet site at ;

http://www.bse.org.uk.

Could you please provide the Inquiry with a copy of the press article you refer to in your e-mail? If not an approximate date for the article so that we can locate it?

In the meantime, thank you for you comments. Please do not hesitate to contact me on...

snip...end...tss

everyone I tell this too gets it screwed up...MY MOTHER WAS NOT TAKING THOSE SUPPLEMENTS IPLEX (that I ever knew of). this was my neighbors mother that died exactly one year _previously_ and to the day of sporadic CJD that was diagnosed as Alzheimer’s at first. my mother died exactly a year later from the Heidenhain Variant of Creutzfeldt Jakob Disease hvCJD, and exceedingly rare strains of the ever growing sporadic CJD’s. _both_ cases confirmed. ...kind regards, terry

TSEs i.e. mad cow disease's BSE/BASE and NUTRITIONAL SUPPLEMENTS

IPLEX, mad by standard process;

vacuum dried bovine BRAIN, bone meal, bovine EYE, veal Bone, bovine liver powder, bovine adrenal, vacuum dried bovine kidney, and vacuum dried porcine stomach.

also;

what about potential mad cow candy bars ?

see their potential mad cow candy bar list too...

THESE are just a few of MANY of just this ONE COMPANY...TSS

DEPARTMENT OF HEALTH AND HUMAN SERVICES

FOOD AND DRUG ADMINISTRATION CENTER FOR BIOLOGICS EVALUATION AND RESEARCH

TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHIES ADVISORY COMMITTEE

Friday, January 19, 2001 snip...

17 But I think that we could exhibit some quite

18 reasonable concern about blood donors who are taking dietary

19 supplements that contain a certain amount of unspecified-

20 origin brain, brain-related, brain and pituitary material.

21 If they have done this for more than a sniff or something

22 like that, then, perhaps, they should be deferred as blood

23 donors.

24 That is probably worse than spending six months in

25 the U.K.

1/19/01

3681t2.rtf(845) page 501

http://www.fda.gov/ohrms/dockets/ac/cber01.htm

see new url link;

http://web.archive.org/web/20090118060719/http://www.fda.gov/ohrms/dockets/ac/cber01.htm

http://www.fda.gov/ohrms/dockets/dailys/03/Mar03/031403/96N-0417-EC-2.htm

see new url link;

http://web.archive.org/web/20090711132201/http://www.fda.gov/ohrms/dockets/dailys/03/Mar03/031403/96N-0417-EC-2.htm

http://www.fda.gov/ohrms/dockets/ac/01/slides/3681s2_07.pdf

see new url link

http://web.archive.org/web/20060520110922/http://www.fda.gov/ohrms/dockets/ac/01/slides/3681s2_07.pdf

see full text ;

http://chronic-wasting-disease.blogspot.com/2009/03/chronic-wasting-disease-prions-in-elk.html

My neighbors Mom also died from CJD.

She had been taking a nutritional supplement which contained the following;

vacuum dried bovine BRAIN, bone meal, bovine EYE, veal bone, bovine liver
powder, bovine adrenal, vacuum dried bovine kidney, and vacuum dried
porcine stomach. As I said, this woman taking these nutritional
supplements, died from CJD.

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

https://doi.org/10.1136/bmj.319.7220.1312b

Singeltary Submission recorded here;

https://www.bmj.com/rapid-response/2011/10/28/re-vcjd-usa-bse-us

THURSDAY, APRIL 21, 2022

Transmission of Cervid Prions to Humanized Mice Demonstrates the Zoonotic Potential of CWD

https://chronic-wasting-disease.blogspot.com/2022/04/transmission-of-cervid-prions-to_21.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

Tuesday, June 28, 2022

Subclinical infection occurs frequently following low dose exposure to prions by blood transfusion

https://bloodprp.blogspot.com/2022/06/subclinical-infection-occurs-frequently.html

Thursday, October 28, 2021

Chronic Wasting Disease (CWD) TSE Prion Zoonosis, friendly fire, iatrogenic transmission, blood products, sporadic CJD, what if?

https://itseprion.blogspot.com/2021/10/chronic-wasting-disease-cwd-tse-prion.html

vpspr, sgss, sffi, TSE, an iatrogenic by-product of gss, ffi, familial type prion disease, what if ???

Greetings Friends, Neighbors, and Colleagues,

https://familialcjdtseprion.blogspot.com/2019/02/cwd-gss-tse-prion-spinal-cord-confucius.html

http://transmissiblespongiformencephalopathy.blogspot.com/2014/01/vpspr-sgss-sffi-tse-iatrogenic-by.html

Thursday, July 29, 2021

TSE PRION OCCUPATIONAL EXPOSURE VIA ANIMAL OR HUMAN, iatrogenic transmission, nvCJD or sCJD, what if?

https://itseprion.blogspot.com/2021/07/tse-prion-occupational-exposure-via.html

TUESDAY, MAY 10, 2022

Concordance of CSF RT-QuIC across the European Creutzfeldt-Jakob Disease surveillance network

https://creutzfeldt-jakob-disease.blogspot.com/2022/05/concordance-of-csf-rt-quic-across.html

MONDAY, JANUARY 31, 2022

Validation of Revised International Creutzfeldt-Jakob Disease Surveillance Network Diagnostic Criteria for Sporadic Creutzfeldt-Jakob Disease Singeltary Comment Submission

https://creutzfeldt-jakob-disease.blogspot.com/2022/01/validation-of-revised-international.html

Friday, March 11, 2022

Prevalence of Surgical Procedures at Symptomatic Onset of Prion Disease

https://itseprion.blogspot.com/2022/03/prevalence-of-surgical-procedures-at.html

WEDNESDAY, FEBRUARY 02, 2022

Understanding the nature of PrP found in Appendix tissues in the UK population

https://vcjd.blogspot.com/2022/02/understanding-nature-of-prp-found-in.html

FRIDAY, DECEMBER 24, 2021

***> Creutzfeldt Jakob Disease CJD TSE Prion Update December 25, 2021 <***

https://creutzfeldt-jakob-disease.blogspot.com/2021/12/creutzfeldt-jakob-disease-cjd-tse-prion.html

TUESDAY, OCTOBER 26, 2021

Sporadic Creutzfeldt-Jakob Disease in a Very Young Person Singeltary Reply 2021