Sunday, November 11, 2012
Susceptibilities of Nonhuman Primates to Chronic Wasting Disease
Brent Race1 , Kimberly D. Meade-White1, Michael W. Miller, Kent D. Barbian, Richard Rubenstein, Giuseppe LaFauci, Larisa Cervenakova, Cynthia Favara, Donald Gardner, Dan Long, Michael Parnell, James Striebel, Suzette A. Priola, Anne Ward, Elizabeth S. Williams2, Richard Race3, and Bruce Chesebro3
Author affiliations: Rocky Mountain Laboratories, Hamilton, Montana, USA (B. Race, K.D. Meade-White, K.D. Barbian, C. Favara, D. Gardner, D. Long, M. Parnell, J. Striebel, S.A. Priola, A. Ward, R. Race, B. Chesebro); Colorado Division of Wildlife, Fort Collins, Colorado, USA (M.W. Miller); State University of New York Downstate Medical Center, Brooklyn, New York, USA (R. Rubenstein); New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York, USA (G. LaFauci); American Red Cross, Rockville, Maryland, USA (L. Cervenakova); University of Wyoming, Laramie, Wyoming, USA (E.S. Williams)
Chronic wasting disease (CWD) is a transmissible spongiform encephalopathy, or prion disease, that affects deer, elk, and moose. Human susceptibility to CWD remains unproven despite likely exposure to CWD-infected cervids. We used 2 nonhuman primate species, cynomolgus macaques and squirrel monkeys, as human models for CWD susceptibility. CWD was inoculated into these 2 species by intracerebral and oral routes. After intracerebral inoculation of squirrel monkeys, 7 of 8 CWD isolates induced a clinical wasting syndrome within 33–53 months. The monkeys’ brains showed spongiform encephalopathy and protease-resistant prion protein (PrPres) diagnostic of prion disease. After oral exposure, 2 squirrel monkeys had PrPres in brain, spleen, and lymph nodes at 69 months postinfection. In contrast, cynomolgus macaques have not shown evidence of clinical disease as of 70 months postinfection. Thus, these 2 species differed in susceptibility to CWD. Because humans are evolutionarily closer to macaques than to squirrel monkeys, they may also be resistant to CWD.
Transmissible spongiform encephalopathies (TSEs), or prion diseases, are neurodegenerative diseases that affect many mammalian species. Some examples include bovine spongiform encephalopathy (BSE) in cattle, scrapie in sheep and goats, Creutzfeldt-Jakob disease (CJD) in humans, and chronic wasting disease (CWD) in cervids. CWD was first found in captive deer in Colorado in 1967 (1) and was later identified in several US states and Canadian provinces (2). Epidemiologic evidence suggests that CWD continues to spread among cervid populations in North America (3), creating concern that CWD may cross species barriers to infect humans or domestic animals that may be eaten by humans. Thus, the host range of CWD and the level of protection provided by species barriers should be determined.
Substantial progress has been made in testing species barriers for CWD by using transgenic mice expressing species-specific prion protein (PrP), by direct infection into new species, or by in vitro conversion assays. The most sensitive method for testing susceptibility to TSE agents is intracerebral injection. Unfortunately, this route does not mimic most natural situations and only enables assessment of whether the possibility of transmission exists. Hamir et al. infected cattle and sheep with CWD by the intracerebral route and found protease-resistant PrP (PrPres) in 5 of 13 cattle and 2 of 8 sheep, which indicated that these ruminant species can propagate CWD (4,5). However, oral exposure in these hosts apparently does not cause disease (2).
CWD cross-species transmission to nonagricultural and laboratory animals has shown variable levels of susceptibility depending on the route of transmission. For example, ferrets were 100% susceptible to CWD by intracerebral infection but were not susceptible to oral infection (6,7). Mink were only 25% susceptible to CWD by intracerebral infection and were not susceptible to oral infection (8). CWD has been successfully transmitted and adapted to laboratory rodents, including hamsters, transgenic mice expressing hamster PrP, and transgenic mice overexpressing mouse PrP (9,10). In contrast, transgenic mice expressing human PrP were not susceptible to CWD by intracerebral infection (11,12), a finding that provided evidence for a human species barrier against CWD infection. However, work started in 1980 and published in 2005 by Marsh et al. showed that 2 squirrel monkeys (Saimiri sciureus) infected by the intracerebral route with brain homogenate from a single CWD-affected mule deer became clinically sick at 31 and 34 months postinfection, and both were positive for PrPres (13). This evidence that at least 1 species of nonhuman primate was susceptible to CWD weakened the conclusion that humans may be protected from CWD by a species barrier.
We addressed 4 questions raised by the original observation that squirrel monkeys are susceptible to CWD (13). First, we compared intracerebral and oral routes of infection. This comparison was of interest because the oral route is likely to be an important natural route of disease transmission, and susceptibility is known to be lower by this route in most models. Second, we compared 2 species of nonhuman primates, cynomolgus macaques (Macaca fascicularis) and squirrel monkeys, each of which has previously shown susceptibility to various human prion diseases (14–16). However, humans are believed to be evolutionarily closer to cynomolgus macaques than to squirrel monkeys (17), and cynomolgus macaques may be a more accurate model for a human species barrier. Third, because only 1 CWD source was tested by Marsh et al. (13), we studied 8 different pools of CWD representing wild and captive cervids, including mule deer, white-tailed deer, and elk, from separate regions in the United States. Fourth, we tested the species tropism of CWD agent passaged in squirrel monkeys.
As new CWD foci continue to emerge among cervid populations, the risk for CWD transmission to humans needs to be assessed. We used 2 monkey species and 2 routes of inoculation to test the susceptibility of primates to 8 different pools of CWD. To date, we have verified CWD in 11 of 13 intracerebrally inoculated squirrel monkeys; average incubation period was 41 months (range 33–53 months). Using a single CWD pool, Marsh et al. noted infection in 2 of 2 squirrel monkeys 31–34 months after intracerebral inoculation (13). Intracerebral inoculation of squirrel monkeys with other TSE agents, including agents of kuru, variant CJD, sporadic CJD, and sheep scrapie, had incubation periods of ≈24 months and attack rates of ≈100% (14,15,32). The extended incubation periods and lower attack rates for our squirrel monkeys may result from a partial species barrier to CWD.
The signs of wasting syndrome in CWD-infected monkeys were similar to those of CWD infection in cervids, in which loss of body condition is nearly always a major component of infection and neurologic deficits vary (2). The correlation of clinical signs between CWD in cervids and squirrel monkeys suggests that CWD might affect a common brain region in each species. We observed PrPres deposition in squirrel monkeys primarily in the frontal lobe of the cerebral cortex, claustrum, putamen, and thalamus. Cervids typically have the most abundant and predictable PrPres in the dorsal motor vagus nucleus (obex), olfactory cortex, and diencephalon (including thalamus, hypothalamus, metathalamus, and epithalamus) (2,33). A plausible hypothesis could be that disruption of regions within the hypothalamus and thalamus leads to a metabolic imbalance, resulting in a severe wasting syndrome.
We did not observe a strong correlation between infectivity titer inoculated and attack incidence or incubation period (Table 1). One potential explanation is that the variation in speed of disease progression might not be relevant given the low number of animals in each group. A second possibility is that our squirrel monkeys varied at PrP alleles that may affect CWD susceptibility. However, analysis of 23 squirrel monkeys showed no PrP sequence differences correlating with susceptibility to CWD (Tables 1, 2, 4). A third possibility is that genes other than the gene for PrP might influence CWD susceptibility.
For humans, eating infected or contaminated tissue is a likely route of CWD exposure. In other animal models, oral transmission of TSE is generally 1,000-fold less effective than direct intracerebral challenge and results in longer incubation periods and lower efficiency of disease transmission. In our oral transmission experiments, we found evidence of CWD infection in 3 monkeys; 2 at 69 mpi had abundant PrPres in brain and lower levels in spleen and lymph nodes, and 1 euthanized at 39 mpi had PrPres in lymphatic tissues only. Thus, transmission seems to be slower by the oral route than by the intracerebral route, and other orally infected monkeys may be affected in the future.
Cynomolgus macaques are evolutionarily closer to humans than are squirrel monkeys (17). At nearly 6 years postinoculation, no macaques have shown clinical signs of CWD. Intracerebral inoculation of cynomolgus macaques with BSE causes disease in 3 years; human variant CJD requires 2–3 years, and human sporadic CJD requires 5 years (16,34). However, oral inoculation of cynomolgus macaques with BSE agent required a minimum of 5 years before clinical disease was observed (35). Therefore, we cannot rule out CWD transmission to cynomolgus macaques.
The PrP gene sequence can influence cross-species transmission of prion disease. Therefore, we compared squirrel monkey and cynomolgus macaque PrP gene sequences to look for differences that might account for different susceptibilities of these monkeys to CWD. In the PrP gene excluding the signal peptide, deer differed from squirrel monkeys at 17 residues and from cynomolgus macaques at 16 residues, but 14 of these differing residues were identical in squirrel monkeys and macaques (Figure 4). Therefore, there are only 2 residues in cynomolgus macaques (100 and 108) and 3 residues in squirrel monkeys (56, 159 and 182) at which these monkeys differ from deer and also from each other. These residues might play a role in susceptibility differences seen in our study.
Human exposure to CWD-infected cervids in past decades is likely. The highest levels of prion infectivity are present in the central nervous system and lymphatic tissues of CWD-infected cervids; contamination of knives, saws, and muscles with these tissues can easy occur when processing game. Despite the likelihood of exposures, epidemiologic studies of humans living in CWD-endemic areas of Colorado and Wyoming during 1979–2001 have not shown any increases in human TSE cases (36,37). Ongoing studies by the Colorado Department of Public Health and Environmental Human Prion Disease Surveillance Program, in conjunction with the University of Colorado School of Medicine, have also concluded that no convincing cases of CWD transmission to humans have been detected in Colorado (38). However, if CWD in humans appears like a wasting syndrome similar to that observed in the squirrel monkeys in our study, affected persons might receive a diagnosis of a metabolic disorder and never be tested for TSE. Fortunately, additional laboratory data are consistent with the epidemiologic data, and these results support the conclusion that a species barrier protects humans from CWD infection (11–13,20,36,37).
> Because humans are evolutionarily closer to macaques than to squirrel monkeys, they may also be resistant to CWD.
> This evidence that at least 1 species of nonhuman primate was susceptible to CWD weakened the conclusion that humans may be protected from CWD by a species barrier.
> Therefore, we cannot rule out CWD transmission to cynomolgus macaques.
> However, if CWD in humans appears like a wasting syndrome similar to that observed in the squirrel monkeys in our study, affected persons might receive a diagnosis of a metabolic disorder and never be tested for TSE.
> Fortunately, additional laboratory data are consistent with the epidemiologic data, and these results support the conclusion that a species barrier protects humans from CWD infection
I can only quote what an old TSE prion scientist stated about this study last night ;
this is a gross misrepresentation of the species barrier. evolutionary distance is a very dangerous, unreliable proxy for transmission, as seen by the situation in rodents.
i really oppose this stance of encouraging people to eat cwd deer and elk and scrapie sheep. exact opposite of precautionary principle. very dangerous experiment.
I could not agree more. ...TSS
UPDATED CORRESPONDENCE FROM AUTHORS OF THIS STUDY I.E. COLBY, PRUSINER ET AL, ABOUT MY CONCERNS OF THE DISCREPANCY BETWEEN THEIR FIGURES AND MY FIGURES OF THE STUDIES ON CWD TRANSMISSION TO CATTLE ;
CWD to cattle figures CORRECTION
I believe the statement and quote below is incorrect ;
"CWD has been transmitted to cattle after intracerebral inoculation, although the infection rate was low (4 of 13 animals [Hamir et al. 2001]). This finding raised concerns that CWD prions might be transmitted to cattle grazing in contaminated pastures."
Please see ;
Within 26 months post inoculation, 12 inoculated animals had lost weight, revealed abnormal clinical signs, and were euthanatized. Laboratory tests revealed the presence of a unique pattern of the disease agent in tissues of these animals. These findings demonstrate that when CWD is directly inoculated into the brain of cattle, 86% of inoculated cattle develop clinical signs of the disease.
" although the infection rate was low (4 of 13 animals [Hamir et al. 2001]). "
shouldn't this be corrected, 86% is NOT a low rate. ...
Terry S. Singeltary Sr. P.O. Box 42 Bacliff, Texas USA 77518
Thanks so much for your updates/comments. We intend to publish as rapidly as possible all updates/comments that contribute substantially to the topic under discussion.
re-Prions David W. Colby1,* and Stanley B. Prusiner1,2 + Author Affiliations
1Institute for Neurodegenerative Diseases, University of California, San Francisco, San Francisco, California 94143 2Department of Neurology, University of California, San Francisco, San Francisco, California 94143 Correspondence: firstname.lastname@example.org
Mule deer, white-tailed deer, and elk have been reported to develop CWD. As the only prion disease identified in free-ranging animals, CWD appears to be far more communicable than other forms of prion disease. CWD was first described in 1967 and was reported to be a spongiform encephalopathy in 1978 on the basis of histopathology of the brain. Originally detected in the American West, CWD has spread across much of North America and has been reported also in South Korea. In captive populations, up to 90% of mule deer have been reported to be positive for prions (Williams and Young 1980). The incidence of CWD in cervids living in the wild has been estimated to be as high as 15% (Miller et al. 2000). The development of transgenic (Tg) mice expressing cervid PrP, and thus susceptible to CWD, has enhanced detection of CWD and the estimation of prion titers (Browning et al. 2004; Tamgüney et al. 2006). Shedding of prions in the feces, even in presymptomatic deer, has been identified as a likely source of infection for these grazing animals (Williams and Miller 2002; Tamgüney et al. 2009b). CWD has been transmitted to cattle after intracerebral inoculation, although the infection rate was low (4 of 13 animals [Hamir et al. 2001]). This finding raised concerns that CWD prions might be transmitted to cattle grazing in contaminated pastures.
----- Original Message -----
From: David Colby To: email@example.com
Sent: Tuesday, March 01, 2011 8:25 AM
Subject: Re: FW: re-Prions David W. Colby1,* and Stanley B. Prusiner1,2 + Author Affiliations
Dear Terry Singeltary,
Thank you for your correspondence regarding the review article Stanley Prusiner and I recently wrote for Cold Spring Harbor Perspectives. Dr. Prusiner asked that I reply to your message due to his busy schedule. We agree that the transmission of CWD prions to beef livestock would be a troubling development and assessing that risk is important. In our article, we cite a peer-reviewed publication reporting confirmed cases of laboratory transmission based on stringent criteria. The less stringent criteria for transmission described in the abstract you refer to lead to the discrepancy between your numbers and ours and thus the interpretation of the transmission rate. We stand by our assessment of the literature--namely that the transmission rate of CWD to bovines appears relatively low, but we recognize that even a low transmission rate could have important implications for public health and we thank you for bringing attention to this matter.
Warm Regards, David Colby -- David Colby, PhD
Assistant Professor Department of Chemical Engineering University of Delaware
SNIP...SEE FULL TEXT ;
Sunday, August 19, 2012
Susceptibility of cattle to the agent of chronic wasting disease from elk after intracranial inoculation 2012
Research Project: TRANSMISSION, DIFFERENTIATION, AND PATHOBIOLOGY OF TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHIES Location: Virus and Prion Research Unit
PO-081: Chronic wasting disease in the cat— Similarities to feline spongiform encephalopathy (FSE)
PO-081: Chronic wasting disease in the cat— Similarities to feline spongiform encephalopathy (FSE)
TSE & HOUNDS
GAH WELLS (very important statement here...TSS)
AS implied in the Inset 25 we must not _ASSUME_ that transmission of BSE to other species will invariably present pathology typical of a scrapie-like disease.
OR-09: Canine spongiform encephalopathy—A new form of animal prion disease
Monique David, Mourad Tayebi UT Health; Houston, TX USA
It was also hypothesized that BSE might have originated from an unrecognized sporadic or genetic case of bovine prion disease incorporated into cattle feed or even cattle feed contaminated with prion-infected human remains.1 However, strong support for a genetic origin of BSE has recently been demonstrated in an H-type BSE case exhibiting the novel mutation E211K.2 Furthermore, a specific prion protein strain causing BSE in cattle is believed to be the etiological agent responsible for the novel human prion disease, variant Creutzfeldt-Jakob disease (vCJD).3 Cases of vCJD have been identified in a number countries, including France, Italy, Ireland, the Netherlands, Canada, Japan, US and the UK with the largest number of cases. Naturally occurring feline spongiform encephalopathy of domestic cats4 and spongiform encephalopathies of a number of zoo animals so-called exotic ungulate encephalopathies5,6 are also recognized as animal prion diseases, and are thought to have resulted from the same BSE-contaminated food given to cattle and humans, although and at least in some of these cases, a sporadic and/or genetic etiology cannot be ruled out. The canine species seems to display resistance to prion disease and no single case has so far been reported.7,8
Here, we describe a case of a 9 week old male Rottweiler puppy presenting neurological deficits; and histological examination revealed spongiform vacuolation characteristic of those associated with prion diseases.9 Initial biochemical studies using anti-PrP antibodies revealed the presence of partially proteinase K-resistant fragment by western blotting. Furthermore, immunohistochemistry revealed spongiform degeneration consistent with those found in prion disease and displayed staining for PrPSc in the cortex.
Of major importance, PrPSc isolated from the Rottweiler was able to cross the species barrier transmitted to hamster in vitro with PMCA and in vivo (one hamster out of 5). Futhermore, second in vivo passage to hamsters, led to 100% attack rate (n = 4) and animals displayed untypical lesional profile and shorter incubation period.
In this study, we show that the canine species might be sensitive to prion disease and that PrPSc isolated from a dog can be transmitted to dogs and hamsters in vitro using PMCA and in vivo to hamsters.
If our preliminary results are confirmed, the proposal will have a major impact on animal and public health and would certainly lead to implementing new control measures for ‘canine spongiform encephalopathy’ (CSE).
1. Colchester AC, Colchester NT. The origin of bovine spongiform encephalopathy: the human prion disease hypothesis. Lancet 2005; 366:856-61; PMID:16139661; http:// dx.doi.org/10.1016/S0140-6736(05)67218-2.
2. Richt JA, Hall SM. BSE case associated with prion protein gene mutation. PLoS Pathog 2008; 4:e1000156; PMID:18787697; http://dx.doi.org/10.1371/journal. ppat.1000156.
3. Collinge J. Human prion diseases and bovine spongiform encephalopathy (BSE). Hum Mol Genet 1997; 6:1699-705; PMID:9300662; http://dx.doi.org/10.1093/ hmg/6.10.1699.
4. Wyatt JM, Pearson GR, Smerdon TN, Gruffydd-Jones TJ, Wells GA, Wilesmith JW. Naturally occurring scrapie-like spongiform encephalopathy in five domestic cats. Vet Rec 1991; 129:233-6; PMID:1957458; http://dx.doi.org/10.1136/vr.129.11.233.
5. Jeffrey M, Wells GA. Spongiform encephalopathy in a nyala (Tragelaphus angasi). Vet Pathol 1988; 25:398-9; PMID:3232315; http://dx.doi.org/10.1177/030098588802500514.
6. Kirkwood JK, Wells GA, Wilesmith JW, Cunningham AA, Jackson SI. Spongiform encephalopathy in an arabian oryx (Oryx leucoryx) and a greater kudu (Tragelaphus strepsiceros). Vet Rec 1990; 127:418-20; PMID:2264242.
7. Bartz JC, McKenzie DI, Bessen RA, Marsh RF, Aiken JM. Transmissible mink encephalopathy species barrier effect between ferret and mink: PrP gene and protein analysis. J Gen Virol 1994; 75:2947-53; PMID:7964604; http://dx.doi.org/10.1099/0022-1317- 75-11-2947.
8. Lysek DA, Schorn C, Nivon LG, Esteve-Moya V, Christen B, Calzolai L, et al. Prion protein NMR structures of cats, dogs, pigs, and sheep. Proc Natl Acad Sci U S A 2005; 102:640-5; PMID:15647367; http://dx.doi.org/10.1073/pnas.0408937102.
9. Budka H. Neuropathology of prion diseases. Br Med Bull 2003; 66:121-30; PMID:14522854; http://dx.doi.org/10.1093/bmb/66.1.121.
Monday, March 8, 2010
Canine Spongiform Encephalopathy aka MAD DOG DISEASE
Thursday, May 31, 2012
CHRONIC WASTING DISEASE CWD PRION2012 Aerosol, Inhalation transmission, Scrapie, cats, species barrier, burial, and more
CHRONIC WASTING DISEASE, CWD, AND THE DEER PENS AT THE FOOT HILLS CAMPUS
*** Spraker suggested an interesting explanation for the occurrence of CWD. The deer pens at the Foot Hills Campus were built some 30-40 years ago by a Dr. Bob Davis. At or about that time, allegedly, some scrapie work was conducted at this site. When deer were introduced to the pens they occupied ground that had previously been occupied by sheep.
(PLEASE NOTE SOME OF THESE OLD UK GOVERNMENT FILE URLS ARE SLOW TO OPEN, AND SOMETIMES YOU MAY HAVE TO CLICK ON MULTIPLE TIMES, PLEASE BE PATIENT, ANY PROBLEMS PLEASE WRITE ME PRIVATELY, AND I WILL TRY AND FIX OR SEND YOU OLD PDF FILE...TSS)
PERCEPTIONS OF UNCONVENTIONAL SLOW VIRUS DISEASES OF ANIMALS IN USA
REPORT OF A VISIT TO THE USA APRIL-MAY 1989
Mule deer transmissions of CWD were by intracerebral inoculation and compared with natural cases 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 inoculam (?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.
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.
2011 Annual Report
Research Project: TRANSMISSION, DIFFERENTIATION, AND PATHOBIOLOGY OF TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHIES Location: Virus and Prion Research Unit
2011 Annual Report
In Objective 1, Assess cross-species transmissibility of transmissible spongiform encephalopathies (TSEs) in livestock and wildlife, numerous experiments assessing the susceptibility of various TSEs in different host species were conducted. Most notable is deer inoculated with scrapie, which exhibits similarities to chronic wasting disease (CWD) in deer suggestive of sheep scrapie as an origin of CWD.
4.Accomplishments 1. Deer inoculated with domestic isolates of sheep scrapie. Scrapie-affected deer exhibit 2 different patterns of disease associated prion protein. In some regions of the brain the pattern is much like that observed for scrapie, while in others it is more like chronic wasting disease (CWD), the transmissible spongiform encephalopathy typically associated with deer. This work conducted by ARS scientists at the National Animal Disease Center, Ames, IA suggests that an interspecies transmission of sheep scrapie to deer may have been the origin of CWD. This is important for husbandry practices with both captive deer, elk and sheep for farmers and ranchers attempting to keep their herds and flocks free of CWD and scrapie.
now, years later, see the latest studies here on scrapie and cwd ;
PO-039: A comparison of scrapie and chronic wasting disease in white-tailed deer
Justin Greenlee, Jodi Smith, Eric Nicholson US Dept. Agriculture; Agricultural Research Service, National Animal Disease Center; Ames, IA USA
Interspecies transmission studies afford the opportunity to better understand the potential host range and origins of prion diseases. The purpose of these experiments was to determine susceptibility of white-tailed deer (WTD) to scrapie and to compare the resultant clinical signs, lesions, and molecular profiles of PrPSc to those of chronic wasting disease (CWD). We inoculated WTD intracranially (IC; n = 5) and by a natural route of exposure (concurrent oral and intranasal (IN); n = 5) with a US scrapie isolate. All deer were inoculated with a 10% (wt/vol) brain homogenate from sheep with scrapie (1ml IC, 1 ml IN, 30 ml oral). All deer inoculated by the intracranial route had evidence of PrPSc accumulation. PrPSc was detected in lymphoid tissues as early as 7 months-post-inoculation (PI) and a single deer that was necropsied at 15.6 months had widespread distribution of PrPSc highlighting that PrPSc is widely distributed in the CNS and lymphoid tissues prior to the onset of clinical signs. IC inoculated deer necropsied after 20 months PI (3/5) had clinical signs, spongiform encephalopathy, and widespread distribution of PrPSc in neural and lymphoid tissues. The results of this study suggest that there are many similarities in the manifestation of CWD and scrapie in WTD after IC inoculation including early and widespread presence of PrPSc in lymphoid tissues, clinical signs of depression and weight loss progressing to wasting, and an incubation time of 21-23 months. Moreover, western blots (WB) done on brain material from the obex region have a molecular profile similar to CWD and distinct from tissues of the cerebrum or the scrapie inoculum. However, results of microscopic and IHC examination indicate that there are differences between the lesions expected in CWD and those that occur in deer with scrapie: amyloid plaques were not noted in any sections of brain examined from these deer and the pattern of immunoreactivity by IHC was diffuse rather than plaque-like. After a natural route of exposure, 100% of WTD were susceptible to scrapie. Deer developed clinical signs of wasting and mental depression and were necropsied from 28 to 33 months PI. Tissues from these deer were positive for PrPSc by IHC and WB. Similar to IC inoculated deer, samples from these deer exhibited two different molecular profiles: samples from obex resembled CWD whereas those from cerebrum were similar to the original scrapie inoculum. On further examination by WB using a panel of antibodies, the tissues from deer with scrapie exhibit properties differing from tissues either from sheep with scrapie or WTD with CWD. Samples from WTD with CWD or sheep with scrapie are strongly immunoreactive when probed with mAb P4, however, samples from WTD with scrapie are only weakly immunoreactive. In contrast, when probed with mAb’s 6H4 or SAF 84, samples from sheep with scrapie and WTD with CWD are weakly immunoreactive and samples from WTD with scrapie are strongly positive. This work demonstrates that WTD are highly susceptible to sheep scrapie, but on first passage, scrapie in WTD is differentiable from CWD.
White-tailed Deer are Susceptible to Scrapie by Natural Route of Infection
Jodi D. Smith, Justin J. Greenlee, and Robert A. Kunkle; Virus and Prion Research Unit, National Animal Disease Center, USDA-ARS
Interspecies transmission studies afford the opportunity to better understand the potential host range and origins of prion diseases. Previous experiments demonstrated that white-tailed deer are susceptible to sheep-derived scrapie by intracranial inoculation. The purpose of this study was to determine susceptibility of white-tailed deer to scrapie after a natural route of exposure. Deer (n=5) were inoculated by concurrent oral (30 ml) and intranasal (1 ml) instillation of a 10% (wt/vol) brain homogenate derived from a sheep clinically affected with scrapie. Non-inoculated deer were maintained as negative controls. All deer were observed daily for clinical signs. Deer were euthanized and necropsied when neurologic disease was evident, and tissues were examined for abnormal prion protein (PrPSc) by immunohistochemistry (IHC) and western blot (WB). One animal was euthanized 15 months post-inoculation (MPI) due to an injury. At that time, examination of obex and lymphoid tissues by IHC was positive, but WB of obex and colliculus were negative. Remaining deer developed clinical signs of wasting and mental depression and were necropsied from 28 to 33 MPI. Tissues from these deer were positive for scrapie by IHC and WB. Tissues with PrPSc immunoreactivity included brain, tonsil, retropharyngeal and mesenteric lymph nodes, hemal node, Peyer’s patches, and spleen. This work demonstrates for the first time that white-tailed deer are susceptible to sheep scrapie by potential natural routes of inoculation. In-depth analysis of tissues will be done to determine similarities between scrapie in deer after intracranial and oral/intranasal inoculation and chronic wasting disease resulting from similar routes of inoculation.
see full text ;
Envt.11: Swine Are Susceptible to Chronic Wasting Disease by Intracerebral Inoculation
Justin Greenlee,† Robert Kunkle and Jodi Smith National Animal Disease Center, ARS, USDA; Ames, IA USA †Presenting author; Email: firstname.lastname@example.org
Transmissible spongiform encephalopathies (TSEs, prion diseases) are chronic neurodegenerative diseases that occur in humans, cattle, sheep, goats, cervids and a number of laboratory animal models. There is no evidence of the natural occurrence of any form of TSE in the pig, but pigs have been shown to be susceptible to Bovine Spongiform Encephalopathy (BSE) infection by multiple-route parenteral challenge. However, pigs orally exposed at eight weeks of age to large amounts of brain from cattle clinically affected with BSE did not support infection after seven years of observation. In the US, feeding of ruminant by-products to ruminants is prohibited, but feeding of ruminant materials to swine, mink and poultry still occurs. Although unlikely, the potential for swine to have access to TSE-contaminated feedstuffs exists. The potential for swine to serve as a host for the agent of chronic wasting disease (CWD) is unknown. The purpose of this study was to perform intracerebral inoculation of the CWD agent to determine the potential of swine as a host for the CWD agent and their clinical susceptibility. This study utilized 26 swine randomly divided into controls (n = 6) and intracranial inoculates (n = 20). CWD inoculum was a pooled 10% (w/v) homogenate derived from three white-tailed deer clinically ill with CWD from three different sources (elk, white-tailed deer, mule deer) and was given by a single intracranial injection of 0.75 ml. Necropsies were done on ten animals at six months post inoculation (PI), at approximately the time the pigs were expected to reach market weight. Additional pigs have been necropsied due to intercurrent disease (primarily lameness) over the course of the study (29–64 months). Samples collected at necropsy were examined for spongiform change after routine staining (hematoxylin and eosin) and for immunoreactivity to prion protein (PrPSc) by immunohistochemistry. Further, brain samples from at least two regions were tested by western blot. No results suggestive of spongiform encephalopathy were obtained from animals necropsied at six months PI, but positive results after an incubation period of only six months would be uncharacteristic. A single animal was positive for CWD by IHC and WB at 64 months PI. Two inoculated pigs and one control pig remain alive, so it is not possible to determine the attack rate of CWD in swine at this time. However, lack of positive results in pigs necropsied at 29–56 months PI and the long incubation of the single positive case suggest that swine are unlikely to be affected by CWD if inoculated by a natural route.
Chronic Wasting Disease Susceptibility of Four North American Rodents
Chad J. Johnson1*, Jay R. Schneider2, Christopher J. Johnson2, Natalie A. Mickelsen2, Julia A. Langenberg3, Philip N. Bochsler4, Delwyn P. Keane4, Daniel J. Barr4, and Dennis M. Heisey2 1University of Wisconsin School of Veterinary Medicine, Department of Comparative Biosciences, 1656 Linden Drive, Madison WI 53706, USA 2US Geological Survey, National Wildlife Health Center, 6006 Schroeder Road, Madison WI 53711, USA 3Wisconsin Department of Natural Resources, 101 South Webster Street, Madison WI 53703, USA 4Wisconsin Veterinary Diagnostic Lab, 445 Easterday Lane, Madison WI 53706, USA *Corresponding author email: email@example.com
We intracerebrally challenged four species of native North American rodents that inhabit locations undergoing cervid chronic wasting disease (CWD) epidemics. The species were: deer mice (Peromyscus maniculatus), white-footed mice (P. leucopus), meadow voles (Microtus pennsylvanicus), and red-backed voles (Myodes gapperi). The inocula were prepared from the brains of hunter-harvested white-tailed deer from Wisconsin that tested positive for CWD. Meadow voles proved to be most susceptible, with a median incubation period of 272 days. Immunoblotting and immunohistochemistry confirmed the presence of PrPd in the brains of all challenged meadow voles. Subsequent passages in meadow voles lead to a significant reduction in incubation period. The disease progression in red-backed voles, which are very closely related to the European bank vole (M. glareolus) which have been demonstrated to be sensitive to a number of TSEs, was slower than in meadow voles with a median incubation period of 351 days. We sequenced the meadow vole and red-backed vole Prnp genes and found three amino acid (AA) differences outside of the signal and GPI anchor sequences. Of these differences (T56-, G90S, S170N; read-backed vole:meadow vole), S170N is particularly intriguing due its postulated involvement in "rigid loop" structure and CWD susceptibility. Deer mice did not exhibit disease signs until nearly 1.5 years post-inoculation, but appear to be exhibiting a high degree of disease penetrance. White-footed mice have an even longer incubation period but are also showing high penetrance. Second passage experiments show significant shortening of incubation periods. Meadow voles in particular appear to be interesting lab models for CWD. These rodents scavenge carrion, and are an important food source for many predator species. Furthermore, these rodents enter human and domestic livestock food chains by accidental inclusion in grain and forage. Further investigation of these species as potential hosts, bridge species, and reservoirs of CWD is required.
please see ;
Title: Transmission of chronic wasting disease of mule deer to Suffolk sheep following intracerebral inoculation
Hamir, Amirali Kunkle, Robert Cutlip, Randall - ARS RETIRED Miller, Janice - ARS RETIRED Williams, Elizabeth - UNIV OF WYOMING, LARAMIE Richt, Juergen
Submitted to: Journal of Veterinary Diagnostic Investigation Publication Type: Peer Reviewed Journal Publication Acceptance Date: June 20, 2006 Publication Date: November 1, 2006 Citation: Hamir, A.N., Kunkle, R.A., Cutlip, R.C., Miller, J.M., Williams, E.S., Richt, J.A. 2006. Transmission of chronic wasting disease of mule deer to Suffolk sheep following intracerebral inoculation. Journal of Veterinary Diagnostic Investigation. 18(6):558-565.
Interpretive Summary: Chronic wasting disease (CWD) has been identified in captive and free ranging deer and elk since 1967. To determine the transmissibility of CWD to sheep and to provide information about the disease and tests for detection of CWD in sheep, 8 lambs were inoculated with brain suspension from mule deer naturally affected with CWD. Two other lambs were kept as controls. Only 1 sheep developed clinical disease at 35 months after inoculation. The study was terminated at 72 months after the inoculation. At that time one other sheep was found to be positive for the disease. It is proposed that the host's genetic makeup may play a role in transmission of the disease to domestic sheep. Impact. This is the first study which shows that it is possible to transmit CWD to a small number of sheep. Technical Abstract: Chronic wasting disease (CWD) has been identified in captive and free-ranging cervids since 1967. To determine the transmissibility of CWD to sheep and to provide information about clinical course, lesions, and suitability of currently used diagnostic procedures for detection of CWD in sheep, 8 Suffolk lambs (4 QQ and 4 QR at codon 171 of prion protein (PRNP) gene) were inoculated intracerebrally with brain suspension from mule deer naturally affected with CWD (CWD**md). Two other lambs (1 QQ and 1 QR at codon 171 of PRNP gene) were kept as non-inoculated controls. Within 36 months post inoculation (MPI), 2 animals became recumbent and were euthanized. However, only 1 sheep (euthanized at 35 MPI) had shown clinical signs that were consistent with those of scrapie. Microscopic lesions of spongiform encephalopathy (SE) were seen in this sheep and its tissues were positive for the abnormal prion protein (PrPres) by immunohistochemistry and Western blot. Retrospective examination of the PRNP genotype of this animal revealed that it was heterozygous (AV) at codon 136. In the next 24 months, 3 other sheep were euthanized because of conditions unrelated to TSE. The remaining 3 sheep remained non-clinical at the termination of the study (72 MPI) and were euthanized at that time. One of these 3 revealed SE and its tissues were positive for PrPres. These findings demonstrate that it is possible to transmit CWD**md agent to sheep via the intracerebral route. However, the host genotype may play a significant part in successful transmission and incubation period of this agent.
Chronic wasting disease: Fingerprinting the culprit in risk assessments
Volume 6, Issue 1 January/February/March 2012 Pages 17 - 22 http://dx.doi.org/10.4161/pri.6.1.17776
Keywords: Fourier transform-infrared (FT-IR) spectroscopy, chronic wasting disease (CWD), prion, prion protein (PrP), prion typing, protein misfolding cyclic amplification (PMCA), risk assessment, seeding activity, strains, transmissible spongiform encephalopathies (TSE)
Authors: Martin L. Daus and Michael Beekes View affiliations Hide affiliations Martin L. Daus
P24 -Transmissible Spongiform Encephalopathies; Robert Koch-Institut; Berlin, Germany Michael Beekes Corresponding author: BeekesM@rki.de P24 -Transmissible Spongiform Encephalopathies; Robert Koch-Institut; Berlin, Germany
Abstract: Transmissible spongiform encephalopathies (prion diseases) in animals may be associated with a zoonotic risk potential for humans as shown by the occurrence of variant Creutzfeldt-Jakob disease in the wake of the bovine spongiform encephalopathy epidemic. Thus, the increasing exposure of humans in North America to cervid prions of chronic wasting disease (CWD) in elk and deer has prompted comprehensive risk assessments. The susceptibility of humans to CWD infections is currently under investigation in different studies using macaques as primate models. The necessity for such studies was recently reinforced when disease-associated prion protein and its seeding activity were detected in muscles of clinically inconspicuous CWD-infected white-tailed deer (WTD). Increasing evidence points to the existence of different CWD strains, and CWD prions may also change or newly emerge over time. Therefore, CWD isolates examined in macaques should be characterized as precisely as possible for their molecular identity. On this basis other CWD field samples collected in the past, present or future could be systematically compared with macaque-tested inocula in order to assess whether they are covered by the ongoing risk assessments in primates. CWD typing by Fourier transform-infrared spectroscopy of pathological prion protein may provide a method of choice for this purpose.
Exposure of humans to CWD prions
Chronic wasting disease is a TSE in white-tailed deer, mule deer, Rocky Mountain elk and moose. Over the past years this disease has shown a sustained spread in captive as well as free-ranging cervids in North America.6,7 The increasingly frequent and widespread 5 occurrence of affected animals is likely to augment the exposure of humans to the CWD agent. Prion infectivity or TSE-associated prion protein have been detected in the central and peripheral nervous system, in a variety of lymphoid tissues as well as in heart muscle, blood, saliva, feces and urine of CWD-infected cervids7. Also, infectious CWD agent was found in antler velvet of elk and in skeletal muscles of mule deer with chronic wasting disease.8,9 Thus, particularly persons processing cervid carcasses, users of medicinal products made from antler velvet and consumers of venison may be exposed to an elevated risk for contamination with CWD prions.
Recently, PrPTSE and its proteinaceous seeding activity could be directly demonstrated, for the first time, in skeletal muscles of CWD-infected cervids.10 The animals examined in this study were farmed and free-ranging WTD for which no clinical signs of CWD had been recognized. However, they had been officially confirmed positive for CWD based on the detection of PrPTSE in brain tissue or lymph nodes and were thus apparently in a state of pre or subclinical infection. Muscles from such clinically inconspicuous carrier animals appear more likely to enter the human food chain than meat from cervids that show symptoms of CWD. Whether this may provide a relevant mode for the inadvertent foodborne transmission of CWD prions is still unclear. Yet, the presence and seeding activity of PrPTSE in skeletal muscles of pre- or subclinically infected WTD reinforced the need to comprehensively assess whether humans are susceptible to zoonotic CWD infections.
Transmissibility to humans
The current state of epidemiological research suggests a rather robust barrier for the transmission of CWD to humans. Particularly, the surveillance of human prion diseases in areas with a long history of endemic CWD such as Colorado and Wyoming did not reveal evidence for zoonotic transmissions of the disease to cervid hunters or consumers of meat from elk and deer.6,11 However, as discussed by Belay et al.,6 the intensity of human exposure to CWD prions may increase due to a further spread and rising prevalence of the disease in cervids. Therefore, and with the generally long latency periods of human prion diseases in mind, previous epidemiological findings cannot be readily extrapolated. Until recently, experimental studies that pursued biochemical approaches or used transgenic mice to ascertain the susceptibility of humans to CWD infections consistently seemed to corroborate current epidemiological findings: CWD-infected cervid brain tissue did not seed the conversion of PrPC 133 into PrPres in PMCA assays using brain homogenate from macaques or transgenic mice expressing human PrPC as test substrate12 , and transgenic mice overexpressing human PrPC were resistant to infection after intracerebral challenge with CWD prions from mule deer.13 However, a study published by Barria et al.14 in March 2011 found that cervid PrPTSE can seed the conversion of human PrPC into PrPres by PMCA when the CWD agent has been previously passaged in vitro or in vivo. Specifically, this was demonstrated for CWD prions from naturally affected mule deer either passaged by serial PMCA using deer PrPC as conversion substrate or in transgenic mice expressing cervid PrPC. The authors of this study pointed out that CWD prions may undergo a gradual process of change and adaptation via successive passages in the cervid population. They concluded that the reported findings, if corroborated by infectivity assays, may imply “that CWD prions have the potential to infect humans and that this ability progressively increases with CWD spreading”.
Volume 18, Number 3—March 2012
Samuel E. Saunders1, Shannon L. Bartelt-Hunt, and Jason C. Bartz
Author affiliations: University of Nebraska-Lincoln, Omaha, Nebraska, USA (S.E. Saunders, S.L. Bartelt-Hunt); Creighton University, Omaha (J.C. Bartz)
Occurrence, Transmission, and Zoonotic Potential of Chronic Wasting Disease
Most epidemiologic studies and experimental work have suggested that the potential for CWD transmission to humans is low, and such transmission has not been documented through ongoing surveillance (2,3). In vitro prion replication assays report a relatively low efficiency of CWD PrPSc-directed conversion of human PrPc to PrPSc (30), and transgenic mice overexpressing human PrPc are resistant to CWD infection (31); these findings indicate low zoonotic potential. However, squirrel monkeys are susceptible to CWD by intracerebral and oral inoculation (32). Cynomolgus macaques, which are evolutionarily closer to humans than squirrel monkeys, are resistant to CWD infection (32). Regardless, the finding that a primate is orally susceptible to CWD is of concern.
Intraspecies and interspecies passage of the CWD agent may also increase the risk for zoonotic CWD transmission. The CWD prion agent is undergoing serial passage naturally as the disease continues to emerge. In vitro and in vivo intraspecies transmission of the CWD agent yields PrPSc with an increased capacity to convert human PrPc to PrPSc (30). Interspecies prion transmission can alter CWD host range (38) and yield multiple novel prion strains (3,28). The potential for interspecies CWD transmission (by cohabitating mammals) will only increase as the disease spreads and CWD prions continue to be shed into the environment. This environmental passage itself may alter CWD prions or exert selective pressures on CWD strain mixtures by interactions with soil, which are known to vary with prion strain (25), or exposure to environmental or gut degradation.
Given that prion disease in humans can be difficult to diagnose and the asymptomatic incubation period can last decades, continued research, epidemiologic surveillance, and caution in handling risky material remain prudent as CWD continues to spread and the opportunity for interspecies transmission increases. Otherwise, similar to what occurred in the United Kingdom after detection of variant CJD and its subsequent link to BSE, years of prevention could be lost if zoonotic transmission of CWD is subsequently identified,...
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Zoonotic Potential of CWD: Experimental Transmissions to Non-Human Primates
Emmanuel Comoy,1,† Valérie Durand,1 Evelyne Correia,1 Aru Balachandran,2 Jürgen Richt,3 Vincent Beringue,4 Juan-Maria Torres,5 Paul Brown,1 Bob Hills6 and Jean-Philippe Deslys1
1Atomic Energy Commission; Fontenay-aux-Roses, France; 2Canadian Food Inspection Agency; Ottawa, ON Canada; 3Kansas State University; Manhattan, KS USA; 4INRA; Jouy-en-Josas, France; 5INIA; Madrid, Spain; 6Health Canada; Ottawa, ON Canada
†Presenting author; Email: firstname.lastname@example.org
The constant increase of chronic wasting disease (CWD) incidence in North America raises a question about their zoonotic potential. A recent publication showed their transmissibility to new-world monkeys, but no transmission to old-world monkeys, which are phylogenetically closer to humans, has so far been reported. Moreover, several studies have failed to transmit CWD to transgenic mice overexpressing human PrP. Bovine spongiform encephalopathy (BSE) is the only animal prion disease for which a zoonotic potential has been proven. We described the transmission of the atypical BSE-L strain of BSE to cynomolgus monkeys, suggesting a weak cattle-to-primate species barrier. We observed the same phenomenon with a cattleadapted strain of TME (Transmissible Mink Encephalopathy). Since cattle experimentally exposed to CWD strains have also developed spongiform encephalopathies, we inoculated brain tissue from CWD-infected cattle to three cynomolgus macaques as well as to transgenic mice overexpressing bovine or human PrP. Since CWD prion strains are highly lymphotropic, suggesting an adaptation of these agents after peripheral exposure, a parallel set of four monkeys was inoculated with CWD-infected cervid brains using the oral route. Nearly four years post-exposure, monkeys exposed to CWD-related prion strains remain asymptomatic. In contrast, bovinized and humanized transgenic mice showed signs of infection, suggesting that CWD-related prion strains may be capable of crossing the cattle-to-primate species barrier. Comparisons with transmission results and incubation periods obtained after exposure to other cattle prion strains (c-BSE, BSE-L, BSE-H and cattle-adapted TME) will also be presented, in order to evaluate the respective risks of each strain.
Pathological Prion Protein (PrPTSE) in Skeletal Muscles of Farmed and Free Ranging White-Tailed Deer Infected with Chronic Wasting Disease
Martin L. Daus,1,† Johanna Breyer,2 Katjs Wagenfuehr,1 Wiebke Wemheuer,2 Achim Thomzig,1 Walter Schulz-Schaeffer2 and Michael Beekes1 1Robert Koch Institut; P24 TSE; Berlin, Germany; 2Department of Neuropathology, Prion and Dementia Research Unit, University Medical Center Göttingen; Göttingen, Germany
†Presenting author; Email: email@example.com
Chronic wasting disease (CWD) is a contagious, rapidly spreading transmissible spongiform encephalopathy (TSE) occurring in cervids in North America. Despite efficient horizontal transmission of CWD among cervids natural transmission of the disease to other species has not yet been observed. Here, we report a direct biochemical demonstration of pathological prion protein PrPTSE and of PrPTSE-associated seeding activity in skeletal muscles of CWD-infected cervids. The presence of PrPTSE was detected by Western- and postfixed frozen tissue blotting, while the seeding activity of PrPTSE was revealed by protein misfolding cyclic amplification (PMCA). The concentration of PrPTSE in skeletal muscles of CWD-infected WTD was estimated to be approximately 2000- to 10000-fold lower than in brain tissue. Tissue-blot-analyses revealed that PrPTSE was located in muscle- associated nerve fascicles but not, in detectable amounts, in myocytes. The presence and seeding activity of PrPTSE in skeletal muscle from CWD-infected cervids suggests prevention of such tissue in the human diet as a precautionary measure for food safety, pending on further clarification of whether CWD may be transmissible to humans.
Sunday, January 22, 2012
Chronic Wasting Disease CWD cervids interspecies transmission
now, let’s see what the authors said about this casual link, personal communications years ago. see where it is stated NO STRONG evidence. so, does this mean there IS casual evidence ????
CONCLUSIONS: Although the occurrence of 3 unusually young patients with CJD who consumed venison suggested a possible relationship with CWD, our follow-up investigation found no strong evidence for a causal link. Ongoing CJD surveillance remains important for continuing to assess the risk, if any, of CWD transmission to humans.
“Our conclusion stating that we found no strong evidence of CWD transmission to humans”
From: TSS (216-119-163-189.ipset45.wt.net)
Subject: CWD aka MAD DEER/ELK TO HUMANS ???
Date: September 30, 2002 at 7:06 am PST
From: "Belay, Ermias"
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
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
Sent: Sunday, September 29, 2002 10:15 AM
To: firstname.lastname@example.org; email@example.com; 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
*** twenty-seven CJD patients who regularly consumed venison were reported to the Surveillance Center***,
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CWD ongoing experiment on humans, long term $$$
Monday, November 14, 2011
WYOMING Creutzfeldt Jakob Disease, CWD, TSE, PRION REPORTING 2011
Wednesday, November 16, 2011
Wisconsin Creutzfeldt Jakob Disease, CWD, TSE, PRION REPORTING 2011
Observation| March 2007
Colorado Surveillance Program for Chronic Wasting Disease Transmission to HumansLessons From 2 Highly Suspicious but Negative CasesFREE
C. Alan Anderson, MD; Patrick Bosque, MD; Christopher M. Filley, MD; David B. Arciniegas, MD; B. K. Kleinschmidt-DeMasters, MD; W. John Pape, BS; Kenneth L. Tyler, MD
[+] Author Affiliations
Arch Neurol. 2007;64(3):439-441. doi:10.1001/archneur.64.3.439.
Objective To describe 2 patients with rapidly progressive dementia and risk factors for exposure to chronic wasting disease (CWD) in whom extensive testing negated the possible transmission of CWD.
Design/Methods We describe the evaluation of 2 young adults with initial exposure histories and clinical presentations that suggested the possibility of CWD transmission to humans.
Patients A 52-year-old woman with possible laboratory exposure to CWD and a 25-year-old man who had consumed meat from a CWD endemic area.
Interventions Clinical evaluation, neuropathological examination, and genetic testing.
Results Neuropathological and genetic assessment in the 2 patients proved the diagnoses of early-onset Alzheimer disease and a rare genetic prion disease.
Conclusion No convincing cases of CWD transmission to humans have been detected in our surveillance program.
CASE 1 .
A 52-year-old right-handed woman presented with a 1-year history of progressive memory loss, language impairment, visuospatial disturbance, and myoclonus. She related that she had been a histology technician in a laboratory that processed tissue specimens from deer and elk with CWD and had handled specimens without wearing gloves. Both she and her family expressed significant concerns about the possibility of transdermal transmission of CWD. Her family history was negative for dementia and other neurologic disorders. Brain magnetic resonance imaging showed mild diffuse volume loss, and electroencephalography demonstrated mild diffuse slowing. Other laboratory studies were unremarkable. Cerebrospinal fluid findings were unremarkable except for a weakly immunostaining 14-3-3 protein band, an indeterminate finding for the diagnosis of prion disease. Genetic testing of the prion protein gene was normal, revealing methionine homozygosity at codon 129. Brain biopsy results were negative for the presence of protease-resistant prion protein but showed definite Alzheimer disease with numerous neuritic plaques and tau-positive neurofibrillary tangles (Figure). Further analysis of brain tissue at the National Prion Disease Pathology Surveillance Center was negative for prion disease by Western blot analysis. Subsequent investigation by the state department of health revealed the patient had worked in an area of the laboratory that conducted necropsies on domestic animals and had never been assigned to the CWD testing laboratory. The Colorado Department of Public Health and Environment could not confirm that the technician had ever worked with deer and elk tissues.
CASE 2 .
This 25-year-old right-handed man had a 4-month history of progressive gait disturbance, myoclonus, hallucinations, slowed cognition, impaired attention, and memory loss. He had hunted deer and elk in a CWD endemic area of southern Wyoming and cooked and ate the field-dressed meat. His family history was significant in that his mother had died of a dementing disease at age 40 years, although there was neither a clinical diagnosis nor an autopsy. Brain magnetic resonance imaging findings were unremarkable, and electroencephalography demonstrated 1-Hz high-amplitude periodic sharp wave complexes. Other laboratory studies had negative results. Testing for the 14-3-3 protein had positive results, but the cerebrospinal fluid was otherwise unremarkable. The diagnosis of Gerstmann-Sträussler-Scheinker syndrome, a familial prion disease, was confirmed with a detailed autopsy examination and referral of the brain to the National Prion Disease Pathology Surveillance Center. Autopsy brain tissue showed the presence of protease-resistant prion protein by Western blot analysis. Genetic evaluation revealed the P102L mutation in the prion protein gene with methionine/valine heterozygosity at codon 129.
Sunday, November 13, 2011
COLORADO CWD CJD TSE PRION REPORTING 2011
Saturday, August 01, 2009
Cases of Early-Onset Sporadic Creutzfeld-Jakob Disease in Michigan Chronic Wasting Disease and Potential Transmission to Humans
Ermias D. Belay,* Ryan A. Maddox,* Elizabeth S. Williams,† Michael W. Miller,‡ Pierluigi Gambetti,§ and Lawrence B. Schonberger*
In 2001, two additional CJD patients 26 and 28 years of age were reported from a single state (Table 2) (34). The patients grew up in adjacent counties and had illness onset within several months of each other. As a result of this fact and their unusually young age, a possible environmental source of infection, including exposure to CWD-infected venison, was considered. One of the patients died after an illness lasting 5–6 months that was characterized by progressive aphasia, memory loss, social withdrawal, vision disturbances, and seizure activity leading to status epilepticus and induced coma. Histopathologic, immunohistochemical, and Western blot testing of brain biopsy and autopsy samples confirmed a CJD diagnosis. The patient’s disease phenotype corresponded to the MM2 sporadic CJD subtype reported by Parchi et al. (35). This patient did not hunt, and family members provided no history of regularly eating venison. The patient may have occasionally eaten venison originating from the Upper Peninsula of Michigan while away from home during his college years. However, ongoing surveillance has not detected CWD in Michigan deer (36).
The second patient died from an illness lasting ˜16 months. The patient’s illness began with behavioral changes, including unusual outbursts of anger and depression. Confusion, memory loss, gait disturbances, incontinence, headaches, and photophobia also developed. Western blot analysis of frozen brain biopsy tissue confirmed a prion disease diagnosis. Immunohistochemical analysis of brain tissue obtained after the patient’s death
showed prion deposition consistent with GSS. Aprion protein gene analysis could not be performed because appropriate samples were lacking. However, prion protein gene analysis of a blood sample from one of the patient’s parents indicated a GSS P102L mutation. The patient did not hunt but may have eaten venison from Michigan once when he was 1–2 years old. The GSS diagnosis greatly reduced the likelihood that the two patients reported from adjacent counties had disease with a common origin. Recently, rare neurologic disorders resulting in the deaths of three men who participated in “wild game feasts” in a cabin owned by one of the decedents created concern about the possible relationship of their illnesses with CWD (Table 2) (37). Two of the patients reportedly died of CJD, and the third died from Pick’s disease. More than 50 persons were identified as possibly participating in these feasts; the three patients were the only participants reported to have died of a degenerative neurologic disorder. Reanalysis of autopsy brain tissues from the three patients at the National Prion Disease Pathology Surveillance Center indicated that two of them had no evidence of a prion disease by immunohistochemical analysis. CJD was confirmed in the third patient, who had clinicopathologic, codon 129, and prion characteristics similar to the most common sporadic CJD subtype (MM1/MV1) (35). This patient participated in the feasts only once, perhaps in the mid-1980s. In addition, the investigation found no evidence that the deer and elk meat served during the feasts originated from the known CWD-endemic areas of Colorado and Wyoming.
In 2003, CJD in two deer and elk hunters (54 and 66 years of age) was reported (38). The report implied that the patients had striking neuropathologic similarities and that their illness may represent a new entity in the spectrum of prion diseases. A third patient (63 years of age), who was also purported to have been a big game hunter, was subsequently reported from the same area. However, none of the three patients were reported to have eaten venison from the CWD-endemic areas of the western United States. The 66- year-old patient hunted most of his life in Washington State. Although information about the 54-year-old patient was limited, there was no evidence that he hunted in CWD-endemic areas. The third patient was not a hunter but ate venison harvested from Pennsylvania and Washington. The neuropathologic changes, Western blot profile, and genotype at codon 129 of the three patients each fit the MM1, VV1, or VV2 sporadic CJD subtype, indicating absence of phenotypic similarity among the cases or atypical neuropathologic features (35). To date, only two nonfamilial CJD cases with a positive history of exposure to venison obtained from the known CWD-endemic areas have been reported. One of the patients was a 61-year-old woman who grew up in an area where this disease is known to be endemic, and she ate venison harvested locally. She died in 2000, and analysis of autopsy brain specimens confirmed that the patient’s CJD phenotype fit the MM1 subtype, with no atypical neuropathologic features. The second patient was a 66-yearold man who was reported to have eaten venison from two deer harvested in a CWD-endemic area. Both deer tested negative for CWD, and the patient’s illness was consistent with the MM1 CJD phenotype.
September 29, 2004
Grand Forks man dies from rare disease
State health officials say lab results are not expected for several weeks on a Grand Forks man who is believed to have died from Creutzfeldt-jakob (croitz-feld juh-COHB') disease, or C-J-D.
It's a rare neurological disease with symptoms similar to mad cow disease.
State Epidemiologist Larry Shireley says North Dakota has seen only a couple of cases of CJD in recent years. Scientists say about 250 people are diagnosed with it in the United States each year.
Shireley says a Cleveland lab that specializes in CJD wants to test tissue samples to make sure 48-old Michael Jose did not have new variant CJD, also known as mad cow disease. Both diseases have some similar symptoms, but no human mad cow cases have been reported in this country.
The testing will be done at the National Prion Disease Pathology Surveillance Center at Case Western Reserve University.
Family members said Jose was never hospitalized and lived at home until the time of his death last Saturday.
Doctor James Hargreaves is an infectious disease specialist at Altru Hospital in Grand Forks. He says it's difficult to know how long Jose had the disease.
February 21, 2003 / 52(07);125-127
Fatal Degenerative Neurologic Illnesses in Men Who Participated in Wild Game Feasts --- Wisconsin, 2002
Creutzfeldt-Jakob disease (CJD) is a fatal neurologic disorder in humans. CJD is one of a group of conditions known as transmissible spongiform encephalopathies (TSEs), or prion diseases, that are believed to be caused by abnormally configured, host-encoded prion proteins that accumulate in the central nervous tissue (1). CJD has an annual incidence of approximately 1 case per million population in the United States (1) and occurs in three forms: sporadic, genetically determined, and acquired by infection. In the latter form, the incubation period is measured typically in years. Recent evidence that prion infection can cross the species barrier between humans and cattle has raised increasing public health concerns about the possible transmission to humans of a TSE among deer and elk known as chronic wasting disease (CWD) (2). During 1993--1999, three men who participated in wild game feasts in northern Wisconsin died of degenerative neurologic illnesses. This report documents the investigation of these deaths, which was initiated in August 2002 and which confirmed the death of only one person from CJD. Although no association between CWD and CJD was found, continued surveillance of both diseases remains important to assess the possible risk for CWD transmission to humans.
Case 1. In December 1992, a Wisconsin man aged 66 years with a history of seizures since 1969 sought treatment for recurring seizures, increasing forgetfulness, and worsening hand tremors. Electroencephalographic (EEG) examination demonstrated focal epileptiform activity and nonspecific diffuse abnormalities, but no specific diagnosis was made. In February 1993, he was hospitalized for increasing confusion, ataxia, and movement tremors of his extremities. A magnetic resonance image (MRI) demonstrated mild, nonspecific enhancement along the inferior parasagittal occipital lobe. A repeat EEG showed bifrontal intermittent, short-interval, periodic sharp waves, suggesting a progressive encephalopathy; a diagnosis of CJD was suspected. The man died later that month; neuropathologic examination of brain tissue during autopsy indicated subacute spongiform encephalopathy, compatible with CJD.
The man was a lifelong hunter who ate venison frequently. He hunted primarily in northern Wisconsin but also at least once in Montana. He hosted wild game feasts at his cabin in northern Wisconsin from 1976 until shortly before his death. Fixed brain tissue obtained during the autopsy was sent for analysis to the National Prion Disease Pathology Surveillance Center (NPDPSC) and reexamined at the institution where the autopsy was conducted. Histopathologic examination did not substantiate the diagnosis of prion disease. In addition, 27 brain tissue sections were negative for prions by immunostaining despite positive antibody reactions against other proteins (controls), which indicated that other epitopes in the tissue samples were preserved.
Case 2. In May 1999, a Minnesota man aged 55 years with no previous history of a neurologic disease sought evaluation and treatment following a 3-month history of progressive difficulty in writing and unsteadiness of gait. A computerized tomography (CT) scan and MRI examination of his head did not indicate any abnormality. In June 1999, he was hospitalized following onset of dementia, speech abnormalities, and myoclonic jerking. An EEG indicated left-hemispheric periodic sharp waves and moderate generalized background slowing; CJD was diagnosed clinically. In July 1999, following worsening symptoms and development of right upper extremity dystonia, the patient died. Neuropathologic evaluation of brain tissue during autopsy demonstrated widespread subcortical spongiform lesions, consistent with CJD.
The man was not a hunter but had a history of eating venison. He made an estimated 12 visits to the cabin where the wild game feasts were held, but he participated in only one feast during the mid-1980s. Sections of fixed and frozen brain tissue obtained during autopsy were analyzed at NPDPSC, and prion disease was confirmed by immunohistochemical and Western blot testing. The Western blot characteristics and prion disease phenotype in this patient were consistent with the most common form of sporadic CJD, classified as M/M (M/V) 1 (3). Subsequent genetic typing confirmed the presence of methionine homozygosity (M/M) at codon 129 of the patient's prion protein gene.
Case 3. In June 1992, a Wisconsin man aged 65 years sought treatment for progressive slowing of speech, worsening memory, and personality changes. By January 1993, his speech was reduced to one-word utterances. Neurologic examination showed a flat affect, decreased reflexes, and apraxia. A CT head scan showed mild atrophy, and an EEG was normal. Pick's disease was diagnosed. By May, he was unable to perform any daily living activities; he died in August 1993. Neuropathologic evaluation of brain tissue during autopsy showed symmetrical frontal lobe cerebral cortical atrophy and mild temporal lobe atrophy. No Pick's bodies or spongiform lesions were observed.
The man had a history of eating venison and participated regularly in wild game feasts held at the cabin owned by patient 1. He was a lifelong hunter and hunted mostly in Wisconsin but also in Wyoming and British Columbia. No game was brought to the wild game feasts from his hunting trips outside of Wisconsin. Examination of fixed brain tissue sent to NPDPSC demonstrated no lesions indicative of CJD, and immunohistochemical testing with antibody to the prion protein did not demonstrate the granular deposits seen in prion diseases.
Wild game feasts consisting of elk, deer, antelope, and other game that occurred at a cabin in northern Wisconsin owned by patient 1 began in 1976 and continued through 2002. These feasts typically involved 10--15 participants and usually occurred on weekends before or during hunting seasons in the fall and occasionally in the spring. Wild game brought to these feasts usually were harvested in Wisconsin, but three men who attended these feasts reported hunting in the western United States and bringing game back to Wisconsin. These activities took place in Colorado (near the towns of Cortez, Trinidad, Collbran, Durango, and Meeker), Wyoming (near the towns of Gilette and Cody), and Montana (near the town of Malta). CWD was not known to be endemic in these areas at the time that these hunting activities took place.
Information was obtained for 45 (85%) of 53 persons who were identified as possibly participating in the wild game feasts; all were male. Information was obtained by direct interview or from family members of decedents. Of the 45 persons, for whom information was obtained, 34 were reported to have attended wild game feasts. Seven of the 34 feast attendees were deceased, including the three patients. None of the four other decedents had a cause of death attributed to or associated with a degenerative neurologic disorder. None of the living participants had any signs or symptoms consistent with a degenerative neurologic disorder.
Reported by: JP Davis, MD, J Kazmierczak, DVM, M Wegner, MD, R Wierzba, Div of Public Health, State of Wisconsin Dept of Health and Family Svcs. P Gambetti, National Prion Disease Pathology Surveillance Center, Case Western Reserve University, Cleveland, Ohio. L Schonberger, MD, R Maddox, MPH, E Belay, MD, Div of Viral and Rickettsial Diseases, National Center for Infectious Diseases; V Hsu, MD, EIS Officer, CDC.
CWD was first described in the United States in the 1960s and classified as a TSE in 1978. Previously localized to a contiguous endemic area in northeastern Colorado and southeast Wyoming, since 2000, CWD has been found in free-ranging deer or elk in Illinois, Nebraska, New Mexico, South Dakota, Wisconsin, and outside the previously known endemic areas of Colorado and Wyoming. CWD has been identified also in captive deer or elk in Colorado, Kansas, Minnesota, Montana, Nebraska, Oklahoma, South Dakota, and Wisconsin (4). Because a variant form of CJD, with specific neuropathologic and molecular characteristics that distinguish it from sporadic CJD, has been associated with eating cattle products infected with a prion that causes bovine spongiform encephalopathy (5), concern has been raised about the possibility that the prion associated with CWD might be transmitted to humans in a similar way.
In this investigation, because only one of the three cases in Wisconsin had neuropathologic confirmation of a prion disease, no association could be made between case participation in the wild game feasts and the development of CJD. Although patient 2 had confirmed CJD, he was unlikely to have eaten CWD-infected venison at these feasts because venison and other game from outside Wisconsin that was served at these feasts did not originate from known CWD-endemic areas, and the man participated in the feasts only once. In addition, the prion disease in this case was consistent with the most common form of sporadic CJD, without apparent unusual neuropathologic or molecular characteristics that might occur if the prion related to CWD had been responsible for the disease.
The findings in this report are subject to at least two limitations. First, not all members participating in wild game feasts could be identified, and not all persons listed as participating could be contacted for interviews. Second, interviews that were conducted required recall of events that occurred up to 25 years ago, limiting the detail or accuracy of events. However, the similar responses obtained from different sources support the accuracy of the investigation findings.
A previous investigation of unusually young CJD patients in whom the transmission of CWD was suspected also did not provide convincing evidence for a causal relationship between CWD and CJD (2). However, limited epidemiologic investigations cannot rule out the possibility that CWD might play a role in causing human illness. Ongoing surveillance of CJD, particularly in states with CWD, is important to assess the risk, if any, for CWD transmission to humans. Because the confirmation of CJD and the detection of a new prion disease require neuropathologic study of brain tissue, physicians are encouraged to contact NPDPSC (http://www.cjdsurveillance.com; telephone, 216-368-0587) to confirm diagnoses of CJD and to distinguish its various subtypes. Because of the known severity of TSEs in humans and the possibility that the CWD prion can affect humans, animals with evidence of CWD should be excluded from the human food or animal feed chains. Hunters and wild venison consumers should follow precautionary guidelines available from the Wisconsin Department of Agriculture, Trade, and Consumer Protection (http://datcp.state.wi.us/core/consumerinfo) to prevent potential exposures to the CWD agent.
Belay E. Transmissible spongiform encephalopathies in humans. Annu Rev Microbiol 1999;53:283--314. Belay E, Gambetti P, Schonberger L, et al. Creutzfeldt-Jakob disease in unusually young patients who consumed venison. Arch Neurol 2001;58:1673--8. Parchi P, Giese A, Capellari S, et al. Classification of sporadic Creutzfeldt-Jakob disease based on molecular and phenotypic analysis of 300 subjects. Ann Neurol 1999;46:224--33. U.S. Department of Agriculture. Positive CWD cases: cumulative through Dec 2002 (including farm herds already depopulated). Available at http://aphisweb.aphis.usda.gov/vs/nahps//cwd/USAMapOfInfectedHerds.jpg. Will RG, Ironside JW, Zeidler M, et al. A new variant of Creutzfeldt-Jakob disease in the UK. Lancet 1996;347:921--5.
CMAJ. 2003 September 2; 169(5): 443.
Wild game feasts and fatal degenerative neurologic illness
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This article has been cited by other articles in PMC.
Background and epidemiology: Creutzfeldt–Jakob disease (CJD) is one of a group of conditions known as prion diseases that are caused by abnormally configured host-encoded prion proteins that accumulate in central nervous system tissue. There are 3 forms: sporadic, genetically determined and, more recently, variant CJD, acquired by infection when the disease crosses the species barrier between humans and cattle.1 A similar prion disease in deer and elk known as chronic wasting disease (CWD) has raised concerns that this prion could also cross species barriers in people who eat wild game.
A report was recently published describing 3 cases of CWD in men who had attended wild game feasts.2 In the first case, a 66-year-old man who had been a lifelong hunter and who ate venison frequently had hosted wild game feasts at his cabin in Montana for 26 years before he died in 1992 of an autopsy-confirmed subacute spongiform encephalopathy compatible with CJD. He had a history of seizures since the age of 43 and had sought treatment for recurring seizures, increasing forgetfulness and worsening hand tremors about a month before he died.
The 2 other cases involved men aged 55 and 65 who died of neurologic illness. These men had histories of eating venison and participating in 1 or more of the first patient's wild game feasts. The younger man presented in 1999 with a 3-month history of difficulty in writing and unsteadiness of gait, followed by dementia, speech abnormalities and myoclonic jerking. Pathologic examination of the brain at autopsy 3 months later revealed widespread subcortical spongiform lesions consistent with CJD. He had visited the first patient's cabin 12 times and had participated in 1 wild game feast.
The older man sought treatment in 1992 for progressive slowing of speech, worsening memory and personality changes. His speech became reduced to single-word utterances, and he died 10 months after initial presentation. He had been a lifelong hunter and had hunted mostly in Wisconsin but also in Wyoming and British Columbia. He had participated regularly in the first patient's wild game feasts. No game had been brought to the wild game feasts from his hunting trips outside of Wisconsin.
Testing of fixed brain tissue from all 3 men revealed no evidence on immunostaining for prions using antibodies to the prion protein in the first and third patients. In the second patient prion disease was confirmed by means of immunohistochemical and Western blot testing. The blot characteristics and prion disease phenotype were consistent with the common form of sporadic CJD, classified as M/M (M/V) 1. Subsequent genetic typing revealed methionine homozygosity (M/M) at codon 129 of the patient's prion protein gene, making it likely that the patient had the most common form of sporadic CJD.
Information obtained for 45 people of 53 identified as possibly participating in the wild game feasts revealed that only 34 had actually attended them. Of the 34, 7 were dead, including the 3 described here; none of the other 4 had died of a degenerative neurologic disorder. None of the living participants had any signs or symptoms consistent with a degenerative neurologic disorder.
Clinical management: Because of the continuing possibility that CWD in deer and elk might be transmissible to humans, physicians should attempt to confirm cases of illness compatible with a transmissible spongiform encephalopathy through pathological examination of brain tissue and by alerting the Canadian CJD surveillance unit (www.hc-sc.gc.ca/pphb-dgspsp/hcai-iamss/cjd-mcj; tel 888 489-2999) or the US National Prion Disease Pathology Surveillance Center (www.cjdsurveillance.com). There is no known treatment for the condition.
Prevention: CWD was first identified in the United States in 1967. In Canada, only 8 cases of CWD have been reported in wild deer, all in Saskatchewan. In the United States, CWD has been found in free-ranging deer and elk in Illinois, Nebraska, New Mexico, South Dakota, Wisconsin, Colorado and Wyoming. Limited epidemiologic investigations to date cannot exclude the possibility that CWD may cause human disease. Because of the severity of the spongiform encephalopathies in humans and the absence of treatment, animals with evidence of CWD should be excluded from human and animal food chains.
John Hoey CMAJ
Doctors study brain tissue of elk hunter / Montana man had symptoms similar to mad cow disease David Perlman
Chronicle Science Editor Published 4:00 a.m., Saturday, September 7, 2002
Researchers at UC San Francisco are analyzing the brain tissue of a Montana elk hunter who died last month with symptoms of a rare human disorder similar to mad cow disease in cattle and the chronic wasting disease that has felled elk and deer in the Midwest and Rocky mountains.
Last October, 50-year-old Gary Padgham of Bozeman first showed the stumbling gait, the dementia and the impaired vision and memory loss that are typical of Creutzfeldt-Jacob disease, known also as CJD. He was taken to a hospital in Seattle where doctors first diagnosed his illness as Huntington's disease, and then as CJD.
Padgham was later moved to Monterey where his family lives, and after he died in August his body was taken to UCSF for a specialized autopsy.
The institution is the nation's primary center for research in the varied brain diseases of humans and animals that are all believed to be caused and transmitted by malformed brain proteins called prions.
CJD is known to be one of the prion diseases, and researchers at UCSF study as many as 20 cases of suspected prion brain diseases a year in an effort to learn more about the invariably fatal malady.
The prions were discovered 20 years ago by Dr. Stanley B. Prusiner, a UCSF neurologist and virologist at UCSF who had been studying several strange brain diseases for a decade and won the 1997 Nobel prize in physiology and medicine for his prion work. Prusiner coined the term prion from the words "proteinaceous infectious particles."
Officials at the UCSF medical center would not discuss Padgham's case specifically Friday because of privacy rules, but a spokeswoman did note that although the disease-causing prions can be transmitted, there has never been a known case of humans contracting CJD from infected elk or deer.
Specialists at the California state health department said the chances are "slim to none" that Padgham could have contracted his disease from eating the meat of the elk he hunted in Montana.
According to the Federal Centers for Disease Control and Prevention, chronic wasting disease has hit captive deer and elk herds in several Midwestern and mountain states, and some wild deer in Wisconsin -- a development that has caused widespread fears among hunters.
In California, the Department of Fish and Game has asked hunters to stop bringing deer and elk parts back from states where the wasting disease has been found, and will seek a regulation banning the import of all high-risk parts, such as brains.
The CDC and other state agencies are also investigating the deaths of Padgham and three other hunters in Montana and Wisconsin. Two of the three died of Creutzfeldt-Jacob disease and one of a different brain disorder called Pick's Disease, where prions are not known to be involved.
Read more: http://www.sfgate.com/health/article/Doctors-study-brain-tissue-of-elk-hunter-2800663.php#ixzz2BwRizpxQ
Observation| October 2001
Creutzfeldt-Jakob Disease in Unusually Young Patients Who Consumed VenisonFREE
Ermias D. Belay, MD; Pierluigi Gambetti, MD; Lawrence B. Schonberger, MD; Piero Parchi, MD; Douglas R. Lyon, MD; Sabina Capellari, MD; Jennifer H. McQuiston, DVM; Kristy Bradley, DVM; Gerrie Dowdle, MSPH; J. Michael Crutcher, MD; Craig R. Nichols, MPA
[+] Author Affiliations
Arch Neurol. 2001;58(10):1673-1678. doi:10-1001/pubs.Arch Neurol.-ISSN-0003-9942-58-10-nob10126.
PATIENT 1 .
In early 1997, a 28-year-old woman was examined several times in an emergency department for abnormal mental status, weakness, and unsteady gait. She also developed ataxia, dyskinesia, and marked dysarthria. The patient's condition gradually deteriorated, and she was admitted to a community hospital in March 1997. On admission, the patient had lethargia, athetoid and choreoform movements, constant lip smacking, possible hallucination, and increased muscle tone. After hospital admission, she developed primitive frontal release signs and episodic focal seizures. The electroencephalogram showed a severely abnormal tracing with diffuse, slow triphasic waves. The computed tomographic scan and magnetic resonance image of the brain did not reveal any abnormality. A brain biopsy performed to evaluate a suspected CJD diagnosis showed only gliosis. The patient died in June 1997, almost 4 months after the onset of illness. .
Histologic examination of brain tissue samples obtained at autopsy showed widespread spongiform degeneration involving the cerebral cortex. The spongiosis was associated with astrogliosis and moderate loss of neurons. The lesions seemed to be more prominent in the frontal lobe and in the entorhinal cortex. The basal ganglia; the thalamus, especially the mediodorsal nucleus; the tectum of the midbrain and pons; the substantia nigra; and the molecular layer of the cerebellar cortex all showed spongiosis and astrogliosis. Immunohistochemical examination for prion protein residues demonstrated a strong and consistent "synaptic" or "punctate" pattern of immunostaining in the cerebral cortex. Rarely, the immunostaining showed a preferential perineuronal distribution that involved both cell body and processes. Analysis of the PRNP indicated a Met/Met homozygosity at the polymorphic codon 129 and absence of genetic mutations. .
The patient's mother indicated that the patient had worked as a cashier at different department stores and a fast food restaurant. She had undergone tonsillar surgery at age 5 years. Her regular diet included consumption of beef, pork, and chicken several times a week. She might have consumed lamb or mutton once every several years. In addition, the patient consumed deer meat between ages 1 and 6 years. The deer were harvested mostly from Maine by the patient's father but occasionally from New Jersey by other family members. The deer carcasses were usually prepared by a custom processor. The patient primarily consumed the deer meat as steaks and ground meat mixed into sauce. At about 6 years of age, the patient had also consumed elk meat provided by a family friend as a gift on 2 different occasions. Although the origin of the elk could not be clearly ascertained, a family member reported that it was likely harvested in Wyoming. The patient was also reported to have occasionally consumed meat from squirrel, bear, and rabbits. No consumption of brain or organ meat from domesticated or game animals was reported. .
PATIENT 2 .
In September 1998, a 29-year-old man was examined at a university hospital for progressive cognitive difficulties. His illness began in May 1998, when he experienced difficulty completing his travel expenses after a routine business trip. The patient became increasingly forgetful, with inability to recall his wife's name, his own home telephone number, and names of long-time family friends. In August 1998 the patient resigned from his job because of the cognitive problems. Subsequently, he developed behavioral problems and difficulties with speech, writing, naming objects, and dressing without assistance. The patient was ambulatory without imbalance but had dysmetria, tremors, and occasional myoclonus. Findings from the initial 2 electroencephalograms, the computed tomographic scan, and cerebral angiographic studies were normal. The magnetic resonance image showed cerebral atrophy without any other abnormalities. Single-photon emission computed tomographic imaging of the brain revealed a nonspecific, asymmetric, diminished perfusion over the left parietal lobe. Results of initial cerebrospinal fluid analysis for 14-3-3 protein were negative in November 1998. A brain biopsy performed in November 1998 showed diffuse spongiform encephalopathy consistent with CJD. The patient died at age 30 years in March 1999, almost 10 months after the onset of illness. .
Histologic examination of the brain tissue samples obtained at autopsy showed prominent spongiform degeneration and gliosis with possible neuronal loss in the cerebral cortex and basal ganglia. In contrast, the cerebellum showed virtually no pathologic changes. The spongiosis often displayed a laminar distribution that affected the deep cortical regions. Neurons that were moderately ballooned were occasionally seen in the cerebral cortex. The pattern of prion protein immunostaining was exclusively "synaptic" in the cerebral cortex and basal ganglia, whereas the cerebellum was virtually unstained. Analysis of the PRNP indicated that the patient was homozygous for valine at the polymorphic codon 129. No PRNP mutation was detected. Immunoblot analysis showed that the PrP-res fragment migrated to 21 kd, corresponding to the prion protein type 1. .
His past occupations included working as a stock boy in a grocery store and recently as a salesperson. The patient had undergone a hernia repair during infancy and tonsillar surgery at approximately 10 years of age. His regular diet included consumption of beef many times a week and pork several times a week. He occasionally ate mutton and cow brain, approximately once every several years. The patient was described as a regular hunter, hunting almost every year since 1985. He was reported to have hunted deer and elk in many areas, almost always in Utah. He did, however, hunt an elk in the southwestern part of Wyoming in 1995 and was part of a team that hunted deer around Williams Lake, British Columbia, in 1989. The patient usually field dressed the carcasses himself and took them to a particular plant for custom processing. In addition, the family has many times received gifts of deer and elk meat from the patient's brother, who regularly hunted in Utah. The family usually ate the deer and elk meat as steak, ground meat, and jerky almost once a month. Moreover, the patient regularly ate liver from deer and elk but not other organ meat, including brain, from any game animals. .
PATIENT 3 .
In December 1998, a 27-year-old man began experiencing difficulty finding his hometown and lapses in memory while performing his duties as a truck driver. During the next month, the patient became increasingly forgetful, constantly asking for directions and instructions on how to operate the truck. He started to exhibit impulsive and impatient behavior, the inability to dress properly, difficulty finding words, and confusion. He also developed myoclonus and sleep disturbances. The electroencephalographic tracing was abnormal but nondiagnostic. The magnetic resonance image of the brain showed diffuse cortical hyperintensity with an unusual but nonspecific pattern. Findings from the cerebrospinal fluid 14-3-3 immunoassay were positive. Histopathologic examination of the cerebral cortical tissue samples obtained at biopsy revealed widespread spongiform degeneration associated with astrogliosis and a possible loss of neurons. Analysis of the PRNP indicated a Met/Val heterozygosity at codon 129 and absence of PRNP mutations. Immunoblot analysis showed that the PrP-res fragment migrated to 21 kd, in the polyacrylamide gel corresponding to the prion protein type 1. The patient died in April 2000 at age 28 years, almost 15 months after the onset of illness. No autopsy was performed. .
His occupations included driving a truck locally and spreading fertilizers. Since 1993 he had also been assisting his father-in-law in raising beef cattle. The patient had no history of surgical procedures. His regular diet included consumption of beef, pork, and chicken several times a week. No consumption of lamb or mutton was reported. The patient was described as an "avid hunter," hunting deer regularly since age 13 years, and frequently harvested at least 1 deer annually. Almost all his deer hunting took place exclusively in 2 very localized areas within 2 counties close to his hometown. The patient usually field dressed the deer carcasses himself and took them to a particular plant for custom processing. During the previous 6 years, the patient and his family had reportedly consumed only ground venison almost once a month. During his childhood, the patient also consumed deer meat harvested by his father. The patient's wife reported no consumption of deer or elk meat originating from either Colorado or Wyoming. However, the custom processing plant where the patient regularly took the deer carcasses for processing also processed approximately 20 elk from Colorado every year. The exact geographic origin in Colorado of these elk could not be ascertained. No consumption of brain or other organs from domesticated or game animals was reported. On the basis of hunter survey data obtained from the local Department of Wildlife Conservation, the patient's hunting practices were typical of other game animal hunters in the area. Analysis of the 1998 hunter licensing data estimated that approximately 24% of families and approximately 17% of households in the state might include a licensed hunter.
Tuesday, 1 May, 2001, 12:28 GMT 13:28 UK
Mad deer disease in Colorado
John Pape from Colorado's Health Department said: "At this point, the answers to these questions are unknown. Because of the BSE experience, it is theoretically possible, and based on that there are some precautions that hunters may want to take."
A farm in the mountains of Nevada may hold a key to the puzzle of Mad Deer disease.
The farm's owner, a cowboy called Jim Koepke, died suddenly from Creutzfeldt Jakob Disease (CJD), an illness very similar to both BSE and the Mad Deer variant.
Brenda, Jim's widow, admits that he loved to hunt. It is possible that he may have died from eating infected deer meat. "I couldn't comprehend that a cowboy in the middle of farming Nevada could get such a horrendous disease," she said. "So I dragged the poor man to many other doctors looking for something that made an ounce of sense."
Jim Koepke was the third deer hunter to die in the last two years from CJD. So far the evidence suggests that it is just coincidence.
But in Colorado, where as many as one in five deer and elk now has the disease, the authorities are urging caution.
Family fears another blood-borne disaster Saturday 27 March 1999 Mark Kennedy The Ottawa Citizen
Doug McEwen is dying of Creutzfeldt-Jakob disease, but plasma products from his blood have been cleared for distribution. Mark Kennedy reports. SALT LAKE CITY - Tracie McEwen reaches over to the dying man in the hospital bed that crowds her small living room. His eyes are closed and he has rarely opened them in recent days. As he moans softly, she strokes his arm and kisses his forehead. "It's OK. Doug, it's OK."
Tracie married Doug exactly four years ago on this date in late March. She marked their anniversary by pouring sparkling cider into cups, making a toast, and lovingly dropping some into Doug's mouth. It is celebration enough that he has survived this long, but it is a bittersweet experience. For he is just a shell of the man he was a few short months ago.
Mr. McEwen is dying of Creutzfeldt-Jakob Disease (CJD), a rare and always fatal neurological disorder that has many different forms. The horrifying condition creeps up on its victims, eating away at the brain, giving it the appearance of a sponge.
Experts say only one in a million people gets the most common strain, known as "classical" CJD, which causes death within a year of symptoms first appearing. The World Health Organization is so concerned about the potential growth of CJD that it is holding an international meeting to discuss how to deal with it.
Doug McEwen's case has spawned an international debate over whether a new, more virulent strain -- dubbed "mad deer disease" -- has appeared in North America.
Governments say Mr. McEwen, 30, has the classical strain, but some scientists question that diagnosis. They say it's possible the Utah man, who was an occasional hunter, is the first known victim of a newer strain contracted by eating deer and elk -- much the same way some in Britain contracted "mad cow disease" from eating infected beef in the 1980s.
In the nearby states of Colorado and Wyoming, there are herds of deer and elk suffering from chronic wasting disease (CWD), a neurological disease in animals associated with CJD. Consumer groups say governments are ignoring what could be the beginning of a worldwide epidemic, but other scientists say there is no basis for such a prediction, which they view as irresponsible and alarmist.
Complicating the situation is the fact that Mr. McEwen has been a blood plasma donor for nearly two years, starting in late 1996. His plasma was sent to the pharmaceutical company Bayer, which fractionated it into various blood products at its plant in Clayton, North Carolina. The products were then shipped to 46 countries around the world, including Canada.
When Mr. McEwen was diagnosed with CJD late last year, Health Canada ordered a temporary quarantine on products containing his plasma. Regulators were alarmed by his age -- classical CJD victims usually get the disease in their 50s and 60s. Only one per cent of them fall into Mr. McEwen's age bracket. Could this be like mad cow disease, regulators asked. After consulting outside experts, the U.S. Food and Drug Administration and Centers for Disease Control, it was determined that Mr. McEwen has the classical form. On Christmas Eve, blood products created with his plasma were cleared for redistribution.
At her apartment in the small town of Kaysville, 50 kilometres north of Salt Lake City, Tracie McEwen has been swamped with calls and visits from U.S. regulators and government scientists.
She believes governments in the U.S. and Canada have made a terrible error by underestimating the potential seriousness of her husband's disease and by prematurely lifting the ban on blood products linked to his plasma.
"I'm not a scientist but I think it's a serious threat," says the 28-year-old, who teaches geography to Grade 9 students. "It's a horrible disease and until they know exactly how it's spread, I think that all the governments are fools to ignore it the way they have. They're fools because they still can't tell me how he got it."
She says her husband, a devout Mormon, was "devastated" at the thought that somehow his disease might be spread through his plasma donations. "Of course, he never would have donated, had we had known," says Tracie, tears welling up in her eyes. "It made me sick when I found out they had put it back on the market. They had it. They had it. They didn't have to use it. That would have been how many less people getting it? And they still put it out. And they still don't know. It's wrong."
Last summer, Doug was a big, strapping man who lived life to its fullest. He fished and hiked, and rode his bicycle in the stunning Utah mountains. He devoted himself to Tracie and their daughters, Sharon, 8, and Rilee, 3. Since then, his weight has dropped from 230 pounds to 130 pounds. He has been trapped in a body that has steadily given up on him.
It started slowly. First, there was the memory loss and the inability to do simple math, then the light tremors. Eventually, came violent seizures as well as the unexplainable outbursts of emotion -- hysterical laughter, sometimes followed by uncontrollable crying. By late January, he could no longer speak in sentences. Three weeks ago, he stopped walking.
Now, he is near death. Tracie, who has cared for all his needs and slept next to him every night on a floor mattress, can only wait for the inevitable.
"This is the worst thing I have seen," she says. "I wouldn't wish it on my worst enemy."
Cowboy Jim Koepke died of CJD
"We encourage hunters to wear gloves when they field-dress carcasses, and at the very least to avoid consuming some of the tissues that we know harbour the chronic wasting disease - things like brain and spinal cord," said Michael Miller, a Colorado vet. What is eerie is how similar the comments of American experts are to those of British government officials during the early years of the Mad Cow crisis. There may be no evidence yet of a threat to humans, but no one is even sure how this disease is transmitted from deer to deer, and the British experience should show us that nothing can be taken for granted.
Generation of a new form of human PrPSc in vitro by inter-species transmission from cervids prions
Marcelo A. Barria1, Glenn C. Telling2, Pierluigi Gambetti3, James A. Mastrianni4 and Claudio Soto1,* 1Mitchell Center for Alzheimer’s disease and related Brain disorders, Dept of Neurology, University of Texas Houston Medical School, Houston, TX 77030, USA 2Dept of Microbiology, Immunology & Molecular Genetics, and Neurology, Sanders Brown Center on Aging, University of Kentucky Medical Center, Lexington, KY, USA 3Institute of Pathology, Case Western Reserve University, Cleveland, OH, USA 4Dept of Neurology, University of Chicago, Chicago, IL, USA. Running Title: Conversion of human PrPC by cervid PrPSc Keywords: Prion / transmissible spongiform encephalopathy / infectivity / misfolded prion protein / prion strains * To whom correspondence should be addressed. University of Texas Houston Medical School, 6431 Fannin St, Houston, TX 77030. Tel 713-5007086; Fax 713-5000667; E-mail Claudio.Soto@uth.tmc.edu The latest version is at http://www.jbc.org/cgi/doi/10.1074/jbc.M110.198465 JBC Papers in Press.
Published on January 4, 2011 as Manuscript M110.198465 Copyright 2011 by The American Society for Biochemistry and Molecular Biology, Inc. 5, Downloaded from www.jbc.org by guest, on November 11, 2012 2
Prion diseases are infectious neurodegenerative disorders affecting humans and animals that result from the conversion of normal prion protein (PrPC) into the misfolded prion protein (PrPSc). Chronic wasting disease (CWD) is a prion disorder of increasing prevalence within the United States that affects a large population of wild and captive deer and elk. Determining the risk of transmission of CWD to humans is of utmost importance, considering that people can be infected by animal prions, resulting in new fatal diseases. To study the possibility that human PrPC can be converted into the misfolded form by CWD PrPSc we performed experiments using the Protein Misfolding Cyclic Amplification (PMCA) technique, which mimic in vitro the process of prion replication. Our results show that cervid PrPSc can induce the conversion of human PrPC, but only after the CWD prion strain has been stabilized by successive passages in vitro or in vivo. Interestingly, the newly generated human PrPSc exhibits a distinct biochemical pattern that differs from any of the currently known forms of human PrPSc. Our results also have profound implications for understanding the mechanisms of prion species barrier and indicate that the transmission barrier is a dynamic process that depend on the strain and moreover the degree of adaptation of the strain. If our findings are corroborated by infectivity assays, they will imply that CWD prions have the potential to infect humans, and that this ability depends on CWD strain adaptation.
Various studies aimed to analyze the transmission of CWD to transgenic mice expressing human PrP have consistently given negative results (9-11), indicating a strong species barrier. This conclusion is consistent with our many failed experiments to attempt converting human PrPC with natural CWD, even after pushing the PMCA conditions (see figure 1). We found successful conversion only after adaptation of the CWD prion strain by successive passages in vitro or in cervid transgenic mice. We are not aware that in any of the transgenic mice studies the inoculum used was a previously stabilized CWD strain. Although, it has been shown that strain stabilization in vitro by PMCA (17;26) and in vivo using experimental rodents (36) has similarities with the strain adaptation process occurring in natural hosts, we cannot rule out that the type of CWD strain adaptation that is required to produce strains transmissible to humans may take much longer time in cervids or not occur at all. An important experiment will be to study transmissibility to humanized transgenic mice of CWD passed experimentally in deer several times. Besides the importance of our results for public health in relation to the putative transmissibility of CWD to humans, our data also illustrate a very important and novel scientific concept related to the mechanism of prion transmission across species barriers. Today the view is that species barrier is mostly controlled by the degree of similarity on the sequence of the prion protein between the host and the infectious material (4). In our study we show that the strain and moreover the stabilization of the strain plays a major role in the inter-species transmission. In our system there is no change on the protein sequence, but yet strain adaptation results in a complete change on prion transmissibility with potentially dramatic consequences. Therefore, our findings lead to a new view of the species barrier that should not be seen as a static process, but rather a dynamic biological phenomenon that can change over time when prion strains mature and evolve. It remains to be investigated if other species barriers also change upon progressive strain adaptation of other prion forms (e.g. the sheep/human barrier).
Our results have far-reaching implications for human health, since they indicate that cervid PrPSc can trigger the conversion of human PrPC into PrPSc, suggesting that CWD might be infectious to humans. Interestingly our findings suggest that unstable strains from CWD affected animals might not be a problem for humans, but upon strain stabilization by successive passages in the wild, this disease might become progressively more transmissible to man.
Generation of a New Form of Human PrPScin Vitro by Interspecies Transmission from Cervid Prions*
Marcelo A. Barria‡, Glenn C. Telling§, Pierluigi Gambetti¶, James A. Mastrianni‖ and Claudio Soto‡,1 + Author Affiliations
From the ‡Mitchell Center for Alzheimer's Disease and Related Brain Disorders, Department of Neurology, University of Texas Medical School at Houston, Houston, Texas 77030, the §Departments of Microbiology, Immunology, and Molecular Genetics and Neurology, Sanders Brown Center on Aging, University of Kentucky Medical Center, Lexington, Kentucky 40506, the ¶Institute of Pathology, Case Western Reserve University, Cleveland, Ohio 44106, and the ‖Department of Neurology, The University of Chicago, Chicago, Illinois 60637 1 To whom correspondence should be addressed: University of Texas Medical School at Houston, 6431 Fannin St., Houston, TX 77030. Tel.: 713-500-7086; Fax: 713-500-0667; E-mail: firstname.lastname@example.org.
Prion diseases are infectious neurodegenerative disorders that affect humans and animals and that result from the conversion of normal prion protein (PrPC) into the misfolded prion protein (PrPSc). Chronic wasting disease (CWD) is a prion disorder of increasing prevalence within the United States that affects a large population of wild and captive deer and elk. Determining the risk of transmission of CWD to humans is of utmost importance, considering that people can be infected by animal prions, resulting in new fatal diseases. To study the possibility that human PrPC can be converted into the misfolded form by CWD PrPSc, we performed experiments using the protein misfolding cyclic amplification technique, which mimics in vitro the process of prion replication. Our results show that cervid PrPSc can induce the conversion of human PrPC but only after the CWD prion strain has been stabilized by successive passages in vitro or in vivo. Interestingly, the newly generated human PrPSc exhibits a distinct biochemical pattern that differs from that of any of the currently known forms of human PrPSc. Our results also have profound implications for understanding the mechanisms of the prion species barrier and indicate that the transmission barrier is a dynamic process that depends on the strain and moreover the degree of adaptation of the strain. If our findings are corroborated by infectivity assays, they will imply that CWD prions have the potential to infect humans and that this ability progressively increases with CWD spreading.
UPDATED DATA ON 2ND CWD STRAIN
Wednesday, September 08, 2010 CWD PRION CONGRESS SEPTEMBER 8-11 2010
PLUS, THE CDC DID NOT PUT THIS WARNING OUT FOR THE WELL BEING OF THE DEER AND ELK ;
Thursday, May 26, 2011
Travel History, Hunting, and Venison Consumption Related to Prion Disease Exposure, 2006-2007 FoodNet Population Survey
Journal of the American Dietetic Association Volume 111, Issue 6 , Pages 858-863, June 2011.
NOR IS THE FDA recalling this CWD positive elk meat for the well being of the dead elk ;
Wednesday, March 18, 2009
Noah's Ark Holding, LLC, Dawson, MN RECALL Elk products contain meat derived from an elk confirmed to have CWD NV, CA, TX, CO, NY, UT, FL, OK RECALLS AND FIELD CORRECTIONS: FOODS CLASS II
Mr R.N. Elmhirst Chairman British Deer Farmers Association Holly Lodge Spencers Lane BerksWell Coventry CV7 7BZ
Dear Mr Elmhirst,
CREUTZFELDT-JAKOB DISEASE (CJD) SURVEILLANCE UNIT REPORT
Thank you for your recent letter concerning the publication of the third annual report from the CJD Surveillance Unit. I am sorry that you are dissatisfied with the way in which this report was published.
The Surveillance Unit is a completely independant outside body and the Department of Health is committed to publishing their reports as soon as they become available. In the circumstances it is not the practice to circulate the report for comment since the findings of the report would not be amended. In future we can ensure that the British Deer Farmers Association receives a copy of the report in advance of publication.
The Chief Medical Officer has undertaken to keep the public fully informed of the results of any research in respect of CJD. This report was entirely the work of the unit and was produced completely independantly of the the Department.
The statistical results reqarding the consumption of venison was put into perspective in the body of the report and was not mentioned at all in the press release. Media attention regarding this report was low key but gave a realistic presentation of the statistical findings of the Unit. This approach to publication was successful in that consumption of venison was highlighted only once by the media ie. in the News at one television proqramme.
I believe that a further statement about the report, or indeed statistical links between CJD and consumption of venison, would increase, and quite possibly give damaging credence, to the whole issue. From the low key media reports of which I am aware it seems unlikely that venison consumption will suffer adversely, if at all.
Friday, November 09, 2012
Chronic Wasting Disease CWD in cervidae and transmission to other species
OR-10: Variably protease-sensitive prionopathy is transmissible in bank voles
Romolo Nonno,1 Michele Di Bari,1 Laura Pirisinu,1 Claudia D’Agostino,1 Stefano Marcon,1 Geraldina Riccardi,1 Gabriele Vaccari,1 Piero Parchi,2 Wenquan Zou,3 Pierluigi Gambetti,3 Umberto Agrimi1 1Istituto Superiore di Sanità; Rome, Italy; 2Dipartimento di Scienze Neurologiche, Università di Bologna; Bologna, Italy; 3Case Western Reserve University; Cleveland, OH USA
Background. Variably protease-sensitive prionopathy (VPSPr) is a recently described “sporadic”neurodegenerative disease involving prion protein aggregation, which has clinical similarities with non-Alzheimer dementias, such as fronto-temporal dementia. Currently, 30 cases of VPSPr have been reported in Europe and USA, of which 19 cases were homozygous for valine at codon 129 of the prion protein (VV), 8 were MV and 3 were MM. A distinctive feature of VPSPr is the electrophoretic pattern of PrPSc after digestion with proteinase K (PK). After PK-treatment, PrP from VPSPr forms a ladder-like electrophoretic pattern similar to that described in GSS cases. The clinical and pathological features of VPSPr raised the question of the correct classification of VPSPr among prion diseases or other forms of neurodegenerative disorders. Here we report preliminary data on the transmissibility and pathological features of VPSPr cases in bank voles.
Materials and Methods. Seven VPSPr cases were inoculated in two genetic lines of bank voles, carrying either methionine or isoleucine at codon 109 of the prion protein (named BvM109 and BvI109, respectively). Among the VPSPr cases selected, 2 were VV at PrP codon 129, 3 were MV and 2 were MM. Clinical diagnosis in voles was confirmed by brain pathological assessment and western blot for PK-resistant PrPSc (PrPres) with mAbs SAF32, SAF84, 12B2 and 9A2.
Results. To date, 2 VPSPr cases (1 MV and 1 MM) gave positive transmission in BvM109. Overall, 3 voles were positive with survival time between 290 and 588 d post inoculation (d.p.i.). All positive voles accumulated PrPres in the form of the typical PrP27–30, which was indistinguishable to that previously observed in BvM109 inoculated with sCJDMM1 cases.
In BvI109, 3 VPSPr cases (2 VV and 1 MM) showed positive transmission until now. Overall, 5 voles were positive with survival time between 281 and 596 d.p.i.. In contrast to what observed in BvM109, all BvI109 showed a GSS-like PrPSc electrophoretic pattern, characterized by low molecular weight PrPres. These PrPres fragments were positive with mAb 9A2 and 12B2, while being negative with SAF32 and SAF84, suggesting that they are cleaved at both the C-terminus and the N-terminus. Second passages are in progress from these first successful transmissions.
Conclusions. Preliminary results from transmission studies in bank voles strongly support the notion that VPSPr is a transmissible prion disease. Interestingly, VPSPr undergoes divergent evolution in the two genetic lines of voles, with sCJD-like features in BvM109 and GSS-like properties in BvI109.
The discovery of previously unrecognized prion diseases in both humans and animals (i.e., Nor98 in small ruminants) demonstrates that the range of prion diseases might be wider than expected and raises crucial questions about the epidemiology and strain properties of these new forms. We are investigating this latter issue by molecular and biological comparison of VPSPr, GSS and Nor98.
Wednesday, March 28, 2012
VARIABLY PROTEASE-SENSITVE PRIONOPATHY IS TRANSMISSIBLE, price of prion poker goes up again $
*** The discovery of previously unrecognized prion diseases in both humans and animals (i.e., Nor98 in small ruminants) demonstrates that the range of prion diseases might be wider than expected and raises crucial questions about the epidemiology and strain properties of these new forms. We are investigating this latter issue by molecular and biological comparison of VPSPr, GSS and Nor98.
AS OF AUGUST 2012 ;
CJD UPDATE USA
1 Listed based on the year of death or, if not available, on year of referral; 2 Cases with suspected prion disease for which brain tissue and/or blood (in familial cases) were submitted; 3 Disease acquired in the United Kingdom; 4 Disease was acquired in the United Kingdom in one case and in Saudi Arabia in the other case; *** 5 Includes 8 cases in which the diagnosis is pending, and 18 inconclusive cases; *** 6 Includes 10 (9 from 2012) cases with type determination pending in which the diagnosis of vCJD has been excluded. *** The Sporadic cases include 16 cases of sporadic Fatal Insomnia (sFI) and 42 cases of Variably Protease-Sensitive Prionopathy (VPSPr) and 2224 cases of sporadic Creutzfeldt-Jakob disease (sCJD).
Tuesday, November 6, 2012
Transmission of New Bovine Prion to Mice, Atypical Scrapie, BSE, and Sporadic CJD, November-December 2012 update