Scrapie Field Trial was developed at Mission, Texas, what if?
Epidemiology of Scrapie in the United States
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Scrapie Field Trial was developed at Mission, Texas, what if?
Scrapie Field Trial was developed at Mission, Texas, on 450 acres of pastureland, part of the former Moore Air Force
EPIDEMIOLOGY OF SCRAPIE IN THE UNITED STATES
Academic Preg
James Hourriganl, Albert Klingsporn2, Edited by » Peast
W. W. Clark3, and M, de Camp4
United States Department of Agriculture,
Animal and Plant Health Inspection Service,
Veterinary Services
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Snip…
Scrapie Field Trial was developed at Mission, Texas, what if?
Scrapie Field Trial was developed at Mission, Texas, on 450 acres of pastureland, part of the former Moore Air Force
EPIDEMIOLOGY OF SCRAPIE IN THE UNITED STATES
Academic Preg
James Hourriganl, Albert Klingsporn2, Edited by » Peast
W. W. Clark3, and M, de Camp4
United States Department of Agriculture,
Animal and Plant Health Inspection Service,
Veterinary Services
snip...
METHODS
A Scrapie Field Trial was developed at Mission, Texas, to provide additional information for the eradication program on the epidemiology of natural scrapie. The Mission Field Trial Station is located on 450 acres of pastureland, part of the former Moore Air Force Base, near Mission,
Texas. It was designed to bring previously exposed, and later also unexposed, sheep or goats to the Station and maintain and breed them under close observation for extended periods
to determine which animals would develop scrapie and define more closely the natural spread and other epidemiological aspects of the disease.
The 547 previously exposed sheep brought to the Mission Station beginning in 1964 were of the Cheviot, Hampshire, Montadale, or Suffolk breeds. They were purchased as field outbreaks occurred, and represented 21 bloodlines in which scrapie had been diagnosed. Upon arrival at the Station, the sheep were maintained on pasture, with supplemental feeding as necessary. The station was divided into 2 areas:
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RESULTS
Table 1 indicated that previously exposed sheep brought to the Station at various times and ages (1 to 89 months old) included 333 Suffolks at risk. Of these, 98 (29%) developed scrapie. This demonstrated the necessity to slaughter such sheep to prevent further Spread of the disease, These pre- viously exposed Suffolks were bred at the Station and produced 446 progeny at risk. Of these 153 (34%) developed scrapie.
Although the minimum and average ages when scnapied were similar for both groups, some of the previously exposed Suffolks brought to the Station developed scrapie when much older--ewes 60 to 142 months old and rams 67 to 102 months old. O£ the 153 Suffolks born at the Station, only 3 were more than 60 months of age (65, 66, and 69 months old).
This difference in age scrapied was attributed to the fact that the Suffolks born at the Station may have been sub- ject to a greater exposure from birth.
It was also observed that when both dam and progeny were scrapied, the progeny nearly always developed clinical disease at a younger age than their respective dam. Thirty- two dams were scrapied at an average of 60 months of age. Forty-six of their progeny developed the disease at an average of 38 months (range 25 to 53 months). Thirty-seven of the 46 progeny were younger than the dam (average 20 months younger, range 2 to 99 months younger). Two were scrapied at the same age as their dams, and 8 were older (average 5 months, range 1 to 13 months older).
++. Although the incidence of scrapie was considerably Greater in the progeny of scrapied compared to free dams, the progeny of either scrapied or free dams manifested scrapie at the typical age and irrespective of the age their respective dams were scrapied. The differences in ages that dams and progeny were scrapied was believed due to difference of exposure, particularly whether they were exposed at an early age,
Table 2 summarized the data on exposed Suffolks and was Prepared so as to show scrapie incidence in the progeny of dams and sires of known Scrapie status. The scrapie incidence in the progeny of Free X Free parents was 25%, progeny of scrapied Sires 39%, and scrapied dams 42%. When both sire and dam were scrapied, the scrapie incidence in 18 Progeny at risk was 78%.
When the scrapie status of the sire was ignored, scrapie incidence in th- progeny of free dams was 34% and in pre y of scrapied da as 62%. When the scrapie status of the dam was ignored, scrapie incidence in the progeny of free sires was 26% and in the progeny of scrapied sires was 452.
Although the scrapie incidence was nearly double in the progeny of scrapied compared to free dams, the latter con- tributed a greater number of scrapied progeny, 116, compared to only 51 cases which had scrapied dams. This was because free dams made a considerably heavier contribution to the progeny at risk4-342 compared to 82. It was felt that in farm flocks a similar situation could exist.
It was possible that free dams could have been mis- classified; however, this was unlikely to have been significant, unless "nonclinical or carrier" dams exist. In this Suffolk group, the ages of 100 free dams of scrapied progeny ranged from 25 to 160 (average 97) months. These free dams did not show clinical signs of scrapie,”and there were no histopathological lesions suggesting scrapie in those which died, If one cannot classify as free, ewes which have reached 97 months (average) and did not develop the disease, from a practical standpoint, it is not possible to classify sheep as free, at least on the basis of clinical signs and histology. The free dams of 50% of the scrapied progeny were more than 100 months of age, averaging 126 months.
Upon arrival at the Mission Station at 3 to 9 months of age, the 140 previously unexposed sheep and goats were placed in infected pastures and corrals and were subjected to con- tact with a succession of natural cases of scrapie in sheep, and eventually also in goats. These animals were bred only within their respective groups and were not crossbred to other breeds of sheep or those brought to the Station from infected flocks or their progeny. The male or female animals mixed freely with animals of their respective sex of the infected Flock and were similarly identified and subjected to similar flock management and diagnostic procedures.
Table 3 indicated that natural scrapie had occurred in 5 of the 140 previously unexposed sheep. One case each occurred in Rambouillet, Targhee, and Hampshire ewes at 88, 89, and 89 months of age and in % Suffolk ewes at 73 and 102 months of age, and 85, 82, 80, 64, and 93 months following initial natural exposure. This represented a natural situation involving lateral spread, under the circumstances involved, when sheep were not exposed when very young. Scrapie was not detected clinicaliy or histologically in any of the dairy or Angora goats brought to the Station. The disease occurred in an average of 27% of the progeny of previously unexposed sheep or goats born at the Station and included cases in progeny of all breeds of sheep or goats taken there, The incidence in the progeny ranged from 14% in Rambouillet sheep to 61% in dairy goats. ~
These data showed that scrapie spread laterally, by contact exposure, from scrapied te previously free animals, but at an apparently lower rate when exposure was first received at the age of 3 to 9 months. These animals were presumed to be susceptible to the disease, as their progeny developed scrapie at rates and ages similar (on the average) to the progeny, pf previously exposed Suffolk sheep born and reared in the same environment.
It was suggested that the progeny of previously unexposed animals developed scrapie at a much higher rate than their parents, and at a younger age, because they were subjected to exposure from birth. The data did not rule out the possibility that the animals born at the Station could have also received the virus from their dams "vertically" prior te, at, or following birth.
Table 4 summarized the scrapie incidence in #he progeny, born at the Station, of previously unexposed dairy goats.
The data were prepared so as to show scrapie incidence in the progeny of dams and sires of known scrapie status.
The 58% incidence in the progeny (24 at risk) of Free X Free parents was more than twice the 25% seen in the Suffolk group (Table 2). Scrapied sires did not increase the incidence in goat progeny (it was 44%); scrapied dams increased the incidence to 71%. When both sire and dam were scrapied the incidence was 89%, with only 9 goat progeny at risk.
When the scrapie status of the sire was ignored, the scrapie incidence in the progeny of free dams was 56% and in the progeny of scrapied dams it was 74%.
Free dams contributed 34 progeny at risk and scrapied dams 31 progeny.
When the scrapie status of the dam was ignored, scrapie incidence was 64% in the progeny of free sires and a similar 66% in the progeny of scrapied sires.
A total of 244 sheep (127 Suffolk, 59 Rambouillet, and 58 Targhee) were removed from scrapie exposure within a few hours of birth or at 4, 9, or 20 months of age and placed in isolation pens. Removal of sheep from exposure at these ages was selected as being representative of usual flock operations when sheep might be sold from an infected flock at weaning, the first fall or the second fall after their birth.
Table 5 reflected the fate of such animals. Four of the 6 scrapied sheep which had been isolated at birth were Suffolks and the 2 older animals were Targhees. The first case in the group isolated at birth was a Targhee, progeny of a ewe that did not develop clinical scrapie. The scrapie incidence in 36 at risk Suffolks removed from exposure at birth was 11%, con- siderably less -“en that expected had these animals remz d in an infected en ment.
Table 6 reflected the status of 51 goats isolated from scrapie exposure at birth, and at 6, 8 to 10, 20, 32 to 59 and 60 to 82 months of age.
None of the goats removed at birth developed scrapie, although all 5 of those alive at 5 years of age had scrapied dams and 1 also had a scrapied sire. The sire of the remaining 4 had sired 7 scrapied progeny. Under such circumstances, had they remained in an infected environment nearly all of these goats would have been expected to develop scrapie. With the exception of the 20 month group, scrapie occurred at an incidence of 25 to 100% in ali other groups and at the expected age. A further observation was that 4 of the progeny of these dairy goats, born and kept apart from any sheep, developed scrapie which suggested that goats were not "dead- end hosts" insofar as scrapie was concerned.
Table 7 recorded the fate of progeny of certain selected scrapied or free Suffolk sheep or dairy goat dams.’
Suffolk ewe G298 was scrapied at 46 months of age. She had twin lambs in 1969 and 1 lamb in 1970. All 3 lambs developed scrapie. Suffolk ewe G27a was scrapied at 39 months. Her lamb born in 1966 was scrapied at 53 months; however, her lambs born in 1967 and 1968 remained free--lived to 102 months of age.
Suffolk ewe G25a died at 131] months of age and was nega- tive clinically and histologically. Mice remained negative following intracerebral inoculation of brain, spleen, and lymph nodes from this ewe. This ewe had 9 progeny at risk, of which 4 developed scrapie and 5 did not. There was no dis- cernible pattern to the cases. In two instances, 1 twin was scrapied and 1 remained free.
Goat B259 was scrapied when 43 months old. All of her 6 progeny at risk developed scrapie.
Goat B14a remained free and died at 101 months of age. Of her 11 progeny at risk, 7 were scrapied and 4 were not.
It was observed at the Station that when scrapied dams had several progeny at risk, 1 or more progeny usually developed the disease. However, many such scrapied dams also had progeny which lived, or are living, considerably beyond the age of their dams and beyond the age animals born at the Station manifested the disease.
It was also observed that individual free dams had free progeny in earlier years followed by scrapied progeny when they were older, or had scrapied progeny when young followed by free progeny when older, or scrapie and free progeny dis- persed throughout the dam's breeding life. The same situation occurred in progeny of scrapied dams; however, the pattern was less irregular due to the smaller number of progeny from each scrapied dam and the higher incidence of scrapie in such progeny. Circumstances prevented breeding all ewes ary year and, thus, many had only 1 progeny at risk. Scrapie developed in 100% of the single progeny at risk of 11 scrapied and 15 free dams. The 26 scrapied progeny were equally divided between ewes and rams.
Table 8 reflected the difference in age scrapied of - sheep brought to the Station compared to the age scrapied of those born there. Although the average age of previously exposed sheep (Suffolks) brought to the Station did not differ greatly from the overall average, several animals brought to the Station developed the disease at quite advanced ages. The previously unexposed scrapied animals brought to the Station were also considerably older than animals born there. Progeny of scrapied dams developed the disease at a slightly younger age than did progeny of free dams. The average age was nearly the same for males and females.
DISCUSSION
snip...see full text;
http://web.archive.org/web/20030513212324/http://www.bseinquiry.gov.uk/files/mb/m08b/tab64.pdf
Scrapie Field Trial was developed at Mission, Texas, on 450 acres of pastureland, part of the former Moore Air Force Base
EPIDEMIOLOGY OF SCRAPIE IN THE UNITED STATES
http://web.archive.org/web/20030513212324/http://www.bseinquiry.gov.uk/files/mb/m08b/tab64.pdf
COLORADO THE ORIGIN OF CHRONIC WASTING DISEASE CWD TSE PRION?
*** 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 abut 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.
http://webarchive.nationalarchives.gov.uk/20080102193705/http://www.bseinquiry.gov.uk/files/mb/m11b/tab01.pdf
The occurrence of CWD must be viewed against the contest of the locations in which it occurred. It was an incidental and unwelcome complication of the respective wildlife research programmes. Despite its subsequent recognition as a new disease of cervids, therefore justifying direct investigation, no specific research funding was forthcoming. The USDA viewed it as a wildlife problem and consequently not their province!” page 26.
https://web.archive.org/web/20060307063531/http://www.bseinquiry.gov.uk/files/mb/m11b/tab01.pdf
Title: Scrapie transmits to white-tailed deer by the oral route and has a molecular profile similar to chronic wasting disease
https://www.ars.usda.gov/research/publications/publication/?seqNo115=317901
''Given the results of this study, current diagnostic techniques would be unlikely to distinguish CWD in sheep from scrapie in sheep if cross-species transmission occurred naturally.''
2021 May 28
Second passage of chronic wasting disease of mule deer to sheep by intracranial inoculation compared to classical scrapie
https://journals.sagepub.com/doi/full/10.1177/10406387211017615
Title: Second passage of chronic wasting disease of mule deer in sheep compared to classical scrapie after intracranial inoculation
https://www.ars.usda.gov/research/publications/publication/?seqNo115=376956
''We inoculated WTD by a natural route of exposure (concurrent oral and intranasal (IN); n=5) with a US scrapie isolate. All scrapie-inoculated deer had evidence of PrPSc accumulation.''
Title: Passage of scrapie to deer results in a new phenotype upon return passage to sheep
https://www.ars.usda.gov/research/publications/publication/?seqNo115=337278
Title: Transmission of the agent of sheep scrapie to deer results in PrPSc with two distinct molecular profiles
In summary, this work demonstrates that WTD are susceptible to the agent of scrapie, two distinct molecular profiles of PrPSc are present in the tissues of affected deer, and inoculum of either profile type readily passes to deer.
http://www.ars.usda.gov/research/publications/publications.htm?SEQ_NO_115=314097
Volume 30, Number 8—August 2024
Research
Scrapie Versus Chronic Wasting Disease in White-Tailed Deer
Zoe J. Lambert1, Jifeng Bian, Eric D. Cassmann, M. Heather West Greenlee, and Justin J. Greenlee
Author affiliations: Oak Ridge Institute for Science and Education, Oak Ridge, Tennessee, USA (Z.J. Lambert); US Department of Agriculture, Ames, Iowa, USA (Z.J. Lambert, J. Bian, E.D. Cassmann, J.J. Greenlee); Iowa State University, Ames (Z.J. Lambert, M.H. West Greenlee) Suggested citation for this article
Abstract
White-tailed deer are susceptible to scrapie (WTD scrapie) after oronasal inoculation with the classical scrapie agent from sheep. Deer affected by WTD scrapie are difficult to differentiate from deer infected with chronic wasting disease (CWD). To assess the transmissibility of the WTD scrapie agent and tissue phenotypes when further passaged in white-tailed deer, we oronasally inoculated wild-type white-tailed deer with WTD scrapie agent. We found that WTD scrapie and CWD agents were generally similar, although some differences were noted. The greatest differences were seen in bioassays of cervidized mice that exhibited significantly longer survival periods when inoculated with WTD scrapie agent than those inoculated with CWD agent. Our findings establish that white-tailed deer are susceptible to WTD scrapie and that the presence of WTD scrapie agent in the lymphoreticular system suggests the handling of suspected cases should be consistent with current CWD guidelines because environmental shedding may occur.
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The potential for zoonoses of cervid-derived PrPSc is still not well understood (6,18,45–47); however, interspecies transmission can increase host range and zoonotic potential (48–50). Therefore, to protect herds and the food supply, suspected cases of WTD scrapie should be handled the same as cases of CWD.
https://wwwnc.cdc.gov/eid/article/30/8/24-0007_article
cwd scrapie pigs oral routes
***> However, at 51 months of incubation or greater, 5 animals were positive by one or more diagnostic methods. Furthermore, positive bioassay results were obtained from all inoculated groups (oral and intracranial; market weight and end of study) suggesting that swine are potential hosts for the agent of scrapie. <***
***> Results: PrPSc was not detected by EIA and IHC in any RPLNs. All tonsils and MLNs were negative by IHC, though the MLN from one pig in the oral <6 month group was positive by EIA. PrPSc was detected by QuIC in at least one of the lymphoid tissues examined in 5/6 pigs in the intracranial <6 months group, 6/7 intracranial >6 months group, 5/6 pigs in the oral <6 months group, and 4/6 oral >6 months group. Overall, the MLN was positive in 14/19 (74%) of samples examined, the RPLN in 8/18(44%), and the tonsil in 10/25 (40%).
***> Conclusions: This study demonstrates that PrPSc accumulates in lymphoid tissues from pigs challenged intracranially or orally with the CWD agent, and can be detected as early as 4 months after challenge. CWD-infected pigs rarely develop clinical disease and if they do, they do so after a long incubation period. This raises the possibility that CWD-infected pigs could shed prions into their environment long before they develop clinical disease. Furthermore, lymphoid tissues from CWD-infected pigs could present a potential source of CWD infectivity in the animal and human food chains.
https://www.ars.usda.gov/research/publications/publication/?seqNo115=353091
https://www.ars.usda.gov/research/project/?accnNo=432011&fy=2017
https://www.ars.usda.gov/research/publications/publication/?seqNo115=337105
The scrapie agent readily transmits between sheep and deer after oronasal exposure. This could confound the identification of CWD strains in deer and the eradication of scrapie from sheep.
https://www.tandfonline.com/doi/full/10.1080/19336896.2019.1615197
2.3.2. New evidence on the zoonotic potential of atypical BSE and atypical scrapie prion strains
PLEASE NOTE;
2.3.2. New evidence on the zoonotic potential of atypical BSE and atypical scrapie prion strains
Olivier Andreoletti, INRA Research Director, Institut National de la Recherche Agronomique (INRA) – École Nationale Vétérinaire de Toulouse (ENVT), invited speaker, presented the results of two recently published scientific articles of interest, of which he is co-author: ‘Radical Change in Zoonotic Abilities of Atypical BSE Prion Strains as Evidenced by Crossing of Sheep Species Barrier in Transgenic Mice’ (MarinMoreno et al., 2020) and ‘The emergence of classical BSE from atypical/Nor98 scrapie’ (Huor et al., 2019).
In the first experimental study, H-type and L-type BSE were inoculated into transgenic mice expressing all three genotypes of the human PRNP at codon 129 and into adapted into ARQ and VRQ transgenic sheep mice. The results showed the alterations of the capacities to cross the human barrier species (mouse model) and emergence of sporadic CJD agents in Hu PrP expressing mice: type 2 sCJD in homozygous TgVal129 VRQ-passaged L-BSE, and type 1 sCJD in homozygous TgVal 129 and TgMet129 VRQ-passaged H-BSE.
https://efsa.onlinelibrary.wiley.com/doi/epdf/10.2903/sp.efsa.2020.EN-1946
WEDNESDAY, JUNE 10, 2020
Radical Change in Zoonotic Abilities of Atypical BSE Prion Strains as Evidenced by Crossing of Sheep Species Barrier in Transgenic Mice
Atypical BSE prions showed a modification in their zoonotic ability after adaptation to sheep-PrP producing agents able to infect TgMet129 and TgVal129, bearing features that make them indistinguishable of sporadic Creutzfeldt-Jakob disease prions.
our results clearly indicate that atypical BSE adaptation to an ovine-PrP sequence could modify the prion agent to potentially infect humans, showing strain features indistinguishable from those of classic sCJD prions, even though they might or might not be different agents.
However, the expanding range of TSE agents displaying the capacity to transmit in human-PrP–expressing hosts warrants the continuation of the ban on meat and bone meal recycling and underscores the ongoing need for active surveillance
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7258450/
***Moreover, sporadic disease has never been observed in breeding colonies or primate research laboratories, most notably among hundreds of animals over several decades of study at the National Institutes of Health25, and in nearly twenty older animals continuously housed in our own facility.***
Even if the prevailing view is that sporadic CJD is due to the spontaneous formation of CJD prions, it remains possible that its apparent sporadic nature may, at least in part, result from our limited capacity to identify an environmental origin.
https://www.nature.com/articles/srep11573
O.05: Transmission of prions to primates after extended silent incubation periods: Implications for BSE and scrapie risk assessment in human populations
Emmanuel Comoy, Jacqueline Mikol, Valerie Durand, Sophie Luccantoni, Evelyne Correia, Nathalie Lescoutra, Capucine Dehen, and Jean-Philippe Deslys Atomic Energy Commission; Fontenay-aux-Roses, France
Prion diseases (PD) are the unique neurodegenerative proteinopathies reputed to be transmissible under field conditions since decades. The transmission of Bovine Spongiform Encephalopathy (BSE) to humans evidenced that an animal PD might be zoonotic under appropriate conditions. Contrarily, in the absence of obvious (epidemiological or experimental) elements supporting a transmission or genetic predispositions, PD, like the other proteinopathies, are reputed to occur spontaneously (atpical animal prion strains, sporadic CJD summing 80% of human prion cases).
Non-human primate models provided the first evidences supporting the transmissibiity of human prion strains and the zoonotic potential of BSE. Among them, cynomolgus macaques brought major information for BSE risk assessment for human health (Chen, 2014), according to their phylogenetic proximity to humans and extended lifetime. We used this model to assess the zoonotic potential of other animal PD from bovine, ovine and cervid origins even after very long silent incubation periods.
*** We recently observed the direct transmission of a natural classical scrapie isolate to macaque after a 10-year silent incubation period,
***with features similar to some reported for human cases of sporadic CJD, albeit requiring fourfold long incubation than BSE. Scrapie, as recently evoked in humanized mice (Cassard, 2014),
***is the third potentially zoonotic PD (with BSE and L-type BSE),
***thus questioning the origin of human sporadic cases.
We will present an updated panorama of our different transmission studies and discuss the implications of such extended incubation periods on risk assessment of animal PD for human health.
===============
***thus questioning the origin of human sporadic cases***
===============
***our findings suggest that possible transmission risk of H-type BSE to sheep and human. Bioassay will be required to determine whether the PMCA products are infectious to these animals.
==============
https://prion2015.files.wordpress.com/2015/05/prion2015abstracts.pdf
***Transmission data also revealed that several scrapie prions propagate in HuPrP-Tg mice with efficiency comparable to that of cattle BSE. While the efficiency of transmission at primary passage was low, subsequent passages resulted in a highly virulent prion disease in both Met129 and Val129 mice.
***Transmission of the different scrapie isolates in these mice leads to the emergence of prion strain phenotypes that showed similar characteristics to those displayed by MM1 or VV2 sCJD prion.
***These results demonstrate that scrapie prions have a zoonotic potential and raise new questions about the possible link between animal and human prions.
http://www.tandfonline.com/doi/abs/10.1080/19336896.2016.1163048?journalCode=kprn20
PRION 2016 TOKYO
Saturday, April 23, 2016
SCRAPIE WS-01: Prion diseases in animals and zoonotic potential 2016
Prion. 10:S15-S21. 2016 ISSN: 1933-6896 printl 1933-690X online
Taylor & Francis
Prion 2016 Animal Prion Disease Workshop Abstracts
WS-01: Prion diseases in animals and zoonotic potential
Transmission of the different scrapie isolates in these mice leads to the emergence of prion strain phenotypes that showed similar characteristics to those displayed by MM1 or VV2 sCJD prion.
These results demonstrate that scrapie prions have a zoonotic potential and raise new questions about the possible link between animal and human prions.
http://www.tandfonline.com/doi/abs/10.1080/19336896.2016.1163048?journalCode=kprn20
Title: Transmission of scrapie prions to primate after an extended silent incubation period)
*** In complement to the recent demonstration that humanized mice are susceptible to scrapie, we report here the first observation of direct transmission of a natural classical scrapie isolate to a macaque after a 10-year incubation period. Neuropathologic examination revealed all of the features of a prion disease: spongiform change, neuronal loss, and accumulation of PrPres throughout the CNS.
*** This observation strengthens the questioning of the harmlessness of scrapie to humans, at a time when protective measures for human and animal health are being dismantled and reduced as c-BSE is considered controlled and being eradicated.
*** Our results underscore the importance of precautionary and protective measures and the necessity for long-term experimental transmission studies to assess the zoonotic potential of other animal prion strains.
http://www.ars.usda.gov/research/publications/publications.htm?SEQ_NO_115=313160
1: J Infect Dis 1980 Aug;142(2):205-8
Oral transmission of kuru, Creutzfeldt-Jakob disease, and scrapie to nonhuman primates.
Gibbs CJ Jr, Amyx HL, Bacote A, Masters CL, Gajdusek DC.
Kuru and Creutzfeldt-Jakob disease of humans and scrapie disease of sheep and goats were transmitted to squirrel monkeys (Saimiri sciureus) that were exposed to the infectious agents only by their nonforced consumption of known infectious tissues. The asymptomatic incubation period in the one monkey exposed to the virus of kuru was 36 months; that in the two monkeys exposed to the virus of Creutzfeldt-Jakob disease was 23 and 27 months, respectively; and that in the two monkeys exposed to the virus of scrapie was 25 and 32 months, respectively. Careful physical examination of the buccal cavities of all of the monkeys failed to reveal signs or oral lesions. One additional monkey similarly exposed to kuru has remained asymptomatic during the 39 months that it has been under observation.
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The successful transmission of kuru, Creutzfeldt-Jakob disease, and scrapie by natural feeding to squirrel monkeys that we have reported provides further grounds for concern that scrapie-infected meat may occasionally give rise in humans to Creutzfeldt-Jakob disease.
PMID: 6997404
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=6997404&dopt=Abstract
Recently the question has again been brought up as to whether scrapie is transmissible to man. This has followed reports that the disease has been transmitted to primates. One particularly lurid speculation (Gajdusek 1977) conjectures that the agents of scrapie, kuru, Creutzfeldt-Jakob disease and transmissible encephalopathy of mink are varieties of a single "virus". The U.S. Department of Agriculture concluded that it could "no longer justify or permit scrapie-blood line and scrapie-exposed sheep and goats to be processed for human or animal food at slaughter or rendering plants" (ARC 84/77)" The problem is emphasised by the finding that some strains of scrapie produce lesions identical to the once which characterise the human dementias"
Whether true or not. the hypothesis that these agents might be transmissible to man raises two considerations. First, the safety of laboratory personnel requires prompt attention. Second, action such as the "scorched meat" policy of USDA makes the solution of the acrapie problem urgent if the sheep industry is not to suffer grievously.
snip...
76/10.12/4.6
http://web.archive.org/web/20010305223125/www.bseinquiry.gov.uk/files/yb/1976/10/12004001.pdf
Nature. 1972 Mar 10;236(5341):73-4.
Transmission of scrapie to the cynomolgus monkey (Macaca fascicularis).
Gibbs CJ Jr, Gajdusek DC.
Nature 236, 73 - 74 (10 March 1972); doi:10.1038/236073a0
Transmission of Scrapie to the Cynomolgus Monkey (Macaca fascicularis)
C. J. GIBBS jun. & D. C. GAJDUSEK
National Institute of Neurological Diseases and Stroke, National Institutes of Health, Bethesda, Maryland
SCRAPIE has been transmitted to the cynomolgus, or crab-eating, monkey (Macaca fascicularis) with an incubation period of more than 5 yr from the time of intracerebral inoculation of scrapie-infected mouse brain. The animal developed a chronic central nervous system degeneration, with ataxia, tremor and myoclonus with associated severe scrapie-like pathology of intensive astroglial hypertrophy and proliferation, neuronal vacuolation and status spongiosus of grey matter. The strain of scrapie virus used was the eighth passage in Swiss mice (NIH) of a Compton strain of scrapie obtained as ninth intracerebral passage of the agent in goat brain, from Dr R. L. Chandler (ARC, Compton, Berkshire).
http://www.nature.com/nature/journal/v236/n5341/abs/236073a0.html
Scrapie Agent (Strain 263K) Can Transmit Disease via the Oral Route after Persistence in Soil over Years
Published: May 9, 2007
https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0000435
WEDNESDAY, DECEMBER 04, 2013
Chronic Wasting Disease CWD and Land Value concerns?
***> This is very likely to have parallels with control efforts for CWD in cervids. <***
Paper
Rapid recontamination of a farm building occurs after attempted prion removal
First published: 19 January 2019 https://doi.org/10.1136/vr.105054
This study clearly demonstrates the difficulty in removing scrapie infectivity from the farm environment. Practical and effective prion decontamination methods are still urgently required for decontamination of scrapie infectivity from farms that have had cases of scrapie and this is particularly relevant for scrapiepositive goatherds, which currently have limited genetic resistance to scrapie within commercial breeds.24 This is very likely to have parallels with control efforts for CWD in cervids.
https://bvajournals.onlinelibrary.wiley.com/doi/abs/10.1136/vr.105054
***>This is very likely to have parallels with control efforts for CWD in cervids.
***> Infectious agent of sheep scrapie may persist in the environment for at least 16 years
***> Nine of these recurrences occurred 14–21 years after culling, apparently as the result of environmental contamination, but outside entry could not always be absolutely excluded.
JOURNAL OF GENERAL VIROLOGY Volume 87, Issue 12
Infectious agent of sheep scrapie may persist in the environment for at least 16 years Free
Gudmundur Georgsson1, Sigurdur Sigurdarson2, Paul Brown3
http://www.microbiologyresearch.org/docserver/fulltext/jgv/87/12/3737.pdf?expires=1540908280&id=id&accname=guest&checksum=ED0572E1E5B272C100A32212A3E3761A
5 or 6 years quarantine is NOT LONG ENOUGH FOR CWD TSE PRION !!!
QUARANTINE NEEDS TO BE 21 YEARS FOR CWD TSE PRION !
FRIDAY, APRIL 30, 2021
Should Property Evaluations Contain Scrapie, CWD, TSE PRION Environmental Contamination of the land?
***> Confidential!!!!
***> As early as 1992-3 there had been long studies conducted on small pastures containing scrapie infected sheep at the sheep research station associated with the Neuropathogenesis Unit in Edinburgh, Scotland. Whether these are documented...I don't know. But personal recounts both heard and recorded in a daily journal indicate that leaving the pastures free and replacing the topsoil completely at least 2 feet of thickness each year for SEVEN years....and then when very clean (proven scrapie free) sheep were placed on these small pastures.... the new sheep also broke out with scrapie and passed it to offspring. I am not sure that TSE contaminated ground could ever be free of the agent!! A very frightening revelation!!!
---end personal email---end...tss
Table 1 indicated that previously exposed sheep brought to the Station at various times and ages (1 to 89 months old) included 333 Suffolks at risk. Of these, 98 (29%) developed scrapie. This demonstrated the necessity to slaughter such sheep to prevent further Spread of the disease, These pre- viously exposed Suffolks were bred at the Station and produced 446 progeny at risk. Of these 153 (34%) developed scrapie.
Although the minimum and average ages when scnapied were similar for both groups, some of the previously exposed Suffolks brought to the Station developed scrapie when much older--ewes 60 to 142 months old and rams 67 to 102 months old. O£ the 153 Suffolks born at the Station, only 3 were more than 60 months of age (65, 66, and 69 months old).
This difference in age scrapied was attributed to the fact that the Suffolks born at the Station may have been sub- ject to a greater exposure from birth.
It was also observed that when both dam and progeny were scrapied, the progeny nearly always developed clinical disease at a younger age than their respective dam. Thirty- two dams were scrapied at an average of 60 months of age. Forty-six of their progeny developed the disease at an average of 38 months (range 25 to 53 months). Thirty-seven of the 46 progeny were younger than the dam (average 20 months younger, range 2 to 99 months younger). Two were scrapied at the same age as their dams, and 8 were older (average 5 months, range 1 to 13 months older).
++. Although the incidence of scrapie was considerably Greater in the progeny of scrapied compared to free dams, the progeny of either scrapied or free dams manifested scrapie at the typical age and irrespective of the age their respective dams were scrapied. The differences in ages that dams and progeny were scrapied was believed due to difference of exposure, particularly whether they were exposed at an early age,
Table 2 summarized the data on exposed Suffolks and was Prepared so as to show scrapie incidence in the progeny of dams and sires of known Scrapie status. The scrapie incidence in the progeny of Free X Free parents was 25%, progeny of scrapied Sires 39%, and scrapied dams 42%. When both sire and dam were scrapied, the scrapie incidence in 18 Progeny at risk was 78%.
When the scrapie status of the sire was ignored, scrapie incidence in th- progeny of free dams was 34% and in pre y of scrapied da as 62%. When the scrapie status of the dam was ignored, scrapie incidence in the progeny of free sires was 26% and in the progeny of scrapied sires was 452.
Although the scrapie incidence was nearly double in the progeny of scrapied compared to free dams, the latter con- tributed a greater number of scrapied progeny, 116, compared to only 51 cases which had scrapied dams. This was because free dams made a considerably heavier contribution to the progeny at risk4-342 compared to 82. It was felt that in farm flocks a similar situation could exist.
It was possible that free dams could have been mis- classified; however, this was unlikely to have been significant, unless "nonclinical or carrier" dams exist. In this Suffolk group, the ages of 100 free dams of scrapied progeny ranged from 25 to 160 (average 97) months. These free dams did not show clinical signs of scrapie,”and there were no histopathological lesions suggesting scrapie in those which died, If one cannot classify as free, ewes which have reached 97 months (average) and did not develop the disease, from a practical standpoint, it is not possible to classify sheep as free, at least on the basis of clinical signs and histology. The free dams of 50% of the scrapied progeny were more than 100 months of age, averaging 126 months.
Upon arrival at the Mission Station at 3 to 9 months of age, the 140 previously unexposed sheep and goats were placed in infected pastures and corrals and were subjected to con- tact with a succession of natural cases of scrapie in sheep, and eventually also in goats. These animals were bred only within their respective groups and were not crossbred to other breeds of sheep or those brought to the Station from infected flocks or their progeny. The male or female animals mixed freely with animals of their respective sex of the infected Flock and were similarly identified and subjected to similar flock management and diagnostic procedures.
Table 3 indicated that natural scrapie had occurred in 5 of the 140 previously unexposed sheep. One case each occurred in Rambouillet, Targhee, and Hampshire ewes at 88, 89, and 89 months of age and in % Suffolk ewes at 73 and 102 months of age, and 85, 82, 80, 64, and 93 months following initial natural exposure. This represented a natural situation involving lateral spread, under the circumstances involved, when sheep were not exposed when very young. Scrapie was not detected clinicaliy or histologically in any of the dairy or Angora goats brought to the Station. The disease occurred in an average of 27% of the progeny of previously unexposed sheep or goats born at the Station and included cases in progeny of all breeds of sheep or goats taken there, The incidence in the progeny ranged from 14% in Rambouillet sheep to 61% in dairy goats. ~
These data showed that scrapie spread laterally, by contact exposure, from scrapied te previously free animals, but at an apparently lower rate when exposure was first received at the age of 3 to 9 months. These animals were presumed to be susceptible to the disease, as their progeny developed scrapie at rates and ages similar (on the average) to the progeny, pf previously exposed Suffolk sheep born and reared in the same environment.
It was suggested that the progeny of previously unexposed animals developed scrapie at a much higher rate than their parents, and at a younger age, because they were subjected to exposure from birth. The data did not rule out the possibility that the animals born at the Station could have also received the virus from their dams "vertically" prior te, at, or following birth.
Table 4 summarized the scrapie incidence in #he progeny, born at the Station, of previously unexposed dairy goats.
The data were prepared so as to show scrapie incidence in the progeny of dams and sires of known scrapie status.
The 58% incidence in the progeny (24 at risk) of Free X Free parents was more than twice the 25% seen in the Suffolk group (Table 2). Scrapied sires did not increase the incidence in goat progeny (it was 44%); scrapied dams increased the incidence to 71%. When both sire and dam were scrapied the incidence was 89%, with only 9 goat progeny at risk.
When the scrapie status of the sire was ignored, the scrapie incidence in the progeny of free dams was 56% and in the progeny of scrapied dams it was 74%.
Free dams contributed 34 progeny at risk and scrapied dams 31 progeny.
When the scrapie status of the dam was ignored, scrapie incidence was 64% in the progeny of free sires and a similar 66% in the progeny of scrapied sires.
A total of 244 sheep (127 Suffolk, 59 Rambouillet, and 58 Targhee) were removed from scrapie exposure within a few hours of birth or at 4, 9, or 20 months of age and placed in isolation pens. Removal of sheep from exposure at these ages was selected as being representative of usual flock operations when sheep might be sold from an infected flock at weaning, the first fall or the second fall after their birth.
Table 5 reflected the fate of such animals. Four of the 6 scrapied sheep which had been isolated at birth were Suffolks and the 2 older animals were Targhees. The first case in the group isolated at birth was a Targhee, progeny of a ewe that did not develop clinical scrapie. The scrapie incidence in 36 at risk Suffolks removed from exposure at birth was 11%, con- siderably less -“en that expected had these animals remz d in an infected en ment.
Table 6 reflected the status of 51 goats isolated from scrapie exposure at birth, and at 6, 8 to 10, 20, 32 to 59 and 60 to 82 months of age.
None of the goats removed at birth developed scrapie, although all 5 of those alive at 5 years of age had scrapied dams and 1 also had a scrapied sire. The sire of the remaining 4 had sired 7 scrapied progeny. Under such circumstances, had they remained in an infected environment nearly all of these goats would have been expected to develop scrapie. With the exception of the 20 month group, scrapie occurred at an incidence of 25 to 100% in ali other groups and at the expected age. A further observation was that 4 of the progeny of these dairy goats, born and kept apart from any sheep, developed scrapie which suggested that goats were not "dead- end hosts" insofar as scrapie was concerned.
Table 7 recorded the fate of progeny of certain selected scrapied or free Suffolk sheep or dairy goat dams.’
Suffolk ewe G298 was scrapied at 46 months of age. She had twin lambs in 1969 and 1 lamb in 1970. All 3 lambs developed scrapie. Suffolk ewe G27a was scrapied at 39 months. Her lamb born in 1966 was scrapied at 53 months; however, her lambs born in 1967 and 1968 remained free--lived to 102 months of age.
Suffolk ewe G25a died at 131] months of age and was nega- tive clinically and histologically. Mice remained negative following intracerebral inoculation of brain, spleen, and lymph nodes from this ewe. This ewe had 9 progeny at risk, of which 4 developed scrapie and 5 did not. There was no dis- cernible pattern to the cases. In two instances, 1 twin was scrapied and 1 remained free.
Goat B259 was scrapied when 43 months old. All of her 6 progeny at risk developed scrapie.
Goat B14a remained free and died at 101 months of age. Of her 11 progeny at risk, 7 were scrapied and 4 were not.
It was observed at the Station that when scrapied dams had several progeny at risk, 1 or more progeny usually developed the disease. However, many such scrapied dams also had progeny which lived, or are living, considerably beyond the age of their dams and beyond the age animals born at the Station manifested the disease.
It was also observed that individual free dams had free progeny in earlier years followed by scrapied progeny when they were older, or had scrapied progeny when young followed by free progeny when older, or scrapie and free progeny dis- persed throughout the dam's breeding life. The same situation occurred in progeny of scrapied dams; however, the pattern was less irregular due to the smaller number of progeny from each scrapied dam and the higher incidence of scrapie in such progeny. Circumstances prevented breeding all ewes ary year and, thus, many had only 1 progeny at risk. Scrapie developed in 100% of the single progeny at risk of 11 scrapied and 15 free dams. The 26 scrapied progeny were equally divided between ewes and rams.
Table 8 reflected the difference in age scrapied of - sheep brought to the Station compared to the age scrapied of those born there. Although the average age of previously exposed sheep (Suffolks) brought to the Station did not differ greatly from the overall average, several animals brought to the Station developed the disease at quite advanced ages. The previously unexposed scrapied animals brought to the Station were also considerably older than animals born there. Progeny of scrapied dams developed the disease at a slightly younger age than did progeny of free dams. The average age was nearly the same for males and females.
DISCUSSION
snip...see full text;
http://web.archive.org/web/20030513212324/http://www.bseinquiry.gov.uk/files/mb/m08b/tab64.pdf
Scrapie Field Trial was developed at Mission, Texas, on 450 acres of pastureland, part of the former Moore Air Force Base
EPIDEMIOLOGY OF SCRAPIE IN THE UNITED STATES
http://web.archive.org/web/20030513212324/http://www.bseinquiry.gov.uk/files/mb/m08b/tab64.pdf
COLORADO THE ORIGIN OF CHRONIC WASTING DISEASE CWD TSE PRION?
*** 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 abut 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.
http://webarchive.nationalarchives.gov.uk/20080102193705/http://www.bseinquiry.gov.uk/files/mb/m11b/tab01.pdf
The occurrence of CWD must be viewed against the contest of the locations in which it occurred. It was an incidental and unwelcome complication of the respective wildlife research programmes. Despite its subsequent recognition as a new disease of cervids, therefore justifying direct investigation, no specific research funding was forthcoming. The USDA viewed it as a wildlife problem and consequently not their province!” page 26.
https://web.archive.org/web/20060307063531/http://www.bseinquiry.gov.uk/files/mb/m11b/tab01.pdf
Title: Scrapie transmits to white-tailed deer by the oral route and has a molecular profile similar to chronic wasting disease
https://www.ars.usda.gov/research/publications/publication/?seqNo115=317901
''Given the results of this study, current diagnostic techniques would be unlikely to distinguish CWD in sheep from scrapie in sheep if cross-species transmission occurred naturally.''
2021 May 28
Second passage of chronic wasting disease of mule deer to sheep by intracranial inoculation compared to classical scrapie
https://journals.sagepub.com/doi/full/10.1177/10406387211017615
Title: Second passage of chronic wasting disease of mule deer in sheep compared to classical scrapie after intracranial inoculation
https://www.ars.usda.gov/research/publications/publication/?seqNo115=376956
''We inoculated WTD by a natural route of exposure (concurrent oral and intranasal (IN); n=5) with a US scrapie isolate. All scrapie-inoculated deer had evidence of PrPSc accumulation.''
Title: Passage of scrapie to deer results in a new phenotype upon return passage to sheep
https://www.ars.usda.gov/research/publications/publication/?seqNo115=337278
Title: Transmission of the agent of sheep scrapie to deer results in PrPSc with two distinct molecular profiles
In summary, this work demonstrates that WTD are susceptible to the agent of scrapie, two distinct molecular profiles of PrPSc are present in the tissues of affected deer, and inoculum of either profile type readily passes to deer.
http://www.ars.usda.gov/research/publications/publications.htm?SEQ_NO_115=314097
Volume 30, Number 8—August 2024
Research
Scrapie Versus Chronic Wasting Disease in White-Tailed Deer
Zoe J. Lambert1, Jifeng Bian, Eric D. Cassmann, M. Heather West Greenlee, and Justin J. Greenlee
Author affiliations: Oak Ridge Institute for Science and Education, Oak Ridge, Tennessee, USA (Z.J. Lambert); US Department of Agriculture, Ames, Iowa, USA (Z.J. Lambert, J. Bian, E.D. Cassmann, J.J. Greenlee); Iowa State University, Ames (Z.J. Lambert, M.H. West Greenlee) Suggested citation for this article
Abstract
White-tailed deer are susceptible to scrapie (WTD scrapie) after oronasal inoculation with the classical scrapie agent from sheep. Deer affected by WTD scrapie are difficult to differentiate from deer infected with chronic wasting disease (CWD). To assess the transmissibility of the WTD scrapie agent and tissue phenotypes when further passaged in white-tailed deer, we oronasally inoculated wild-type white-tailed deer with WTD scrapie agent. We found that WTD scrapie and CWD agents were generally similar, although some differences were noted. The greatest differences were seen in bioassays of cervidized mice that exhibited significantly longer survival periods when inoculated with WTD scrapie agent than those inoculated with CWD agent. Our findings establish that white-tailed deer are susceptible to WTD scrapie and that the presence of WTD scrapie agent in the lymphoreticular system suggests the handling of suspected cases should be consistent with current CWD guidelines because environmental shedding may occur.
snip…
The potential for zoonoses of cervid-derived PrPSc is still not well understood (6,18,45–47); however, interspecies transmission can increase host range and zoonotic potential (48–50). Therefore, to protect herds and the food supply, suspected cases of WTD scrapie should be handled the same as cases of CWD.
https://wwwnc.cdc.gov/eid/article/30/8/24-0007_article
cwd scrapie pigs oral routes
***> However, at 51 months of incubation or greater, 5 animals were positive by one or more diagnostic methods. Furthermore, positive bioassay results were obtained from all inoculated groups (oral and intracranial; market weight and end of study) suggesting that swine are potential hosts for the agent of scrapie. <***
*** Although the current U.S. feed ban is based on keeping tissues from TSE infected cattle from contaminating animal feed, swine rations in the U.S. could contain animal derived components including materials from scrapie infected sheep and goats. These results indicating the susceptibility of pigs to sheep scrapie, coupled with the limitations of the current feed ban, indicates that a revision of the feed ban may be necessary to protect swine production and potentially human health. <***
***> Results: PrPSc was not detected by EIA and IHC in any RPLNs. All tonsils and MLNs were negative by IHC, though the MLN from one pig in the oral <6 month group was positive by EIA. PrPSc was detected by QuIC in at least one of the lymphoid tissues examined in 5/6 pigs in the intracranial <6 months group, 6/7 intracranial >6 months group, 5/6 pigs in the oral <6 months group, and 4/6 oral >6 months group. Overall, the MLN was positive in 14/19 (74%) of samples examined, the RPLN in 8/18(44%), and the tonsil in 10/25 (40%).
***> Conclusions: This study demonstrates that PrPSc accumulates in lymphoid tissues from pigs challenged intracranially or orally with the CWD agent, and can be detected as early as 4 months after challenge. CWD-infected pigs rarely develop clinical disease and if they do, they do so after a long incubation period. This raises the possibility that CWD-infected pigs could shed prions into their environment long before they develop clinical disease. Furthermore, lymphoid tissues from CWD-infected pigs could present a potential source of CWD infectivity in the animal and human food chains.
https://www.ars.usda.gov/research/publications/publication/?seqNo115=353091
https://www.ars.usda.gov/research/project/?accnNo=432011&fy=2017
https://www.ars.usda.gov/research/publications/publication/?seqNo115=337105
The scrapie agent readily transmits between sheep and deer after oronasal exposure. This could confound the identification of CWD strains in deer and the eradication of scrapie from sheep.
https://www.tandfonline.com/doi/full/10.1080/19336896.2019.1615197
2.3.2. New evidence on the zoonotic potential of atypical BSE and atypical scrapie prion strains
PLEASE NOTE;
2.3.2. New evidence on the zoonotic potential of atypical BSE and atypical scrapie prion strains
Olivier Andreoletti, INRA Research Director, Institut National de la Recherche Agronomique (INRA) – École Nationale Vétérinaire de Toulouse (ENVT), invited speaker, presented the results of two recently published scientific articles of interest, of which he is co-author: ‘Radical Change in Zoonotic Abilities of Atypical BSE Prion Strains as Evidenced by Crossing of Sheep Species Barrier in Transgenic Mice’ (MarinMoreno et al., 2020) and ‘The emergence of classical BSE from atypical/Nor98 scrapie’ (Huor et al., 2019).
In the first experimental study, H-type and L-type BSE were inoculated into transgenic mice expressing all three genotypes of the human PRNP at codon 129 and into adapted into ARQ and VRQ transgenic sheep mice. The results showed the alterations of the capacities to cross the human barrier species (mouse model) and emergence of sporadic CJD agents in Hu PrP expressing mice: type 2 sCJD in homozygous TgVal129 VRQ-passaged L-BSE, and type 1 sCJD in homozygous TgVal 129 and TgMet129 VRQ-passaged H-BSE.
https://efsa.onlinelibrary.wiley.com/doi/epdf/10.2903/sp.efsa.2020.EN-1946
WEDNESDAY, JUNE 10, 2020
Radical Change in Zoonotic Abilities of Atypical BSE Prion Strains as Evidenced by Crossing of Sheep Species Barrier in Transgenic Mice
Atypical BSE prions showed a modification in their zoonotic ability after adaptation to sheep-PrP producing agents able to infect TgMet129 and TgVal129, bearing features that make them indistinguishable of sporadic Creutzfeldt-Jakob disease prions.
our results clearly indicate that atypical BSE adaptation to an ovine-PrP sequence could modify the prion agent to potentially infect humans, showing strain features indistinguishable from those of classic sCJD prions, even though they might or might not be different agents.
However, the expanding range of TSE agents displaying the capacity to transmit in human-PrP–expressing hosts warrants the continuation of the ban on meat and bone meal recycling and underscores the ongoing need for active surveillance
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7258450/
***Moreover, sporadic disease has never been observed in breeding colonies or primate research laboratories, most notably among hundreds of animals over several decades of study at the National Institutes of Health25, and in nearly twenty older animals continuously housed in our own facility.***
Even if the prevailing view is that sporadic CJD is due to the spontaneous formation of CJD prions, it remains possible that its apparent sporadic nature may, at least in part, result from our limited capacity to identify an environmental origin.
https://www.nature.com/articles/srep11573
O.05: Transmission of prions to primates after extended silent incubation periods: Implications for BSE and scrapie risk assessment in human populations
Emmanuel Comoy, Jacqueline Mikol, Valerie Durand, Sophie Luccantoni, Evelyne Correia, Nathalie Lescoutra, Capucine Dehen, and Jean-Philippe Deslys Atomic Energy Commission; Fontenay-aux-Roses, France
Prion diseases (PD) are the unique neurodegenerative proteinopathies reputed to be transmissible under field conditions since decades. The transmission of Bovine Spongiform Encephalopathy (BSE) to humans evidenced that an animal PD might be zoonotic under appropriate conditions. Contrarily, in the absence of obvious (epidemiological or experimental) elements supporting a transmission or genetic predispositions, PD, like the other proteinopathies, are reputed to occur spontaneously (atpical animal prion strains, sporadic CJD summing 80% of human prion cases).
Non-human primate models provided the first evidences supporting the transmissibiity of human prion strains and the zoonotic potential of BSE. Among them, cynomolgus macaques brought major information for BSE risk assessment for human health (Chen, 2014), according to their phylogenetic proximity to humans and extended lifetime. We used this model to assess the zoonotic potential of other animal PD from bovine, ovine and cervid origins even after very long silent incubation periods.
*** We recently observed the direct transmission of a natural classical scrapie isolate to macaque after a 10-year silent incubation period,
***with features similar to some reported for human cases of sporadic CJD, albeit requiring fourfold long incubation than BSE. Scrapie, as recently evoked in humanized mice (Cassard, 2014),
***is the third potentially zoonotic PD (with BSE and L-type BSE),
***thus questioning the origin of human sporadic cases.
We will present an updated panorama of our different transmission studies and discuss the implications of such extended incubation periods on risk assessment of animal PD for human health.
===============
***thus questioning the origin of human sporadic cases***
===============
***our findings suggest that possible transmission risk of H-type BSE to sheep and human. Bioassay will be required to determine whether the PMCA products are infectious to these animals.
==============
https://prion2015.files.wordpress.com/2015/05/prion2015abstracts.pdf
***Transmission data also revealed that several scrapie prions propagate in HuPrP-Tg mice with efficiency comparable to that of cattle BSE. While the efficiency of transmission at primary passage was low, subsequent passages resulted in a highly virulent prion disease in both Met129 and Val129 mice.
***Transmission of the different scrapie isolates in these mice leads to the emergence of prion strain phenotypes that showed similar characteristics to those displayed by MM1 or VV2 sCJD prion.
***These results demonstrate that scrapie prions have a zoonotic potential and raise new questions about the possible link between animal and human prions.
http://www.tandfonline.com/doi/abs/10.1080/19336896.2016.1163048?journalCode=kprn20
PRION 2016 TOKYO
Saturday, April 23, 2016
SCRAPIE WS-01: Prion diseases in animals and zoonotic potential 2016
Prion. 10:S15-S21. 2016 ISSN: 1933-6896 printl 1933-690X online
Taylor & Francis
Prion 2016 Animal Prion Disease Workshop Abstracts
WS-01: Prion diseases in animals and zoonotic potential
Transmission of the different scrapie isolates in these mice leads to the emergence of prion strain phenotypes that showed similar characteristics to those displayed by MM1 or VV2 sCJD prion.
These results demonstrate that scrapie prions have a zoonotic potential and raise new questions about the possible link between animal and human prions.
http://www.tandfonline.com/doi/abs/10.1080/19336896.2016.1163048?journalCode=kprn20
Title: Transmission of scrapie prions to primate after an extended silent incubation period)
*** In complement to the recent demonstration that humanized mice are susceptible to scrapie, we report here the first observation of direct transmission of a natural classical scrapie isolate to a macaque after a 10-year incubation period. Neuropathologic examination revealed all of the features of a prion disease: spongiform change, neuronal loss, and accumulation of PrPres throughout the CNS.
*** This observation strengthens the questioning of the harmlessness of scrapie to humans, at a time when protective measures for human and animal health are being dismantled and reduced as c-BSE is considered controlled and being eradicated.
*** Our results underscore the importance of precautionary and protective measures and the necessity for long-term experimental transmission studies to assess the zoonotic potential of other animal prion strains.
http://www.ars.usda.gov/research/publications/publications.htm?SEQ_NO_115=313160
1: J Infect Dis 1980 Aug;142(2):205-8
Oral transmission of kuru, Creutzfeldt-Jakob disease, and scrapie to nonhuman primates.
Gibbs CJ Jr, Amyx HL, Bacote A, Masters CL, Gajdusek DC.
Kuru and Creutzfeldt-Jakob disease of humans and scrapie disease of sheep and goats were transmitted to squirrel monkeys (Saimiri sciureus) that were exposed to the infectious agents only by their nonforced consumption of known infectious tissues. The asymptomatic incubation period in the one monkey exposed to the virus of kuru was 36 months; that in the two monkeys exposed to the virus of Creutzfeldt-Jakob disease was 23 and 27 months, respectively; and that in the two monkeys exposed to the virus of scrapie was 25 and 32 months, respectively. Careful physical examination of the buccal cavities of all of the monkeys failed to reveal signs or oral lesions. One additional monkey similarly exposed to kuru has remained asymptomatic during the 39 months that it has been under observation.
snip...
The successful transmission of kuru, Creutzfeldt-Jakob disease, and scrapie by natural feeding to squirrel monkeys that we have reported provides further grounds for concern that scrapie-infected meat may occasionally give rise in humans to Creutzfeldt-Jakob disease.
PMID: 6997404
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=6997404&dopt=Abstract
Recently the question has again been brought up as to whether scrapie is transmissible to man. This has followed reports that the disease has been transmitted to primates. One particularly lurid speculation (Gajdusek 1977) conjectures that the agents of scrapie, kuru, Creutzfeldt-Jakob disease and transmissible encephalopathy of mink are varieties of a single "virus". The U.S. Department of Agriculture concluded that it could "no longer justify or permit scrapie-blood line and scrapie-exposed sheep and goats to be processed for human or animal food at slaughter or rendering plants" (ARC 84/77)" The problem is emphasised by the finding that some strains of scrapie produce lesions identical to the once which characterise the human dementias"
Whether true or not. the hypothesis that these agents might be transmissible to man raises two considerations. First, the safety of laboratory personnel requires prompt attention. Second, action such as the "scorched meat" policy of USDA makes the solution of the acrapie problem urgent if the sheep industry is not to suffer grievously.
snip...
76/10.12/4.6
http://web.archive.org/web/20010305223125/www.bseinquiry.gov.uk/files/yb/1976/10/12004001.pdf
Nature. 1972 Mar 10;236(5341):73-4.
Transmission of scrapie to the cynomolgus monkey (Macaca fascicularis).
Gibbs CJ Jr, Gajdusek DC.
Nature 236, 73 - 74 (10 March 1972); doi:10.1038/236073a0
Transmission of Scrapie to the Cynomolgus Monkey (Macaca fascicularis)
C. J. GIBBS jun. & D. C. GAJDUSEK
National Institute of Neurological Diseases and Stroke, National Institutes of Health, Bethesda, Maryland
SCRAPIE has been transmitted to the cynomolgus, or crab-eating, monkey (Macaca fascicularis) with an incubation period of more than 5 yr from the time of intracerebral inoculation of scrapie-infected mouse brain. The animal developed a chronic central nervous system degeneration, with ataxia, tremor and myoclonus with associated severe scrapie-like pathology of intensive astroglial hypertrophy and proliferation, neuronal vacuolation and status spongiosus of grey matter. The strain of scrapie virus used was the eighth passage in Swiss mice (NIH) of a Compton strain of scrapie obtained as ninth intracerebral passage of the agent in goat brain, from Dr R. L. Chandler (ARC, Compton, Berkshire).
http://www.nature.com/nature/journal/v236/n5341/abs/236073a0.html
Scrapie Agent (Strain 263K) Can Transmit Disease via the Oral Route after Persistence in Soil over Years
Published: May 9, 2007
https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0000435
WEDNESDAY, DECEMBER 04, 2013
Chronic Wasting Disease CWD and Land Value concerns?
***> This is very likely to have parallels with control efforts for CWD in cervids. <***
Paper
Rapid recontamination of a farm building occurs after attempted prion removal
First published: 19 January 2019 https://doi.org/10.1136/vr.105054
This study clearly demonstrates the difficulty in removing scrapie infectivity from the farm environment. Practical and effective prion decontamination methods are still urgently required for decontamination of scrapie infectivity from farms that have had cases of scrapie and this is particularly relevant for scrapiepositive goatherds, which currently have limited genetic resistance to scrapie within commercial breeds.24 This is very likely to have parallels with control efforts for CWD in cervids.
https://bvajournals.onlinelibrary.wiley.com/doi/abs/10.1136/vr.105054
***>This is very likely to have parallels with control efforts for CWD in cervids.
***> Infectious agent of sheep scrapie may persist in the environment for at least 16 years
***> Nine of these recurrences occurred 14–21 years after culling, apparently as the result of environmental contamination, but outside entry could not always be absolutely excluded.
JOURNAL OF GENERAL VIROLOGY Volume 87, Issue 12
Infectious agent of sheep scrapie may persist in the environment for at least 16 years Free
Gudmundur Georgsson1, Sigurdur Sigurdarson2, Paul Brown3
http://www.microbiologyresearch.org/docserver/fulltext/jgv/87/12/3737.pdf?expires=1540908280&id=id&accname=guest&checksum=ED0572E1E5B272C100A32212A3E3761A
5 or 6 years quarantine is NOT LONG ENOUGH FOR CWD TSE PRION !!!
QUARANTINE NEEDS TO BE 21 YEARS FOR CWD TSE PRION !
FRIDAY, APRIL 30, 2021
Should Property Evaluations Contain Scrapie, CWD, TSE PRION Environmental Contamination of the land?
***> Confidential!!!!
***> As early as 1992-3 there had been long studies conducted on small pastures containing scrapie infected sheep at the sheep research station associated with the Neuropathogenesis Unit in Edinburgh, Scotland. Whether these are documented...I don't know. But personal recounts both heard and recorded in a daily journal indicate that leaving the pastures free and replacing the topsoil completely at least 2 feet of thickness each year for SEVEN years....and then when very clean (proven scrapie free) sheep were placed on these small pastures.... the new sheep also broke out with scrapie and passed it to offspring. I am not sure that TSE contaminated ground could ever be free of the agent!! A very frightening revelation!!!
---end personal email---end...tss
SUNDAY, JANUARY 19, 2025
ON THE ORIGIN OF TME AND BSE, WHAT IF?
https://transmissiblespongiformencephalopathy.blogspot.com/2025/01/on-origin-of-tme-and-bse-what-if.html
ON THE ORIGIN OF TME AND BSE, WHAT IF?
https://transmissiblespongiformencephalopathy.blogspot.com/2025/01/on-origin-of-tme-and-bse-what-if.html
Terry S. Singeltary Sr.
posted by Terry S. Singeltary Sr. at
1:47 PM
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