Monday, January 08, 2024

CWD TSE Prion, using canine and feline species as a tool, as scavengers to contain disease, is a bad idea, here's why

CWD TSE Prion, using canine and feline species as a tool, as scavengers to contain disease, is a bad idea, here's why

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).

References

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 26, 2012 

CANINE SPONGIFORM ENCEPHALOPATHY: A NEW FORM OF ANIMAL PRION DISEASE 


2013 

Strain characteristics of the in vitro-adapted rabbit and dog BSE agent remained invariable with respect to the original cattle BSE prion, suggesting that the naturally low susceptibility of rabbits and dogs to prion infections should not alter their zoonotic potential if these animals became infected with BSE. 

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Neurobiology of Disease Bovine Spongiform Encephalopathy Induces Misfolding of Alleged Prion-Resistant Species Cellular Prion Protein without Altering Its Pathobiological Features 

Enric Vidal3, Natalia Fernández-Borges1, Belén Pintado4, Montserrat Ordóñez3, Mercedes Márquez6, Dolors Fondevila5,6, Juan María Torres7, Martí Pumarola5,6, and Joaquín Castilla1,2 + Author Affiliations 1CIC bioGUNE, 48160 Derio, Bizkaia, Spain, 2IKERBASQUE, Basque Foundation for Science, 48011 Bilbao, Bizkaia, Spain, 3Centre de Recerca en Sanitat Animal, Campus de la Universitat Autònoma de Barcelona (UAB)-IRTA, 08193 Bellaterra, Barcelona, Spain, 4Centro Nacional de Biotecnología, Campus de Cantoblanco, 28049 Cantoblanco, Madrid, Spain, 5Department of Animal Medicine and Surgery, Veterinary Faculty, UAB, 08193 Bellaterra (Cerdanyola del Vallès), Barcelona, Spain, 6Murine Pathology Unit, Centre de Biotecnologia Animal i Teràpia Gènica, UAB, 08193 Bellaterra (Cerdanyola del Vallès), Barcelona, Spain, and 7Centro de Investigación en Sanidad Animal-Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, 28130 Valdeolmos, Madrid, Spain Author contributions: E.V., N.F.-B., and J.C. designed research; E.V., N.F.-B., B.P., M.O., M.M., D.F., and J.C. performed research; E.V., N.F.-B., B.P., and J.C. contributed unpublished reagents/analytic tools; E.V., N.F.-B., B.P., M.O., M.M., D.F., J.M.T., M.P., and J.C. analyzed data; E.V. and J.C. wrote the paper. 

Abstract Bovine spongiform encephalopathy (BSE) prions were responsible for an unforeseen epizootic in cattle which had a vast social, economic, and public health impact. This was primarily because BSE prions were found to be transmissible to humans. Other species were also susceptible to BSE either by natural infection (e.g., felids, caprids) or in experimental settings (e.g., sheep, mice). However, certain species closely related to humans, such as canids and leporids, were apparently resistant to BSE. In vitro prion amplification techniques (saPMCA) were used to successfully misfold the cellular prion protein (PrPc) of these allegedly resistant species into a BSE-type prion protein. The biochemical and biological properties of the new prions generated in vitro after seeding rabbit and dog brain homogenates with classical BSE were studied. Pathobiological features of the resultant prion strains were determined after their inoculation into transgenic mice expressing bovine and human PrPC. Strain characteristics of the in vitro-adapted rabbit and dog BSE agent remained invariable with respect to the original cattle BSE prion, suggesting that the naturally low susceptibility of rabbits and dogs to prion infections should not alter their zoonotic potential if these animals became infected with BSE. This study provides a sound basis for risk assessment regarding prion diseases in purportedly resistant species. 

Received January 18, 2013. Revision received March 7, 2013. Accepted March 23, 2013. Copyright © 2013 the authors 0270-6474/13/337778-09$15.00/0 


Friday, March 8, 2013 

Dogs may have been used to make Petfood and animal feed



 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: cjohnson@svm.vetmed.wisc.edu 

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. 


''It has been reported (8) the ability of chronic wasting disease (CWD) -infected brain material to pass through the gastrointestinal tract of coyotes (Canis latrans) following oral ingestion, and be infectious, demonstrating that mammalian scavengers could contribute to the translocation and contamination of CWD in the environment.'' 

Consumption of Big Game Remains by Scavengers: A Potential Risk as Regards Disease Transmission in Central Spain

Ricardo Carrasco-Garcia Patricia Barroso Javier Perez-Olivares Vidal Montoro Joaquín Vicente* SaBio group, Instituto de Investigación en Recursos Cinegéticos (CSIC-UCLM-JCCM), Ciudad Real, Spain 

Understanding the role that facultative scavenger species may play in spreading infectious pathogens, and even becoming reservoirs for humans, domestic and wild ungulates or, on the contrary, preventing the spread of disease, requires a prior understanding of the pattern of carrion scavenging in specific scenarios. The objectives of this paper are (i) to describe the guild of vertebrate scavengers and (ii) to study the species-specific, habitat, and management-related factors involved in the usage of gut piles in South Central Spain (SCS), a tuberculosis (TB) endemic area. We used camera trapping at 18 hunting piles on seven hunting estates. A total of eight bird and five mammal taxa were detected at the remains of hunting piles. The most frequently detected species in terms of number of gut piles visited (78%) and scavenged (61%) was the red fox Vulpes vulpes, followed by the griffon vulture Gyps fulvus (56% as regards both presence and scavenging) and the raven Corvus corax (61 and 39% as regards presence and scavenging, respectively). We evidenced that griffon vultures accounted for most of the scavenging activity in open habitats, while facultative mammal scavengers, red fox, and wild boar Sus scrofa made the highest contribution to scavenging in vegetation-covered habitats. In the case of wild boar, the gut piles deposited during the evening and night favored higher rates of scavenging, while the opposite pattern was observed for griffons. Overall, our findings suggest that when disposing of hunting remains in areas of risk as regards disease transmission it is particularly important to consider the access that facultative mammals, and especially wild boar, have to material, while the presence of the resource needs to be safeguarded to protect specialist scavengers of conservation value. These results are of particular relevance in the case of wild boar in the current context of re-emerging TB and emerging African swine fever (ASF) in Europe.


Research Papers

CWD prions remain infectious after passage through the digestive system of coyotes (Canis latrans)

Tracy A Nichols, Justin W Fischer, Terry R Spraker, Qingzhong Kong & Kurt C VerCauteren Pages 367-375 | Received 07 Jul 2015, Accepted 18 Aug 2015, Accepted author version posted online: 04 Dec 2015, Published online: 04 Dec 2015 Download citation https://doi.org/10.1080/19336896.2015.1086061

ABSTRACT

Chronic wasting disease (CWD) is a geographically expanding prion disease of wild and captive cervids in North America. Disease can be transmitted directly, animal to animal, or indirectly via the environment. CWD contamination can occur residually in the environment via soil, water, and forage following deposition of bodily fluids such as urine, saliva, and feces, or by the decomposition of carcasses. Recent work has indicated that plants may even take up prions into the stems and leaves. When a carcass or gut pile is present in the environment, a large number of avian and mammalian species visit and consume the carrion. Additionally, predators like coyotes, likely select for disease-compromised cervids. Natural cross-species CWD transmission has not been documented, however, passage of infectious prion material has been observed in the feces of crows. In this study we evaluated the ability of CWD-infected brain material to pass through the gastrointestinal tract of coyotes (Canis latrans) following oral ingestion, and be infectious in a cervidized transgenic mouse model. Results from this study indicate that coyotes can pass infectious prions via their feces for at least 3 days post ingestion, demonstrating that mammalian scavengers could contribute to the translocation and contamination of CWD in the environment.

Keywords: chronic wasting disease, coyotes, environmental contamination, feces, prions, scavengers, transmission

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Discussion The continued spread of CWD is of concern to the health of both wild and captive cervid populations. Indirect transmission through the environment has been demonstrated in captive animals living in paddocks where CWD-positive animals had lived,Citation3 and is a particular challenge due to the long persistence of CWD within the environment.Citation7,28 Infectious material can be deposited in the environment by the decay of infected carcasses, from urine, feces, and saliva,Citation5,6,29 and the spread of infected material may be aided by scavengers and predators. In this study we illustrated the ability of coyotes to pass infectivity in their feces after the ingestion of CWD-infected brain homogenate.

Coyotes have the ability to travel significant distances. This distance, however, is based upon social structure, which is generally placed in 2 categories; resident or transient.Citation30 Resident animals are those that utilize a specific territory and are comprised of a mated pair and sometimes pups from a previous year, while transient animals are individuals that are nomadic, more commonly male, and have no affinity for a specific territory.Citation30 In a study evaluating the range of coyotes in southern Colorado, transient animals, which represented 22% of the population, ranged over 106.5 ± 27 km2, versus resident groups which ranged over 11.3 ± 5.8 km.Citation2,30 Transient coyotes are therefore provided an opportunity to translocate disease to previously CWD-negative localities.

Control coyotes readily consumed the homogenized elk brain. Of the treatment coyotes, which were moved indoors 2 days prior to the initiation of the study, only one (#135) immediately ate the brain homogenate. The other coyotes required supplementation with diced, raw chicken, or fish-flavored soft cat food. Although the numbers are too small to come to any definitive conclusions, it is interesting to note that the coyote that ingested the brain homogenate without chicken or cat food supplementation did not appear to transfer infectivity to any of the mice in the bioassay. Neither age nor sex appeared to have any effect on fecal shedding. However, it is possible that individual variation within the stomach environment, such as pH and flora could have influenced the passage of the infectious prions through the gastrointestinal tract.

Our experimental design was based on detection of CWD in coyote feces by PMCA prior to initiation of the bioassay. PMCA was able to repeatedly detect the presence of proteinase K-resistant prions signal in feces from DPI 1, so the bioassay was designed to evaluate feces for 2 days following, to account for any uncertainty in prion detection in feces. Results from the bioassay showed transmission of disease to 2/4 mouse groups in DPI 3, suggesting that infectivity may continue to be present in the feces more than 3 days after ingestion. We were unable to go back and increase the bioassay to include DPI 4 and 5, due to logistical reasons.

The 50 mL oral dose ingested by coyotes in this study was comprised solely of infected brain tissue and represented a high dose. In the wild, coyotes would opportunistically consume a wide variety of tissues from a kill or scavenged deer or elk carcass, likely making their actual ingested infective dose much smaller. This study was not designed to mimic a naturally consumed dose of CWD, but rather as a proof of concept to determine if infectivity could pass into coyote feces. The passage of disease in feces is a common route of translocation for many viral, bacterial and parasitic diseases.

The results of this bioassay indicate that infectious CWD prions are able to be passed in the feces of coyotes fed infected elk brain homogenate for at least 3 DPI, making them a potential vector for CWD prion transport and contamination within the environment.


PO-081: Chronic wasting disease in the cat— Similarities to feline spongiform encephalopathy (FSE) 

Davis Seelig, Amy Nalls, Maryanne Flasik, Victoria Frank, Candace Mathiason, Edward Hoover Colorado State University; Fort Collins, CO USA 

Background and Introduction. Chronic wasting disease (CWD) is an efficiently transmitted prion disease of cervids with an as yet to be fully defined host range. Moreover, the risk that CWD poses to feline predators and scavangers, through crossspecies consumption and subsequent transmission, is unknown. Previous and ongoing studies in our laboratory evaluating the susceptibility of domestic cats (Felis catus) to CWD (Mathiason et. al., NeuroPrion 2011, Nalls et. al., NeuroPrion 2012) have documented the susceptibility of domestic cats to CWD following intracerebral (IC) inoculation. However, many of the pathologic features of feline-adapted CWD, including the neural and systemic patterns of PrPCWD accumulation and neuropathology, remain unknown. The chief objectives of this work were: 

(1) to design a sensitive, enhanced immunohistochemical (E-IHC) protocol for the detection of CWD prions (PrPCWD) in feline tissues; 

(2) to document the systemic distribution of PrPCWD in CWD-infected cats through E-IHC; 

(3) to utilize single and multiple-label immunostaining and laser scanning confocal microscopy (LSCM) to provide insights into the subcellular patterns of PrPCWD accumulation and neuropathologic features of CWD-infected cats; and 

(4) to compare feline CWD to the other known feline TSE 

Materials and Methods. Periodate-lysine-paraformaldehyde (PLP)-fixed, paraffin-embedded (PLP-PE) from terminal, IC-inoculated (n = 9) and sham-inoculated (n = 2), 1st and 2nd passage, CWD-infected cats were examined by E-IHC for the presence of PrPCWD and its association with markers of cell phenotype and organelles. Results. The most sensitive E-IHC technique for the detection of PrPCWD in feline tissues incorporated a combination of slide pretreatment with proteinase-K (PK) in concert with tyramide signal amplification (TSA). With this protocol, we identified PrPCWD deposits throughout the CNS, which, in the 1st passage cats was primarily restricted to the obex, but increased in distribution and severity upon 2nd passage to include a number of midbrain nuclei, cortical gray matter, the thalamus and hypothalamus, and the hippocampus. Peripheral PrPCWD deposits were detected only in the 2nd passage cats, and included the enteric nervous system, the Peyer’s patches, and the retropharyngeal and mesenteric lymph nodes. PrPCWD was not detected in the sham-inoculated cats. Moreover, using multi-label analysis, intracellular PrPCWD aggregates were seen in association with neurofilament heavy chain (NFH)-positive neurons and GFAP-positive astrocytes. In addition, large aggregates of intracellular PrPCWD were identified within LAMP1-positive lysosomes. Conclusions. Feline PrPCWD is present in CNS neurons, astrocytes and LAMP-1-positive lysosomes. The morphologic overlap between the PrPCWD deposits in feline CWD and BSE-origin feline spongiform encephalopathy (FSE), implicates the importance of the host as a key determinant in the development of prion neuropathology and suggest a signature for detection of potential spontaneous feline prion disease. 

http://www.landesbioscience.com/journals/prion/04-Prion6-2-Pathogenesis-and-pathology.pdf 


PO-041: Susceptibility of domestic cats to CWD infection 

Amy Nalls, Jeanette Hayes-Klug, Kelly Anderson, Davis Seelig, Kevin Carnes, Susan Kraft, Edward Hoover, Candace Mathiason Colorado State University; Fort Collins, CO USA 

Domestic and non-domestic cats have been shown to be susceptible to feline spongiform encephalopathy (FSE); very likely due to consumption of bovine spongiform encephalopathy (BSE) contaminated meat. Because domestic and free-ranging nondomestic felids scavenge cervid carcasses, including those in areas affected by chronic wasting disease (CWD), we evaluated the susceptibility of domestic cats to CWD infection experimentally. Groups of n = 5 cats each were inoculated either intracerebrally (IC) or orally (PO) with CWD-infected deer brain homogenate. Between 40 and 43 months two IC-inoculated cats developed slowly progressive symptoms including weight loss, anorexia, polydipsia, patterned motor behaviors, and ataxia”’ultimately mandating euthanasia. PrPCWD was detected in the brains of these animals by western blot, immunohistochemistry (IHC), and quaking-induced conversion (RT-QuIC) assays. No clinical signs of TSE were detected in the remaining primary passage cats at 86 months pi. Feline-adapted CWD (FelCWD) was sub-passaged into groups (n = 4 or 5) of cats by IC, PO, and IP/SQ routes. All 5 IC inoculated cats developed symptoms of disease 20–24 months pi (approximately half the incubation period of primary passage). Additional symptoms in these animals included increasing aggressiveness and hyper responsiveness. FelCWD was demonstrated in the brains of all the affected cats by western blot and IHC. Currently, 3 of 4 IP/SQ, and 1 of 4 PO inoculated cats have developed abnormal behavior patterns consistent with the early stage of feline CWD. Magnetic resonance imaging (MRI) has been performed on 11 cats (6 clinically ill, 2 asymptomatic, and 3 age-matched negative controls). 

Abnormalities were detected in 4 of 6 clinically ill cats and included multifocal signal changes consistent with inflammation, ventricular size increases, more prominent sulci, and white matter tract cavitation. 

These results demonstrate that CWD can be transmitted and adapted to the domestic cat, and raise the potential for cervid-to-feline transmission in nature. 


MONDAY, AUGUST 8, 2011 

Susceptibility of Domestic Cats to CWD Infection Oral.29: Susceptibility of Domestic Cats to CWD Infection


11. During the period we also collated information on cases of SE that occurred in wild animals at or from other zoos in the British Isles. The total number of cases of which I was aware in June 1996, when I presented a review on occurrence of spongiform encephalopathies in zoo animals (at the Royal College of Pathologists’ Symposium on Transmitting prions: BSE, CJD, and other TSEs, The Royal Society, London, 4th July 1996), was 25, involving 10 species. The animals involved were all from the families Bovidae and Felidae, and comprised: 1 Nyala Tragelaphus angasi, 5 Eland Taurotragus oryx, 6 greater kudu Tragelaphus strepsiceros, 1 Gemsbok Oryx gazella, 1 Arabian oryx Oryx leucoryx, 1 Scimitar-horned oryx Oryx dammah, 

4 Cheetah Acinonyx jubatus, 

3 Puma Felis concolor 

2 Ocelot Felis pardalis, and 

1 Tiger Panthera tigris. 

(A spongiform encephalopathy, which was thought probably to have a different aetiology, had also been reported in 3 ostriches Struthio camelus in Germany). This list did not include cases of BSE in domesticated species in zoos (ie BSE in Ankole or other cattle, or SEs, assumed to be scrapie, in mouflon sheep Ovis musimon). 

http://www.bseinquiry.gov.uk/files/ws/s324.pdf

new url;


OR-12: Chronic wasting disease transmission and pathogenesis in cervid and non-cervid Species 

Edward A. Hoover, Candace K. Mathiason, Nicholas J. Haley, Timothy D. Kurt, Davis M. Seelig, Nathaniel D. Denkers, Amy V. Nalls, Mark D. Zabel, and Glenn C. Telling Prion Research Program, Department of Microbiology, Immunology, and Pathology; Colorado State University; Fort Collins, CO USA 

Since its recognition as a TSE in the late 1970s, chronic wasting disease (CWD) of cervids has been distinguished by its facile spread and is now recognized in 18 states, 2 Canadian provinces, and South Korea. The efficient horizontal spread of CWD reflects a prion/host relationship that facilitates efficient mucosal uptake, peripheral lymphoid amplification, and dissemination by exploiting excretory tissues and their products, helping to establish indirect/environmental and well as direct (e.g., salivary) transmission. Recent studies from our group also support the likelihood of early life mother to offspring and aerosol CWD prion transmission. Studies of cervid CWD exposure by natural routes indicate that incubation period for detection of overt infection, while still uncertain, may be much longer than originally thought. Several non-cervid species can be infected by CWD experimentally (e.g., ferrets, voles, cats) with consequent species-specific disease phenotypes. The species-adapted prions so generated can be transmitted by mucosal, i.e., more natural, routes. Whether non-cervid species sympatric with deer/elk can be infected in nature, however, remains unknown. In vitro CWD prion amplification studies, in particular sPMCA, can foreshadow in vivo susceptibility and suggest the importance of the PrPC rigid loop region in species barrier permissiveness. Trans-species CWD amplification appears to broaden the host range/strain characteristics of the resultant prions. The origins of CWD remain unknown, however, the existence of multiple CWD prion strains/ quasi-species, the mechanisms of prion shedding/dissemination, and the relationship between sheep scrapie and CWD merit further investigation. 

http://www.landesbioscience.com/journals/prion/01-Prion6-2-OralPresentations.pdf 


Friday, August 8, 2008

PS 76-59: White-tailed deer carcass decomposition and risk of chronic wasting disease exposure to scavenger communities in Wisconsin

Chris S. Jennelle, Michael D. Samuel, Cherrie A. Nolden, and Elizabeth A. Berkley. University of Wisconsin

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Chronic wasting disease (CWD) is an infectious transmissible spongiform encephalopathy (TSE) afflicting members of the family Cervidae, and causes neurodegeneration and ultimately death. While there have been no reports of natural cross-species transmission of CWD outside this group, we addressed the role of white-tailed deer (Odocoileus virginianus) carcasses as environmental sources of CWD in Wisconsin. Our objectives were to estimate rates of deer carcass and gut pile decomposition in the environment, characterize vertebrate scavenger communities, and quantify the relative activity of scavengers to determine CWD exposure risk. We placed 40 disease-free deer carcasses and nine gut piles in the CWD-affected area of Wisconsin from September to April in 2003 through 2005. We used photos from remotely operated cameras to characterize scavenger communities and relative activity. We used Kaplan-Meier survival analysis and a generalized linear mixed model to quantify the driving factors and rate of carcass removal (decomposition) from the environment.

Results/Conclusions

We recorded 14 species of scavenging mammals (six visiting species), and eight species of scavenging birds (14 visiting species). Prominent scavengers included American crows (Corvus brachyrhynchos), raccoons (Procyon lotor), and Virginia opossums (Didelphis virginiana). We found no evidence that deer directly consumed conspecific remains, although they visited them frequently. Domestic dogs (Canis familiaris), cats (Felis catus), and cows (Bos spp.) either scavenged or visited carcass sites, which could increase exposure risk of CWD to humans and human food supplies. Deer carcasses persisted for a median of 18 to 101 days, while gut piles lasted for a median of three days. Habitat did not influence carcass decomposition, but mammalian and avian scavenger activity and higher temperatures (proxy for microbial and arthropod activity) were associated with greater rates of carcass removal. Infected deer carcasses serve as environmental sources of CWD prions to a wide variety of mammalian and avian scavengers. Such sources of infectious material likely influence the maintenance and spread of CWD (in particular), and should be considered in the dynamics of other disease systems as well. Prudence would dictate the use of preemptive management strategies, and we highlight strategies for carcass disposal to mitigate the influence of carcasses as environmental sources of infectious diseases.

See more of The 93rd ESA Annual Meeting (August 3 -- August 8, 2008)



SUNDAY, SEPTEMBER 01, 2013 

hunting over gut piles and CWD TSE prion disease 

hunting over gut piles and CWD TSE prion disease, a reminder...just saying


SUNDAY, JULY 07, 2013 

Could avian scavengers translocate infectious prions to disease-free areas initiating new foci of chronic wasting disease?


Wednesday, October 17, 2012 

Prion Remains Infectious after Passage through Digestive System of American Crows (Corvus brachyrhynchos) 


Sunday, November 01, 2009 

AS THE CROW FLIES, SO DOES CWD American crows (Corvus brachyrhynchos) and potential spreading of CWD through feces of digested infectious carcases 


Monday, July 13, 2009 

Deer Carcass Decomposition and Potential Scavenger Exposure to Chronic Wasting Disease 


Monday, February 14, 2011 

THE ROLE OF PREDATION IN DISEASE CONTROL: A COMPARISON OF SELECTIVE AND NONSELECTIVE REMOVAL ON PRION DISEASE DYNAMICS IN DEER 

NO, NO, NOT NO, BUT HELL NO ! 

Journal of Wildlife Diseases, 47(1), 2011, pp. 78-93 © Wildlife Disease Association 2011 


These results provide strong evidence for the emergence of a novel strain of CWD after passage in meadow voles and raccoons. Therefore, interspecies transmission of CWD prions between cervids and noncervid species that share the same habitat might represent a confounding factor in CWD-management programs. In addition, passage of CWD prions through off-target species might represent a source of novel CWD strains with unknown biologic characteristics, including zoonotic potential. Characterization of the biologic behavior of CWD isolates after cross-species transmission will help us develop more effective management strategies for CWD-affected populations.


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

Title: Passage of the CWD agent through meadow voles results in increased attack rates and decreased incubation periods in raccoons

Author item MOORE, SARA JO - Orise Fellow item CARLSON, CHRISTINA - Us Geological Survey (USGS) item SCHNEIDER, JAY - Us Geological Survey (USGS) item JOHNSON, CHRISTOPHER - Us Geological Survey (USGS) item Greenlee, Justin Submitted to: Emerging Infectious Diseases Publication Type: Peer Reviewed Journal Publication Acceptance Date: 12/13/2021 Publication Date: N/A Citation: N/A Interpretive 

Summary: Transmissible spongiform encephalopathies (TSEs) are a group of fatal diseases caused by the accumulation of misfolded prion protein in the brain. Several livestock species including cattle, sheep, deer, and elk are afflicted by prion diseases. In sheep the disease is called scrapie. In deer and elk, the disease is called chronic wasting disease (CWD). Due to the human consumption of cervid meat products and intermingling of various livestock species with wild cervid populations, there is significant interest in characterizing the possible host range of CWD. This study reports the successful transmission of the CWD agent to raccoons, a ubiquitous omnivore present throughout North America. In addition, passage of the CWD agent from deer through meadow voles, a scavenger present in much of the range where CWD occurs, results in changes in the biological behavior of the CWD agent when that material is used to inoculate raccoons. This research is of interest to regulatory officials or anyone interested in controlling CWD in wildlife or captive cervid herds.

Technical Abstract: Chronic wasting disease (CWD) is a naturally-occurring neurodegenerative disease of cervids. Raccoons (Procyon lotor) and meadow voles (Microtus pennsylvanicus) have previously been shown to be susceptible to CWD and their scavenging habits could expose them to environmental CWD infectivity. To investigate the potential for transmission of the agent of CWD from white-tailed deer to voles and subsequently to raccoons, we intracranially inoculated raccoons with brain homogenate from a CWD-affected white-tailed deer (CWDWtd), or derivatives of this isolate after it had been passaged through voles one or five times. We found that passage of the CWDWtd isolate through voles led to a change in the biological behavior of the CWD agent, including increased attack rates and decreased incubation periods in raccoons. A better understanding of the dynamics of cross-species transmission of CWD prions will help us to better manage and control the spread of CWD in free-ranging and farmed cervid populations.


2. Passage through a new species alters chronic wasting disease transmission. Due to the human consumption of cervid meat products and intermingling of various livestock species with wild cervid populations, there is significant interest in characterizing the possible host range of CWD. ARS scientists in Ames, Iowa, demonstrated that passage of chronic wasting disease (CWD) prion (the CWD causative agent) through meadow voles results in increased attack rates and decreased incubation periods when vole passaged CWD prions were then experimentally inoculated into raccoons, which is a ubiquitous omnivore present throughout North America. Passage of the CWD agent from deer through meadow voles, a scavenger present in much of the range where CWD occurs, results in changes in the biological behavior of the CWD agent when that material is used to inoculate raccoons. This research is of interest to regulatory officials, or anyone interested in controlling CWD in wildlife or captive cervid herds.


Research Project: Elucidating the Pathobiology and Transmission of Transmissible Spongiform Encephalopathies Location: Virus and Prion Research

Title: The chronic wasting disease agent from white-tailed deer is highly infectious to humanized mice after passage through raccoons

Author item Cassmann, Eric item QI, XU - Case Western Reserve University (CWRU) item KONG, QINGZHONG - Case Western Reserve University (CWRU) item Greenlee, Justin

Submitted to: Meeting Abstract Publication Type: Abstract Only Publication Acceptance Date: 3/15/2023 Publication Date: 5/30/2023 Citation: Cassmann, E.D., Qi, X., Kong, Q., Greenlee, J.J. 2023. The chronic wasting disease agent from white-tailed deer is highly infectious to humanized mice after passage through raccoons (abstract). Meeting Abstract. 4th International Chronic Wasting Disease Symposium, May 30-June 3, 2023, Denver, Colorado. Interpretive Summary:

Technical Abstract: The aim of this study was to evaluate the zoonotic potential of the raccoon passaged chronic wasting disease (CWD) agent in humanized transgenic mice in comparison with the North American CWD agent from the original white-tailed deer (WTD) host. Pooled brain (GG96) from CWD positive deer was used to intracranially inoculate two WTD and one raccoon. Brain homogenates (10% w/v) from the raccoon and the WTD were used to intracranially inoculate transgenic mice (Tg40h) expressing the methionine 109 human prion protein. Brains and spleens were collected from mice at experimental endpoints of clinical disease or approximately 700 days post-inoculation. Tissues were divided and homogenized or fixed in 10% buffered neutral formalin. Immunohistochemistry, enzyme immunoassay, and western blot were used to detect misfolded prion protein (PrPSc) in tissue. Tg40h mice inoculated with the raccoon passaged CWD agent from WTD exhibited a 100% (12/12) attack rate with an average incubation period of 605 days. PrPSc was detected in brain tissue by enzyme immunoassay with an average optical density of 3.6/4.0 for positive brains. PrPSc also was detected in brain tissue by western blot and immunohistochemistry. No PrPSc was detected in the spleens of mice inoculated with the raccoon passaged CWD agent. Humanized mice inoculated with the CWD agent from WTD did not have detectable PrPSc using conventional immunoassay techniques. These results demonstrated that the host range of the CWD agent from WTD was expanded in our experimental model after one passage through raccoons.


Could avian scavengers translocate infectious prions to disease-free areas initiating new foci of chronic wasting disease?

Justin W Fischer, Gregory E Phillips, Tracy A Nichols &Kurt C VerCauteren

Pages 263-266 | Received 03 Jun 2013, Accepted 03 Jul 2013, Published online: 03 Jul 2013


Abstract

Mechanisms for the spread of transmissible spongiform encephalopathy diseases, including chronic wasting disease (CWD) in North American cervids, are incompletely understood, but primary routes include horizontal and environmental transmission. Birds have been identified as potential vectors for a number of diseases, where they ingest or are exposed to infected material and later shed the disease agent in new areas after flying substantial distances. We recently identified American crows (Corvus brachyrhynchos) as having the potential to translocate infectious prions in their feces. Our results suggest that this common, migratory North American scavenger is capable of translocating infectious prions to disease-free areas, potentially seeding CWD infection where no other initial source of pathogen establishment is forthcoming. Here we speculate on the role avian scavengers, like American crows, might play in the spatial dissemination of CWD. We also consider the role mammalian scavengers may play in dispersing prions.

snip...

In conclusion, our study showed that the digestive system of crows did not eliminate PrPRes infectivity prior to excretion of feces,Citation21 which suggests that avian scavengers may play a role in the transmission and translocation of prion diseases. Relatedly, crows often forage and defecate on feed at farmed cervid facilities, providing an opportunity for farmed cervids to ingest crow feces and crows to ingest feed with elk saliva, and other potentially PrPRes-infected material. Further experiments involving other avian, as well as mammalian, scavengers are needed to evaluate PrPRes infectivity after passage of natural transmissible spongiform encephalopathies through their digestive systems. We are currently conducting a study to evaluate CWD passage through the digestive system of coyotes. It would be prudent to evaluate other mammalian scavengers for their ability to act as intermediate CWD hosts between cervids and humans.

Acknowledgments

Keywords: : American crows Corvus brachyrhynchos CWD disease transmission transmissible spongiform encephalopathy TSE


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

snip...

R. BRADLEY


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. 


mountain lion (Puma concolor)

The size of a lion’s home range is determined by a variety of factors: prey abundance and availability, topography and other habitat features, and presence of other lions. Male home ranges average 2-1/2 times larger than those of females. The male’s range usually encompasses the range of several females. Research has shown some overlap in home ranges of adult males, but normally males do not share ranges. The home range of an adult male may vary from 80 to 200 square miles, while female ranges are normally 20 to 100 square miles. Female ranges tend to have some degree of overlap with those of other females, although they remain solitary.

snip...

Lions are capable of taking large animals including livestock, but in general, reports of mature cattle and horse kills should be viewed with skepticism. Mountain lions rarely kill animals weighing over 500 pounds.

When investigating a reported lion kill, remember that lions leave an abundance of sign. Look for tracks. Drag marks are a good indication of a lion kill. The drag mark is usually wide and clear if the prey is large, and it is fairly straight from the kill site to the cache area (Figure 9). Lions cache their kills in areas of heavy cover. They often cover their kill with grass, leaves, dirt or other debris, but they do not bury their kill (Figure 10). They often remove the internal organs and cover them up, close to the kill site. Lions frequently uncover their kill and feed, then drag the carcass to another area and cover it again.


Fri, Mar 24, 2023 at 3:46 PM

Mountain lions, Wolves, Coyotes, could help stop the spread of CWD TSE Prion in deer, WHERE STUPID MEETS THE ROAD!

i have written about this over the past 23 years or so (i.e. BMJ 2000 comment), every time i hear someone say that big cats, or wolves, or coyote, will help eradicate chronic wasting disease cwd TSE Prion disease, i just cringe. 

They are going to do this on their own, natural instinct, but to mandate such an act, i.e. using wolves, big cats, coyote, as a TOOL, financed in any way, mandate, make a law, i think this would be a bad idea. 

i will post a few of the reasons why this is not a good idea, on the contrary, i believe it would amply the spreading of cwd tse prion by unnatural means, i.e. stupid ideas and man...terry

FRIDAY, MARCH 24, 2023 

Mountain lions, Wolves, Coyotes, could help stop the spread of CWD TSE Prion in deer, WHERE STUPID MEETS THE ROAD! 



Title: Disease phenotype of classical sheep scrapie is changed upon experimental passage through white-tailed deer 

Author item Kokemuller, Robyn item MOORE, S.JO - Oak Ridge Institute For Science And Education (ORISE) item Bian, Jifeng item WEST GREENLEE, HEATHER - Iowa State University item Greenlee, Justin

Submitted to: PLoS Pathogens Publication Type: Peer Reviewed Journal Publication Acceptance Date: 11/9/2023 Publication Date: 12/4/2023 Citation: Kokemuller, R., Moore, S., Bian, J., West Greenlee, H.M., Greenlee, J.J. 2023. Disease phenotype of classical sheep scrapie is changed upon experimental passage through white-tailed deer. PLoS Pathogens. https://doi.org/10.1371/journal.ppat.1011815. DOI: https://doi.org/10.1371/journal.ppat.1011815 Interpretive Summary: Transmissible spongiform encephalopathies (TSEs) are a group of fatal diseases caused by the accumulation of misfolded prion protein in the brain. Ruminant species such as sheep, deer, and elk can get prion diseases. In sheep the disease is called scrapie. In deer and elk, the disease is called chronic wasting disease (CWD). The source of CWD is unknown, but one possibility is that scrapie jumped from sheep to deer. When we experimentally exposed white-tailed deer to the sheep scrapie agent, all deer developed scrapie. The purpose of the current experiment was to determine if sheep can get scrapie derived from white-tailed deer. Some sheep developed scrapie after oronasal exposure to the scrapie agent from white-tailed deer. Passage through white-tailed deer results in a scrapie isolate with different strain properties than the original inoculum. The detection of new strain properties was an unexpected result that will be the subject of further studies. These results indicate that sheep could be susceptible to the scrapie agent after passage through deer if exposed to the agent in natural or agricultural settings, which could be a confounding factor to the scrapie eradication program. National and state regulatory and wildlife officials should consider this information when developing plans to reduce or eliminate TSEs.

Technical Abstract: Transmissible spongiform encephalopathy (TSE) agents have strain variations that influence disease phenotype and may affect the potential for interspecies transmission. Since deer and sheep may use the same grazing land, it is important to understand the potential transmission of TSEs between these species. The US scrapie isolate (No.13-7) had a 100% attack rate in white-tailed deer after oronasal challenge. The purpose of this study was to determine if sheep are susceptible to oronasal challenge with the scrapie agent from white-tailed deer. Suffolk lambs of various prion protein genotypes were challenged by the oronasal route with a 10% brain homogenate from scrapie-affected white-tailed deer. Sheep were euthanized and necropsied upon development of clinical signs or at the end of the experiment (72 months post-inoculation). Tissues were tested for PrPSc by enzyme immunoassay, western blot, and immunohistochemistry. The first sheep (2/2) to develop clinical signs at approximately 29 months post-inoculation (MPI) had the VRQ/VRQ genotype. One of the two sheep with the ARQ/ARQ genotype also developed clinical signs at 48 MPI. This is in contrast to the original No.13-7 inoculum that has a faster incubation period in sheep with the ARQ/ARQ genotype compared to sheep of the VRQ/VRQ genotype. The shorter incubation period in VRQ/VRQ sheep than ARQ/ARQ sheep after passage through deer indicates a phenotype change. This is important because scrapie infected deer could transmit disease to sheep resulting in new scrapie strain properties. This work raises the concern that scrapie infected deer could serve as a confounding factor to scrapie eradication programs as the scrapie agent from deer is transmissible to sheep by the oronasal route.


***> 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 


Rapid recontamination of a farm building occurs after attempted prion removal First published: 19 January 2019 https://doi.org/10.1136/vr.105054

The data illustrates the difficulty in decontaminating farm buildings from scrapie, and demonstrates the likely contribution of farm dust to the recontamination of these environments to levels that are capable of causing disease. snip...

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 scrapie positive 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. 


***>This is very likely to have parallels with control efforts for CWD in cervids. 


Front. Vet. Sci., 14 September 2015 | https://doi.org/10.3389/fvets.2015.00032

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

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


172. Establishment of PrPCWD extraction and detection methods in the farm soil

Conclusions: Our studies showed that PrPCWD persist in 0.001% CWD contaminated soil for at least 4 year and natural CWD-affected farm soil. When cervid reintroduced into CWD outbreak farm, the strict decontamination procedures of the infectious agent should be performed in the environment of CWD-affected cervid habitat.


Plants as vectors for environmental prion transmission

Published: November 09, 2023DOI:https://doi.org/10.1016/j.isci.2023.108428

Advertisement Highlights

• Abnormal prion protein can enter the roots of plants

• Plants can translocate detectable levels of prions to aerial tissues

•Animals exposed to prion-contaminated plant tissues can acquire disease

•Contaminated plants may represent a route of prion exposure

Snip…

Nonetheless, our finding of accumulation of two prion strains by a variety of plants grown hydroponically, in agar, or on soil supports the potential for plants to acquire CWD, scrapie, or other prions from the environment and transmit prion disease to susceptible hosts, making plants a plausible vector for prion diseases in wildlife, livestock, and humans. The potential for plants to serve as vectors for prion disease has implications for the disposal of infected carcasses, grazing practices, and the use and transport of potentially contaminated crop materials.



Carrot plants as potential vectors for CWD transmission.

The PMCA analysis demonstrated CWD seeding activity in soils contaminated with CWD prions and in carrot plants (leaves and roots) grown on them. Bioassays showed that both plants and roots contained CWD prions sufficiently to induce disease. As expected, animals treated with prion-infected soils developed prion disease at shorter incubation periods (and complete attack rates) compared to plant components. We show that edible plant components can absorb prions from CWD-contaminated soils and transport them to their aerial parts. Our results indicate that edible plants could participate as vectors of CWD transmission.


“In addition, hay and straw from the United States and Canada must be accompanied by a certificate from a public veterinarian that the product has been harvested in states or provinces where Chronic Wasting Disease has not been detected on deer.”

Regulation No. 1599 of 2018 on additional requirements for the import of hay and straw for used for animal feed.

Country Norway

Type of law Regulation

Source

FAO , FAOLEX

In addition, hay and straw from the United States and Canada must be accompanied by a certificate from a public veterinarian that the product has been harvested in states or provinces where Chronic Wasting Disease has not been detected on deer.


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

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

you cannot cook the TSE prion disease out of meat. 

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

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

the TSE prion agent also survives Simulated Wastewater Treatment Processes. 

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

you can bury it and it will not go away. 

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

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

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


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


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


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


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


THURSDAY, FEBRUARY 28, 2019 

BSE infectivity survives burial for five years with only limited spread


CWD TSE PRION CERVID ENVIRONMENTAL RISK FACTORS 2023

So, this is what we leave our children and grandchildren?..

"Additionally, we have determined that prion seeding activity is retained for at least fifteen years at a contaminated site following attempted remediation."

Detection of prions in soils contaminated by multiple routes

Results: We are able to detect prion seeding activity at multiple types of environmental hotspots, including carcass sites, contaminated captive facilities, and scrapes (i.e. urine and saliva). Differences in relative prion concentration vary depending on the nature and source of the contamination. Additionally, we have determined that prion seeding activity is retained for at least fifteen years at a contaminated site following attempted remediation. Conclusions: Detection of prions in the environment is of the utmost importance for controlling chronic wasting disease spread. Here, we have demonstrated a viable method for detection of prions in complex environmental matrices. However, it is quite likely that this method underestimates the total infectious prion load in a contaminated sample, due to incomplete recovery of infectious prions. Further refinements are necessary for accurate quantification of prions in such samples, and to account for the intrinsic heterogeneities found in the broader environment.

=====end

Prion 2023 Abstracts


“Transmissible spongiform encephalopathy (TSE) agents have strain variations that influence disease phenotype and may affect the potential for interspecies transmission. Since deer and sheep may use the same grazing land, it is important to understand the potential transmission of TSEs between these species. The US scrapie isolate (No.13-7) had a 100% attack rate in white-tailed deer after oronasal challenge.”

https://www.ars.usda.gov/research/publications/publication/?seqNo115=405929

''They often remove the internal organs and cover them up, close to the kill site. Lions frequently uncover their kill and feed, then drag the carcass to another area and cover it again.''

BAD IDEA!!!

Terry S. Singeltary Sr.

posted by Terry S. Singeltary Sr. at 12:58 PM

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