Texas TAHC TPWD Confirm 132 More Cases of CWD TSE PrP 795 Positive To Date
THURSDAY, MARCH 07, 2024
Texas TPWD CWD Cases Jump to 663 Confirmed To Date
https://chronic-wasting-disease.blogspot.com/2024/03/texas-tpwd-cwd-cases-jump-to-663.html
“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.
9 Carrot plants as potential vectors for CWD transmission.
Paulina Soto1,2, Francisca Bravo-Risi1,2, Claudio Soto1, Rodrigo Morales1,2
1Department of Neurology, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, USA. 2Universidad Bernardo O’Higgins, Santiago, Chile
***> 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
=====
https://intcwdsympo.files.wordpress.com/2023/06/final-agenda-with-abstracts.pdf?force_download=true
Carrot plants as potential vectors for CWD transmission
Paulina Sotoa,b, Francisca Bravo-Risia,b, Claudio Sotoa, and Rodrigo Moralesa,b
aDepartment of Neurology, McGovern Medical School, University of Texas Health Science Center at Houston, Texas, USA; bUniversidad Bernardo O’Higgins, Santiago, Chile
Prion diseases are infectious neurodegenerative disorders afflicting humans and other mammals. These diseases are generated by the misfolding of the cellular prion protein into a disease-causing isoform. Chronic wasting disease (CWD) is a prevalent prion disease affecting cervids (captive and free-range). CWD is thought to be transmitted through direct animal contact or by indirect exposure to contaminated environments. Many studies have shown that infectious prions can enter the environment through saliva, feces, or urine from infected animals and decaying carcasses. However, we do not fully understand the specific contribution of each component to disease transmission events. Plants are logical environmental components to be evaluated since they grow in environments contaminated with CWD prions and are relevant for animal and human nutrition.
Aims: The main objective of this study is to study whether prions are transported to the roots and leaves of carrots, an edible plant commonly used in the human diet and as deer bait.
Methods: We have grown carrot plants in CWD-infected soils. After 90 days, we harvested the carrots and separated them from the leaves. The experiment was controlled by growing plants in soil samples treated with brain extracts from healthy animals. These materials were interrogated for their prion seeding activity using the Protein Misfolding Cyclic Amplification (PMCA) technique. Infectivity was evaluated in mouse bioassays (intracerebral injections in Tg1536 mice). The animals were sacrificed when they showed established signs of prion disease. Animals not displaying clinical signs were sacrificed at 600 days post-inoculation.
Results: The PMCA analysis demonstrated CWD seeding activity in soils contaminated with CWD prions, as well as in carrot plants (leaves and roots) grown on them. Bioassays demonstrated that both leaves and roots contained CWD prions in sufficient quantities to induce disease (92% attack rate). As expected, animals treated with prion-infected soils developed prion disease at shorter incubation periods (and complete attack rates) compared to plant components. Animals treated with soil and plant components exposed with CWD-free brain extracts did not display prion-associated clinical signs or evidence of sub-clinical prion infection.
Conclusions: We show that edible plant components can absorb prions from CWD contaminated soils and transport them to their aerial parts. Our results indicate that plants could participate as vectors of CWD transmission. Importantly, plants designated for human consumption represent a risk of introducing CWD prions into the human food chain.
Funded by: NIH
Grant number: R01AI132695
P.157: Uptake of prions into plants
Christopher Johnson1, Christina Carlson1, Matthew Keating1,2, Nicole Gibbs1, Haeyoon Chang1, Jamie Wiepz1, and Joel Pedersen1 1USGS National Wildlife Health Center; Madison, WI USA; 2University of Wisconsin - Madison; Madison, WI USA
Soil may preserve chronic wasting disease (CWD) and scrapie infectivity in the environment, making consumption or inhalation of soil particles a plausible mechanism whereby na€ıve animals can be exposed to prions. Plants are known to absorb a variety of substances from soil, including whole proteins, yet the potential for plants to take up abnormal prion protein (PrPTSE) and preserve prion infectivity is not known. In this study, we assessed PrPTSE uptake into roots using laser scanning confocal microscopy with fluorescently tagged PrPTSE and we used serial protein misfolding cyclic amplification (sPMCA) and detect and quantify PrPTSE levels in plant aerial tissues. Fluorescence was identified in the root hairs of the model plant Arabidopsis thaliana, as well as the crop plants alfalfa (Medicago sativa), barley (Hordeum vulgare) and tomato (Solanum lycopersicum) upon exposure to tagged PrPTSE but not a tagged control preparation. Using sPMCA, we found evidence of PrPTSE in aerial tissues of A. thaliana, alfalfa and maize (Zea mays) grown in hydroponic cultures in which only roots were exposed to PrPTSE. Levels of PrPTSE in plant aerial tissues ranged from approximately 4 £ 10 ¡10 to 1 £ 10 ¡9 g PrPTSE g ¡1 plant dry weight or 2 £ 105 to 7 £ 106 intracerebral ID50 units g ¡1 plant dry weight. Both stems and leaves of A. thaliana grown in culture media containing prions are infectious when intracerebrally-injected into mice.
***Our results suggest that prions can be taken up by plants and that contaminated plants may represent a previously unrecognized risk of human, domestic species and wildlife exposure to prions.
===========
***Our results suggest that prions can be taken up by plants and that contaminated plants may represent a previously unrecognized risk of human, domestic species and wildlife exposure to prions.
DISCUSSION
This study shows that plants can efficiently bind prions contained in brain extracts from diverse prion infected animals, including CWD-affected cervids. PrPSc attached to leaves and roots from wheat grass plants remains capable of seeding prion replication in vitro. Surprisingly, the small quantity of PrPSc naturally excreted in urine and feces from sick hamster or cervids was enough to efficiently contaminate plant tissue. Indeed, our results suggest that the majority of excreted PrPSc is efficiently captured by plants’ leaves and roots. Moreover, leaves can be contaminated by spraying them with a prion-containing extract, and PrPSc remains detectable in living plants for as long as the study was performed (several weeks). Remarkably, prion contaminated plants transmit prion disease to animals upon ingestion, producing a 100% attack rate and incubation periods not substantially longer than direct oral administration of sick brain homogenates. Finally, an unexpected but exciting result was that plants were able to uptake prions from contaminated soil and transport them to aerial parts of the plant tissue. Although it may seem farfetched that plants can uptake proteins from the soil and transport it to the parts above the ground, there are already published reports of this phenomenon (McLaren et al., 1960; Jensen and McLaren, 1960; Paungfoo-Lonhienne et al., 2008). The high resistance of prions to degradation and their ability to efficiently cross biological barriers may play a role in this process. The mechanism by which plants bind, retain, uptake, and transport prions is unknown. We are currently studying the way in which prions interact with plants using purified, radioactively labeled PrPSc to determine specificity of the interaction, association constant, reversibility, saturation, movement, etc.
Epidemiological studies have shown numerous instances of scrapie or CWD recurrence upon reintroduction of animals on pastures previously exposed to prion-infected animals. Indeed, reappearance of scrapie has been documented following fallow periods of up to 16 years (Georgsson et al., 2006), and pastures were shown to retain infectious CWD prions for at least 2 years after exposure (Miller et al., 2004). It is likely that the environmentally mediated transmission of prion diseases depends upon the interaction of prions with diverse elements, including soil, water, environmental surfaces, various invertebrate animals, and plants. However, since plants are such an important component of the environment and also a major source of food for many animal species, including humans, our results may have far-reaching implications for animal and human health. Currently, the perception of the risk for animal-to-human prion transmission has been mostly limited to consumption or exposure to contaminated meat; our results indicate that plants might also be an important vector of transmission that needs to be considered in risk assessment.
snip...see full text here ;
Grass Plants Bind, Retain, Uptake, and Transport Infectious Prions
PRION UPDATE VIA VEGETABLE PLANTS FROM THE SOIL
56. Members considered that there is no evidence that crops grown on the land which received composted excreta from BSE-challenged animals pose a TSE risk to humans or animals. One member suggested that, as some of these animals are orally challenged with high doses of BSE-infected materials, and the distribution of infectivity in the digestive system is not completely understood, it might be premature to conclude that there is no infective agent in the manure.
Furthermore, an unpublished study had indicated low level absorption of PrP from soil by tomato plants although it should be noted that this study had not been repeated. Details of this work would be sent to the SEAC Secretary. Dr Matthews explained that most of the manure from animals challenged with high doses of BSE had already been composted and used for coppicing. Members agreed that the risks from disposal of residual manure from experimental animals would be much less than historic risks of on farm contamination from naturally infected animals at the height of the BSE epidemic. ...SNIP...END
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.
This content is exclusively provided by
FAO, FAOLEX
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
Abstract
This Regulation seeks to prevent the spread of infectious animal diseases that can be caused by the importation of hay and straw used in animal feed from countries outside the European Economic Area. Hay and straw imported into Norway as animal feed must: (a) be accompanied by a confirmation from the manufacturer that the product has been stored for at least two months in the country of dispatch and harvested from farms where no animal manure has been fertilized during the past two years; and b) be accompanied by a certificate from a public veterinarian in the country of dispatch that the product has been harvested from farms where no restrictions have been set due to infectious animal disease. 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.
Attached files
Web site
Date of text
22 Oct 2018
Repealed
No
Source language
English
Legislation Amendment
No
Original title
Forskrift om tilleggskrav ved import av høy og halm til dyrefôr.
Amends
Regulation prohibiting the importation of animals and infectious objects. on 22 Oct 2018
"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
Stuart Siegfried Lichtenberg1,2 , Heather Inzalaco3 , Sam Thomas4 , Dan Storm5 , Dan Walsh6
1Department of Veterinary and Biomedical Sciences, University of Minnesota, St. Paul, Minnesota, U.S.A.
2Minnesota Center for Prion Research and Outreach, University of Minnesota, St. Paul, Minnesota, U.S.A.
3 Wisconsin Cooperative Wildlife Research Unit, Department of Forest and Wildlife Ecology, University of Wisconsin-Madison, Madison, Wisconsin, U.S.A
4Department of Soil Science, University of Wisconsin-Madison, Madison, Wisconsin, U.S.A.
5Wisconsin Department of Natural Resources, Eau Claire, Wisconsin, U.S.A.
6U.S. Geological Survey, Montana Cooperative Wildlife Research Unit, University of Montana, Missoula, Montana, U.S.A.
Aims: Free-ranging animals afflicted with transmissible spongiform encephalopathies frequently shed infectious prions into the broader environment. The quintessential example is chronic wasting disease, the TSE of cervids. Over the course of the disease, an infected animal will shed infectious prions in blood, urine, saliva, and feces. Upon death, the total prion load interred in the animal’s tissues will be deposited wherever the animal falls. This contamination creates substantial risk to naïve animals, and likely contributes to disease spread. Identification and quantification of prions at contamination hotspots is essential for any attempt at mitigation of environmental transmission.
Materials and Methods: Surfactant extraction of soils followed by precipitation yields a sample that is amenable to analysis by real-time quaking induced conversion. However, differences in extraction yield are apparent depending on the properties of the matrix from which the prions are being extracted, principally soil clay content.
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.
Funded by: Wisconsin Department of Natural Resources
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Prion 2023 Abstracts
***> 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.
Chronic wasting disease detection in environmental and biological samples from a taxidermy site
Paulina Sotoa,b, J. Hunter Reedc, Mitch Lockwoodc, and Rodrigo Moralesa,b
aDepartment of Neurology, McGovern Medical School, University of Texas Health Science Center at Houston, Texas, USA; bUniversidad Bernardo O’Higgins, Santiago, Chile; cTexas Parks and Wildlife Department, Texas, USA
Chronic wasting disease (CWD) is a transmissible spongiform encephalopathy affecting captive and free-ranging cervids (e.g., mule deer, white-tailed deer, elk, reindeer, and moose). Nowadays, CWD is widely distributed in North America. It is suggested that CWD spreads due to direct animal contact or through exposure to contaminated environments previously inhabited by infected animals. CWD may also be spread through the movement of infected animals and carcasses. Taxidermy practices involve processing deer tissues (or whole animal carcasses). In many cases, the CWD status of processed animals is unknown. This can generate risks of disease spread and transmission. Taxidermy practices include different steps involving physical, chemical, and biological procedures. Without proper tissue handling or disposal practices, taxidermist facilities may become a focus of prion infectivity.
Aims: In this study, we evaluated the presence of infectious prions in a taxidermy facility believed to be exposed to CWD. Detection was performed using the Protein Misfolding Cyclic Amplification (PMCA) technique in biological and inert environmental samples.
Methods: We collected biological and environmental samples (plants, soils, insects, excreta, and others) from a taxidermy facility, and we tested these samples using the PMCA technique. In addition, we swabbed different surfaces possibly exposed to CWD-infected animals. For the PMCA reaction, we directly used a swab piece or 10 µL of 20% w/v homogenized samples.
Results: The PMCA analysis demonstrated CWD seeding activity in some of the components of this facility, including insects involved in head processing, soils, and a trash dumpster.
Conclusions: Different areas of this property were used for various taxidermy procedures. We were able to detect the presence of prions in i) soils that were in contact with the heads of dead animals, ii) insects involved in the cleaning of skulls, and iii) an empty dumpster where animal carcasses were previously placed. This is the first report demonstrating that swabbing is a helpful method to screen for prion infectivity on surfaces potentially contaminated with CWD. These findings are relevant as this swabbing and amplification strategy may be used to evaluate the disease status of other free-ranging and captive settings where there is a concern for CWD transmissions, such as at feeders and water troughs with CWD-exposed properties. This approach could have substantial implications for free-ranging cervid surveillance as well as in epidemiological investigations of CWD.
Funded by: USDA
Grant number: AP20VSSPRS00C143
PRION 2022 ABSTRACTS, AND A BIG THANK YOU TO On behalf of the Prion2020/2022 Congress Organizing Committee and the NeuroPrion Association, we heartily invite you to join us for the International Conference Prion2020/2022 from 13.-16. September 2022 in Göttingen.
Prion 2022 Conference abstracts: pushing the boundaries
Large-scale PMCA screening of retropharyngeal lymph nodes and in white-tailed deer and comparisons with ELISA and IHC: the Texas CWD study
Rebeca Benaventea, Paulina Sotoa, Mitch Lockwoodb, and Rodrigo Moralesa aDepartment of Neurology, McGovern Medical School, University of Texas Health Science Center at Houston, Texas, USA; bTexas Park and Wildlife Department, Texas, USA
Chronic wasting disease (CWD) is a transmissible spongiform encephalopathy that affects various species of cervids, and both free-ranging and captive animals. Until now, CWD has been detected in 3 continents: North America, Europe, and Asia. CWD prevalence in some states may reach 30% of total animals. In Texas, the first case of CWD was reported in a free-range mule deer in Hudspeth and now it has been detected in additional 14 counties. Currently, the gold standard techniques used for CWD screening and detection are ELISA and immunohistochemistry (IHC) of obex and retropharyngeal lymph nodes (RPLN). Unfortunately, these methods are known for having a low diagnostic sensitivity. Hence, many CWD-infected animals at pre-symptomatic stages may be misdiagnosed. Two promising in vitro prion amplification techniques, including the real-time quaking-induced conversion (RT-QuIC) and the protein misfolding cyclic amplification (PMCA) have been used to diagnose CWD and other prion diseases in several tissues and bodily fluids. Considering the low cost and speed of RT-QuIC, two recent studies have communicated the potential of this technique to diagnose CWD prions in RPLN samples. Unfortunately, the data presented in these articles suggest that identification of CWD positive samples is comparable to the currently used ELISA and IHC protocols. Similar studies using the PMCA technique have not been reported.
Aims: Compare the CWD diagnostic potential of PMCA with ELISA and IHC in RPLN samples from captive and free-range white-tailed deer. Material and Methods: In this study we analyzed 1,003 RPLN from both free-ranging and captive white-tailed deer collected in Texas. Samples were interrogated with the PMCA technique for their content of CWD prions. PMCA data was compared with the results obtained through currently approved techniques.
Results: Our results show a 15-fold increase in CWD detection in free-range deer compared with ELISA. Our results unveil the presence of prion infected animals in Texas counties with no previous history of CWD. In the case of captive deer, we detected a 16% more CWD positive animals when compared with IHC. Interestingly, some of these positive samples displayed differences in their electroforetic mobilities, suggesting the presence of different prion strains within the State of Texas.
Conclusions: PMCA sensitivity is significantly higher than the current gold standards techniques IHC and ELISA and would be a good tool for rapid CWD screening.
Funded by: USDA
Grant number: AP20VSSPRS00C143
PRION 2022 ABSTRACTS, AND A BIG THANK YOU TO On behalf of the Prion2020/2022 Congress Organizing Committee and the NeuroPrion Association, we heartily invite you to join us for the International Conference Prion2020/2022 from 13.-16. September 2022 in Göttingen.
Prion 2022 Conference abstracts: pushing the boundaries
Shedding of Chronic Wasting Disease Prions in Multiple Excreta Throughout Disease Course in White-tailed Deer
Nathaniel D. Denkersa, Erin E. McNultya, Caitlyn N. Krafta, Amy V. Nallsa, Joseph A. Westricha, Wilfred Goldmannb, Candace K. Mathiasona, and Edward A. Hoovera
aPrion Research Center, College of Veterinary Medicine and Biological Sciences, Department of Microbiology, Immunology, and Pathology; Colorado State University, Fort Collins, CO, USA; bDivision of Infection and Immunity, The Roslin Institute and the Royal Dick School of Veterinary Studies, University of Edinburgh, Midlothian, UK
Aims: Chronic wasting disease (CWD) now infects cervids in South Korea, North America, and Scandinavia. CWD is unique in its efficient transmission and shedding of prions in body fluids throughout long course infections. Questions remain as to the magnitude of shedding and the route of prion acquisition. As CWD continues to expand, the need to better understand these facets of disease becomes more pertinent. The purpose of the studies described was to define the longitudinal shedding profile of CWD prions in urine, saliva, and feces throughout the course of infection in white-tailed deer.
Material and Methods: Twelve (12) white-tailed deer were inoculated with either 1 mg or 300ng of CWD. Urine, saliva, and feces were collected every 3-month post-inoculation (MPI) throughout the study duration. Cohorts were established based on PNRP genotype: codon 96 GG (n = 6) and alternate codons 96 GS (n = 5) & 103NT (n = 1). Urine and saliva were analyzed using iron-oxide magnetic extraction (IOME) and real-time quaking induced conversion (RT-QuIC)(IQ). Feces were subjected to IOME, followed by 4 rounds protein misfolding cyclic amplification (PMCA) with products analyzed by RT-QuIC (IPQ). To determine whether IPQ may be superior to IQ, a subset of urine and saliva were also tested by IPQ. Results were compared with clinical disease status.
Results: Within the 96 GG cohort, positive seeding activity was detected in feces from all deer (100%), in saliva from 5 of 6 (83%), and in urine from 4 of 6 (66%). Shedding in all excreta occurred at, or just after, the first positive tonsil biopsy result. In the 96 GS/103NT cohort, positive seeding activity could be detected in feces from 3 of 6 (50%) deer, saliva in 2 of 6 (33%), and urine in 1 of 6 (16%). Shedding in excreta was detected >5 months after the first tonsil positive result. Four of six 96 GG deer developed clinical signs of CWD, whereas only 2 of the 96 GS/103NT did. Shedding was more frequently detected in deer with clinical disease. The IPQ protocol did not significantly improve detection in saliva or urine samples, however, it significantly augmented detection in feces by eliminating non-specific background commonly experienced with IQ. Negative control samples remained negative in samples tested.
Conclusions: These studies demonstrate: (a) CWD prion excretion occurs throughout infection; (2) PRNP genotype (GG≫GS/NT) influences the excreta shedding; and (3) detection sensitivity in excreta can vary with different RT-QuIC protocols. These results provide a more complete perspective of prion shedding in deer during the course of CWD infection.
Funded by: National Institutes of Health (NIH)
Grant number: RO1-NS061902-09 R to EAH, PO1-AI077774 to EAH, and R01-AI112956-06 to CKM
Acknowledgement: We abundantly thank Sallie Dahmes at WASCO and David Osborn and Gino D’Angelo at the University of Georgia Warnell School of Forestry and Natural Resources for their long-standing support of this work through provision of the hand-raised, CWD-free, white-tailed deer used in these studies
Carrot plants as potential vectors for CWD transmission
Paulina Sotoa,b, Francisca Bravo-Risia,b, Claudio Sotoa, and Rodrigo Moralesa,b
aDepartment of Neurology, McGovern Medical School, University of Texas Health Science Center at Houston, Texas, USA; bUniversidad Bernardo O’Higgins, Santiago, Chile
Prion diseases are infectious neurodegenerative disorders afflicting humans and other mammals. These diseases are generated by the misfolding of the cellular prion protein into a disease-causing isoform. Chronic wasting disease (CWD) is a prevalent prion disease affecting cervids (captive and free-range). CWD is thought to be transmitted through direct animal contact or by indirect exposure to contaminated environments. Many studies have shown that infectious prions can enter the environment through saliva, feces, or urine from infected animals and decaying carcasses. However, we do not fully understand the specific contribution of each component to disease transmission events. Plants are logical environmental components to be evaluated since they grow in environments contaminated with CWD prions and are relevant for animal and human nutrition.
Aims: The main objective of this study is to study whether prions are transported to the roots and leaves of carrots, an edible plant commonly used in the human diet and as deer bait.
Methods: We have grown carrot plants in CWD-infected soils. After 90 days, we harvested the carrots and separated them from the leaves. The experiment was controlled by growing plants in soil samples treated with brain extracts from healthy animals. These materials were interrogated for their prion seeding activity using the Protein Misfolding Cyclic Amplification (PMCA) technique. Infectivity was evaluated in mouse bioassays (intracerebral injections in Tg1536 mice). The animals were sacrificed when they showed established signs of prion disease. Animals not displaying clinical signs were sacrificed at 600 days post-inoculation.
Results: The PMCA analysis demonstrated CWD seeding activity in soils contaminated with CWD prions, as well as in carrot plants (leaves and roots) grown on them. Bioassays demonstrated that both leaves and roots contained CWD prions in sufficient quantities to induce disease (92% attack rate). As expected, animals treated with prion-infected soils developed prion disease at shorter incubation periods (and complete attack rates) compared to plant components. Animals treated with soil and plant components exposed with CWD-free brain extracts did not display prion-associated clinical signs or evidence of sub-clinical prion infection.
Conclusions: We show that edible plant components can absorb prions from CWD contaminated soils and transport them to their aerial parts. Our results indicate that plants could participate as vectors of CWD transmission. Importantly, plants designated for human consumption represent a risk of introducing CWD prions into the human food chain.
Funded by: NIH
Grant number: R01AI132695
October 6th-12th, 126th Meeting 2022 Resolutions
RESOLUTION NUMBER: 30 Approved
SOURCE: COMMITTEE ON WILDLIFE
SUBJECT MATTER: Chronic Wasting Disease Carcass Disposal Dumpster Management and Biosecurity
BACKGROUND INFORMATION:
State and tribal wildlife agencies may identify collection points (dumpsters) within an identified chronic wasting disease (CWD) management zone for the disposal of hunter-harvested cervid carcasses to remove potentially infected carcasses off the landscape for disposal by an approved method (Gillin & Mawdsley, 2018, chap.14). However, depending on their placement and maintenance these dumpsters could potentially increase the risk of CWD transmission.
In several different states, photographic evidence has shown dumpsters in state identified CWD management zones overflowing with deer carcasses and limbs scattered on the land nearby. This could provide an opportunity for scavengers to potentially move infected carcass material to non-infected zones or increase contamination of the ground material around the dumpster’s location.
Federal guidance does not explicitly address uniform standards for collection locations for carcasses of free-ranging cervids; however, the United States Department of Agriculture, Animal and Plant Health Inspection Service, Veterinary Services Program Standards on CWD outlines procedures for carcass disposal, equipment sanitation, and decontamination of premises for captive cervid facilities.
RESOLUTION:
The United States Animal Health Association urges the Association of Fish and Wildlife Agencies (AFWA), Wildlife Health Committee to further refine the AFWA Technical Report on Best Management Practices for Prevention, Surveillance, and Management of Chronic Wasting Disease; Chapter 14, Carcass Disposal to address the placement and management of chronic wasting disease carcass disposal dumpsters or other carcass collection containers.
Reference:
1. Gillin, Colin M., and Mawdsley, Jonathan R. (eds.). 2018. AFWA Technical Report on Best Management Practices for Surveillance, Management and Control of Chronic Wasting Disease. Association of Fish and Wildlife Agencies, Washington, D. C. 111 pp.
Trucking CWD TSE PrP
Friday, December 14, 2012
DEFRA U.K. What is the risk of Chronic Wasting Disease CWD being introduced into Great Britain? A Qualitative Risk Assessment October 2012
snip...
The rate of transmission of CWD has been reported to be as high as 30% and can approach 100% among captive animals in endemic areas (Safar et al., 2008).
snip...
In summary, in endemic areas, there is a medium probability that the soil and surrounding environment is contaminated with CWD prions and in a bioavailable form. In rural areas where CWD has not been reported and deer are present, there is a greater than negligible risk the soil is contaminated with CWD prion.
snip...
In summary, given the volume of tourists, hunters and servicemen moving between GB and North America, the probability of at least one person travelling to/from a CWD affected area and, in doing so, contaminating their clothing, footwear and/or equipment prior to arriving in GB is greater than negligible. For deer hunters, specifically, the risk is likely to be greater given the increased contact with deer and their environment. However, there is significant uncertainty associated with these estimates.
snip...
Therefore, it is considered that farmed and park deer may have a higher probability of exposure to CWD transferred to the environment than wild deer given the restricted habitat range and higher frequency of contact with tourists and returning GB residents.
snip...
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
Prions in Waterways
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
“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.”
TUESDAY, JANUARY 16, 2024
CIDRAP launches international effort to prepare for possible chronic wasting disease spillover
Chronic Wasting Disease CWD TSE Prion Spillover to other Species, What If?
CWD, Plants, oh my…
***> Price of TSE Prion Poker goes up substantially, all you cattle ranchers and such, better pay close attention here...terry
Prion Conference 2023
Transmission of the chronic wasting disease agent from elk to cattle after oronasal exposure
Justin Greenlee, Jifeng Bian, Zoe Lambert, Alexis Frese, and Eric Cassmann Virus and Prion Research Unit, National Animal Disease Center, USDA-ARS, Ames, IA, USA
Aims: The purpose of this study was to determine the susceptibility of cattle to chronic wasting disease agent from elk.
Materials and Methods: Initial studies were conducted in bovinized mice using inoculum derived from elk with various genotypes at codon 132 (MM, LM, LL). Based upon attack rates, inoculum (10% w/v brain homogenate) from an LM132 elk was selected for transmission studies in cattle. At approximately 2 weeks of age, one wild type steer (EE211) and one steer with the E211K polymorphism (EK211) were fed 1 mL of brain homogenate in a quart of milk replacer while another 1 mL was instilled intranasally. The cattle were examined daily for clinical signs for the duration of the experiment. One steer is still under observation at 71 months post-inoculation (mpi).
Results: Inoculum derived from MM132 elk resulted in similar attack rates and incubation periods in mice expressing wild type or K211 bovine PRNP, 35% at 531 days post inoculation (dpi) and 27% at 448 dpi, respectively. Inoculum from LM132 elk had a slightly higher attack rates in mice: 45% (693 dpi) in wild type cattle PRNP and 33% (468) in K211 mice. Inoculum from LL132 elk resulted in the highest attack rate in wild type bovinized mice (53% at 625 dpi), but no K211 mice were affected at >700 days. At approximately 70 mpi, the EK211 genotype steer developed clinical signs suggestive of prion disease, depression, low head carriage, hypersalivation, and ataxia, and was necropsied. Enzyme immunoassay (IDEXX) was positive in brainstem (OD=4.00, but non-detect in retropharyngeal lymph nodes and palatine tonsil. Immunoreactivity was largely limited to the brainstem, midbrain, and cervical spinal cord with a pattern that was primarily glia-associated.
Conclusions: Cattle with the E211K polymorphism are susceptible to the CWD agent after oronasal exposure of 0.2 g of infectious material.
"Cattle with the E211K polymorphism are susceptible to the CWD agent after oronasal exposure of 0.2 g of infectious material."
=====end
Strain characterization of chronic wasting disease in bovine-PrP transgenic mice
Conclusions: Altogether, these results exhibit the diversity of CWD strains present in the panel of CWD isolates and the ability of at least some CWD isolates to infect bovine species. Cattle being one of the most important farming species, this ability represents a potential threat to both animal and human health, and consequently deserves further study.
"Altogether, these results exhibit the diversity of CWD strains present in the panel of CWD isolates and the ability of at least some CWD isolates to infect bovine species. Cattle being one of the most important farming species, this ability represents a potential threat to both animal and human health, and consequently deserves further study."
=====end
Cattle with the EK211 PRNP polymorphism are susceptible to the H-type bovine spongiform encephalopathy agent from either E211K or wild type donors after oronasal inoculation
Justin J. Greenleea, Eric D. Cassmanna, S. Jo Moorea,b, and M. Heather West Greenleec
aVirus and Prion Research Unit, National Animal Disease Center, ARS, United States Department of Agriculture, Ames, IA, USA; bOak Ridge Institute for Science and Education (ORISE), U.S. Department of Energy, Oak Ridge, TN, US; cDepartment of Biomedical Sciences, Iowa State University College of Veterinary Medicine, Ames, IA, US
Aims: In 2006, a case of H-type bovine spongiform encephalopathy (H-BSE) was reported in a cow with a previously unreported prion protein polymorphism (E211K). The E211K polymorphism is heritable and homologous to the E200K mutation in humans that is the most frequent PRNP mutation associated with familial Creutzfeldt-Jakob disease. Although the prevalence of the E211K polymorphism is low, cattle carrying the K211 allele develop H-type BSE with a rapid onset after experimental inoculation by the intracranial route. The purpose of this study was to investigate whether the agents of H-type BSE or H-type BSE associated with the E211K polymorphism transmit to wild type cattle or cattle with the K211 allele after oronasal exposure.
Material and Methods: Wild type (EE211) or heterozygous (EK211) cattle were oronasally inoculated with the H-BSE agent from either the US 2004 case (wild type donor; n = 3) or from the US 2006 case with the E211K polymorphism (n = 4). Cattle were observed daily throughout the course of the experiment for the development of clinical signs. When signs were noted, animals were euthanized and necropsied. Cattle were confirmed positive for abnormal BSE prions by enzyme immunoassay (EIA; Idexx HerdChek BSE Ag Test), anti-PrP immunohistochemistry (IHC) on brainstem, and microscopic examination for vacuolation.
Results: Three-out-of-four (75%) calves with the EK211 genotype developed clinical signs of H-BSE including inattentiveness, loss of body condition, weakness, ataxia, and muscle fasciculations and were euthanized. Two of the positive EK211 steers received H-BSE US 2004 inoculum (Incubation Period (IP): 59.3 and 72.3 months) while the other positive steer received the E211K H-BSE inoculum (IP: 49.7 months). EIA confirmed that abundant misfolded protein (O.D. 2.57–4.0) in the brainstem, and IHC demonstrated PrPScthroughout the brain. All wild type recipient cattle and a single EK211 steer remained asymptomatic for the duration of the experiment (approximately 7 years post-inoculation) and no abnormal prion protein was detected in these cattle by EIA.
Conclusions: This study demonstrates that the H-type BSE agent is transmissible by the oronasal route. Cattle with the EK211 genotype are oronasally susceptible to small doses of the H-BSE agent from either EK211 or EE211 (wild type) donors. Wild-type EE211 cattle remained asymptomatic for the duration of the experiment with this small dose (0.1 g) of inoculum. These results reinforce the need for ongoing surveillance for classical and atypical BSE to minimize the risk of potentially infectious tissues entering the animal or human food chains.
Funded by: US Department of Agriculture
CWD Deer Herd Population Declines
CWD poses a significant threat to the future of hunting in Texas. Deer population declines of 45 and 50 percent have been documented in Colorado and Wyoming. A broad infection of Texas deer populations resulting in similar population impacts would inflict severe economic damage to rural communities and could negatively impact land markets. Specifically, those landowners seeking to establish a thriving herd of deer could avoid buying in areas with confirmed CWD infections. As they do with anthrax-susceptible properties, land brokers may find it advisable to inquire about the status of CWD infections on properties that they present for sale. Prospective buyers should also investigate the status of the wildlife on prospective properties. In addition, existing landowners should monitor developments as TPWD crafts management strategies to identify and contain this deadly disease.
Dr. Gilliland (c-gilliland@tamu.edu) is a research economist with the Texas Real Estate Research Center at Texas A&M University.
Colorado CWD TSE Prion Detected in 40 of 54 deer herds, 17 of 42 elk herds, and 2 of 9 moose herds
Colorado CWD figures just out; COLORADO CWD UPDATE
Notably, prevalence in the White River herd, one of the state’s largest, rose from 15.3% to 23.6%.
Prevalence increased by about 10%, to 14%, in the Uncompahgre herd, and grew from 3.5% to 8% in the Middle Park herd.
Prevalence fell from 13.6% to 6.7% in the Sweetwater herd and from 12% to 8% in the Big Thompson herd.
Parks and Wildlife has detected the disease in 40 of Colorado’s 54 deer herds, 17 of its 42 elk herds and two of its nine moose herds.
Colorado Chronic Wasting Disease Response Plan December 2018.
Executive Summary Mule deer, white-tailed deer, elk and moose are highly valued species in North America. Some of Colorado’s herds of these species are increasingly becoming infected with chronic wasting disease(CWD).
As of July 2018, at least 31 of Colorado's 54 deer herds (57%), 16 of43 elk herds (37%), and 2 of 9 moose herds (22%) are known to be infected with CWD.
Four of Colorado's 5 largest deer herds and 2 of the state’s 5 largest elk herds are infected.
Deer herds tend to be more heavily infected than elk and moose herds living in the same geographic area.
Not only are the number of infected herds increasing, the past 15 years of disease trends generally show an increase in the proportion of infected animals within herds as well.
Of most concern, greater than a 10-fold increase in CWD prevalence has been estimated in some mule deer herds since the early 2000s; CWD is now adversely affecting the performance of these herds.
snip...(the map on page 71, cwd marked in red, is shocking...tss)
Since identifying its first cases of CWD in captive deer in the 70s and finding the first wild infected deer in 1985, Wyoming has seen the disease slowly spread throughout the state. CWD has now been documented in members of the deer family in most of Wyoming’s deer hunting areas, with 20% to 40% percent of mule deer affected in some herds. A 2017 study estimated a 21% annual population decline as a result of the fatal disease.
How does CWD impact deer, elk, and moose populations?
Recent research in Wyoming has demonstrated declines in both mule and white-tailed deer populations in deer hunt area 65 due to CWD (see below for citations). These declines are in the core endemic area where prevalence is highest. In areas with lower prevalence, effects of CWD are poorly understood but are considered additive along with other factors that can negatively affect deer populations in Wyoming (i.e. habitat loss, predation, other diseases). The distribution and prevalence of CWD in Wyoming elk is less than that of deer. Currently there are no documented direct population impacts in Wyoming elk from CWD; however, research from Rocky Mountain National Park suggests that CWD could impact elk populations at higher prevalence (13%). While CWD has been found in free ranging moose, there have been few detections, and there is no evidence that CWD is currently having an impact on moose populations.
WYOMING, POWELL — Sobering news resulting from a multi-year Chronic Wasting Disease (CWD) surveillance program by the Wyoming Game and Fish Department between 2018 and 2022 shows significant increases in the fatal disease for the state’s prized mule deer and elk herds.
In one herd, the prevalence rate is calculated at 65% in mule deer bucks, and there are concerning increases in infected elk, including hunt areas popular for Big Horn Basin hunters.
The disease, which typically kills infected animals within two years after initial exposure, now occurs in 34 of Wyoming’s 37 mule deer herds, and 15 of the state’s 36 elk herd units.
Control of Chronic Wasting Disease OMB Control Number: 0579-0189APHIS-2021-0004 Singeltary Submission
https://www.regulations.gov/comment/APHIS-2021-0004-0002
https://downloads.regulations.gov/APHIS-2021-0004-0002/attachment_1.pdf
Docket No. APHIS-2018-0011 Chronic Wasting Disease Herd Certification
https://www.regulations.gov/document/APHIS-2018-0011-0003
https://downloads.regulations.gov/APHIS-2018-0011-0003/attachment_1.pdf
APHIS Indemnity Regulations [Docket No. APHIS-2021-0010] RIN 0579-AE65 Singeltary Comment Submission
Comment from Singeltary Sr., Terry
Posted by the Animal and Plant Health Inspection Service on Sep 8, 2022
https://www.regulations.gov/comment/APHIS-2021-0010-0003
https://downloads.regulations.gov/APHIS-2021-0010-0003/attachment_1.pdf
Docket No. FDA-2003-D-0432 (formerly 03D-0186) Use of Material from Deer and Elk in Animal Feed
PUBLIC SUBMISSION
Comment from Terry Singeltary Sr.
Posted by the Food and Drug Administration on May 17, 2016 Comment
Docket No. FDA-2003-D-0432 (formerly 03D-0186) Use of Material from Deer and Elk in Animal Feed Singeltary Submission
https://www.regulations.gov/comment/FDA-2003-D-0432-0011
https://www.regulations.gov/docket/FDA-2003-D-0432
Tennessee State Veterinarian Alerts Cattle Owners to Disease Detection Mad Cow atypical L-Type BSE
Friday, May 19, 2023 | 04:12pm NASHVILLE — The Tennessee State Veterinarian is confirming a case of atypical bovine spongiform encephalopathy (BSE) in a cow with ties to Tennessee.
The cow appeared unwell after arriving at a packing company in South Carolina. In alignment with the United States Department of Agriculture’s BSE surveillance program, the animal was isolated and euthanized. It did not enter the food supply. Preliminary investigation has determined the cow originated in southeast Tennessee.
“We are working closely with our federal partners and animal health officials in South Carolina for this response,” State Veterinarian Dr. Samantha Beaty said. “That includes determining prior owners and locations where the affected cow lived in Tennessee and tracing siblings and offspring for testing.”
BSE is a chronic degenerative disease affecting the central nervous system of cattle. It is caused by an abnormal prion protein. The atypical form occurs spontaneously at very low levels in all cattle populations, particularly in older animals. Atypical BSE poses no known risk to human health. It is different from the classical form of BSE, which has not been detected in the U.S. since 2003.
BSE is not contagious and therefore is not spread through contact between cattle or with other species. There is no treatment for or vaccine to prevent BSE. The U.S. has a strong surveillance program in place for early detection and to prevent suspect cattle from entering the food supply chain.
Cattle owners are always advised to monitor their herds for health. Cattle affected by BSE may display changes in temperament, abnormal posture, poor coordination, decreased milk production, or loss of condition without noticeable loss of appetite. Owners should report any herd health concerns to their veterinarian or to the State Veterinarian’s office at 615-837-5120.
The Tennessee Department of Agriculture Animal Health Division is responsible for promoting animal health in Tennessee. The State Veterinarian’s office seeks to prevent the spread of disease through import and movement requirements, livestock traceability, disaster mitigation, and the services of the C.E. Kord Animal Health Diagnostic Laboratory. The division collaborates with other health-related stakeholders, academic institutions, and extension services to support One Health, an initiative to improve health for people and animals.
USDA Announces Atypical L-Type Bovine Spongiform Encephalopathy BSE Detection
The U.S. Department of Agriculture (USDA) is announcing an atypical case of Bovine Spongiform Encephalopathy (BSE), a neurologic disease of cattle, in an approximately five-year-old or older beef cow at a slaughter plant in South Carolina. This animal never entered slaughter channels and at no time presented a risk to the food supply or to human health in the United States. Given the United States’ negligible risk status for BSE, we do not expect any trade impacts as a result of this finding.
USDA Animal and Plant Health Inspection Service’s (APHIS) National Veterinary Services Laboratories (NVSL) confirmed that this cow was positive for atypical L-type BSE. The animal was tested as part of APHIS’s routine surveillance of cattle that are deemed unsuitable for slaughter. The radio frequency identification tag present on the animal is associated with a herd in Tennessee. APHIS and veterinary officials in South Carolina and Tennessee are gathering more information during this ongoing investigation.
Atypical BSE generally occurs in older cattle and seems to arise rarely and spontaneously in all cattle populations.
This is the nation’s 7th detection of BSE. Of the six previous U.S. cases, the first, in 2003, was a case of classical BSE in a cow imported from Canada; the rest have been atypical (H- or L-type) BSE.
The World Organization for Animal Health (WOAH) recognizes the United States as negligible risk for BSE. As noted in the WOAH guidelines for determining this status, atypical BSE cases do not impact official BSE risk status recognition as this form of the disease is believed to occur spontaneously in all cattle populations at a very low rate. Therefore, this finding of an atypical case will not change the negligible risk status of the United States, and should not lead to any trade issues.
The United States has a longstanding system of interlocking safeguards against BSE that protects public and animal health in the United States, the most important of which is the removal of specified risk materials - or the parts of an animal that would contain BSE should an animal have the disease - from all animals presented for slaughter. The second safeguard is a strong feed ban that protects cattle from the disease. Another important component of our system - which led to this detection - is our ongoing BSE surveillance program that allows USDA to detect the disease if it exists at very low levels in the U.S. cattle population.
More information about this disease is available in the BSE factsheet.
#
https://www.aphis.usda.gov/aphis/newsroom/stakeholder-info/sa_by_date/sa-2023/bse
May 2, 2023
Docket No. APHIS–2023–0027 Notice of Request for Revision to and Extension of Approval of an Information Collection; National Veterinary Services Laboratories; Bovine Spongiform Encephalopathy Surveillance Program Singeltary Submission
ONLY by the Grace of God, have we not had a documented BSE outbreak, that and the fact the USDA et al are only testing 25K cattle for BSE, a number too low to find mad cow disease from some 28.9 million beef cows in the United States as of Jan. 1, 2023, down 4% from last year. The number of milk cows in the United States increased to 9.40 million. U.S. calf crop was estimated at 34.5 million head, down 2% from 2021. Jan 31, 2023.
ALL it would take is one BSE positive, yet alone a handful of BSE cases, this is why the Enhanced BSE was shut down, and the BSE testing shut down to 25k, and the BSE GBRs were replaced with BSE MRRs, after the 2003 Christmas Mad cow, the cow that stole Christmas, making it legal to trade BSE, imo.
Document APHIS-2023-0027-0001 BSE Singeltary Comment Submission
https://www.regulations.gov/comment/APHIS-2023-0027-0002
see full submission;
https://downloads.regulations.gov/APHIS-2023-0027-0002/attachment_1.pdf
NOW before you go off and start repeating BSE TSE Prion science that is almost 50 years old, let's be perfectly clear what science is saying today, and especially what the WAHIS/WOAH/OIE et al are saying about the atypical BSE strains... OIE Conclusions on transmissibility of atypical BSE among cattle
Given that cattle have been successfully infected by the oral route, at least for L-BSE, it is reasonable to conclude that atypical BSE is potentially capable of being recycled in a cattle population if cattle are exposed to contaminated feed. In addition, based on reports of atypical BSE from several countries that have not had C-BSE, it appears likely that atypical BSE would arise as a spontaneous disease in any country, albeit at a very low incidence in old cattle. In the presence of livestock industry practices that would allow it to be recycled in the cattle feed chain, it is likely that some level of exposure and transmission may occur. As a result, since atypical BSE can be reasonably considered to pose a potential background level of risk for any country with cattle, the recycling of both classical and atypical strains in the cattle and broader ruminant populations should be avoided.
Annex 7 (contd) AHG on BSE risk assessment and surveillance/March 2019
34 Scientific Commission/September 2019
3. Atypical BSE
The Group discussed and endorsed with minor revisions an overview of relevant literature on the risk of atypical BSE being recycled in a cattle population and its zoonotic potential that had been prepared ahead of the meeting by one expert from the Group. This overview is provided as Appendix IV and its main conclusions are outlined below. With regard to the risk of recycling of atypical BSE, recently published research confirmed that the L-type BSE prion (a type of atypical BSE prion) may be orally transmitted to calves1 . In light of this evidence, and the likelihood that atypical BSE could arise as a spontaneous disease in any country, albeit at a very low incidence, the Group was of the opinion that it would be reasonable to conclude that atypical BSE is potentially capable of being recycled in a cattle population if cattle were to be exposed to contaminated feed. Therefore, the recycling of atypical strains in cattle and broader ruminant populations should be avoided.
4. Definitions of meat-and-bone meal (MBM) and greaves
http://web.oie.int/downld/PROC2020/A_SCAD_Sept2019.pdf
Consumption of L-BSE–contaminated feed may pose a risk for oral transmission of the disease agent to cattle.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5324790/
Thus, it is imperative to maintain measures that prevent the entry of tissues from cattle possibly infected with the agent of L-BSE into the food chain.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3310119/
''H-TYPE BSE AGENT IS TRANSMISSIBLE BY THE ORONASAL ROUTE''
This study demonstrates that the H-type BSE agent is transmissible by the oronasal route. These results reinforce the need for ongoing surveillance for classical and atypical BSE to minimize the risk of potentially infectious tissues entering the animal or human food chains.
https://www.ars.usda.gov/research/publications/publication/?seqNo115=353094
Bovine Spongiform Encephalopathy BSE TSE Prion Origin USA?, what if?
Research Project: Pathobiology, Genetics, and Detection of Transmissible Spongiform Encephalopathies Location: Virus and Prion Research
Title: Sheep are susceptible to the agent of TME by intracranial inoculation and have evidence of infectivity in lymphoid tissues
Author item CASSMANN, ERIC - Oak Ridge Institute For Science And Education (ORISE) item MOORE, SARA - Oak Ridge Institute For Science And Education (ORISE) item SMITH, JODI - Iowa State University item Greenlee, Justin
Submitted to: Frontiers in Veterinary Science Publication Type: Peer Reviewed Journal Publication Acceptance Date: 11/14/2019 Publication Date: 11/29/2019 Citation: Cassmann, E.D., Moore, S.J., Smith, J.D., Greenlee, J.J. 2019.
Sheep are susceptible to the agent of TME by intracranial inoculation and have evidence of infectivity in lymphoid tissues.
Frontiers in Veterinary Science. 6:430. https://doi.org/10.3389/fvets.2019.00430. DOI: https://doi.org/10.3389/fvets.2019.00430
Interpretive Summary: Prion diseases are protein misfolding diseases that are transmissible between animals. The outcome of prion infection is irreversible brain damage and death. Transmission can occur between animals of the same or different species, however, transmission between different species is usually less efficient due to the species barrier, which results from differences in the amino acid sequence of the prion protein between the donor and recipient species. The present work evaluated whether transmissible mink encephalopathy (TME) can infect sheep. Our results demonstrate that sheep are susceptible to the TME agent and that the TME agent has similar properties to the agent of L-type atypical bovine spongiform encephalopathy (L-BSE). This work supports the ideas that L-BSE is a possible source for TME in mink and that the practice of feeding cattle with neurologic disease to mink should be avoided. This information is important to farmers who raise cattle, sheep, or mink.
Technical Abstract: Transmissible mink encephalopathy (TME) is a food borne prion disease. Epidemiological and experimental evidence suggests similarities between the agent of TME and L-BSE. This experiment demonstrates the susceptibility of four different genotypes of sheep to the agent of TME by intracranial inoculation. The four genotypes of sheep used in this experiment had polymorphisms corresponding to codons 136 and 171 of the prion gene: VV136QQ171, AV136QQ171, AA136QQ171, and AA136QR171. All intracranially inoculated sheep without comorbidities (15/15) developed clinical scrapie and had detectable PrPSc by immunohistochemistry, western blot, and enzyme immunoassay (EIA). The mean incubation periods in TME infected sheep correlated with their relative genotypic susceptibility. There was peripheral distribution of PrPSc in the trigeminal ganglion and neuromuscular spindles; however, unlike classical scrapie and C-BSE in sheep, ovine TME did not accumulate in the lymphoid tissue. To rule out the presence of infectious, but proteinase K susceptible PrPSc, the lymph nodes of two sheep genotypes, VV136QQ171 and AA136QQ171, were bioassayed in transgenic ovinized mice. None of the mice (0/32) inoculated by the intraperitoneal route had detectable PrPSc by EIA. Interestingly, mice intracranially inoculated with RPLN tissue from a VV136QQ171 sheep were EIA positive (3/17) indicating that sheep inoculated with TME harbor infectivity in their lymph nodes. Western blot analysis demonstrated similarities in the migration patterns between ovine TME and the bovine TME inoculum. Overall, these results demonstrate that sheep are susceptible to the agent of TME, and that the tissue distribution of PrPSc in TME infected sheep is distinct from classical scrapie.
https://www.ars.usda.gov/research/publications/publication/?seqNo115=363305
https://www.ars.usda.gov/research/publications/publication/?seqNo115=360665
https://www.ars.usda.gov/research/publications/publication/?seqNo115=373668
Previous work has shown that the Stetsonville, WI outbreak of TME could have been precipitated by feeding mink a downer cow with atypical BSE; therefore, it very well may have originated from a cow with L-BSE. The agent of TME appears to remain stable, and it has a high transmission efficiency after a sequence of interspecies transmission events. Although C-BSE is the archetypal foodborne TSE, our findings indicate that L-BSE and bTME have greater transmission efficiencies in bovinized mice. Previous work has demonstrated that L-BSE also is more virulent than C-BSE in mice expressing the human prion protein [46, 55]. Although the documented incidence of L-BSE is low, the propensity of L-BSE and the TME agent to cross species barriers support the continued monitoring for atypical BSE.
https://bmcvetres.biomedcentral.com/articles/10.1186/s12917-020-02611-0
***>This work supports the ideas that L-BSE is a possible source for TME in mink and that the practice of feeding cattle with neurologic disease to mink should be avoided. This information is important to farmers who raise cattle, sheep, or mink.<***
1985
Evidence That Transmissible Mink Encephalopathy Results from Feeding Infected Cattle Over the next 8-10 weeks, approximately 40% of all the adult mink on the farm died from TME.
snip...
The rancher was a ''dead stock'' feeder using mostly (>95%) downer or dead dairy cattle...
https://web.archive.org/web/20090506002258/http://www.bseinquiry.gov.uk/files/mb/m09/tab05.pdf
https://web.archive.org/web/20090506001031/http://www.bseinquiry.gov.uk/files/mb/m09a/tab01.pdf
Specified Risk Materials DOCKET NUMBER Docket No. FSIS-2022-0027 Singeltary Submission Attachment
https://www.regulations.gov/comment/FSIS-2022-0027-0002
https://downloads.regulations.gov/FSIS-2022-0027-0002/attachment_1.pdf
Title: Bovine adapted transmissible mink encephalopathy is similar to L-BSE after passage through sheep with the VRQ/VRQ genotype but not VRQ/ARQ
Author Cassmann, Eric MOORE, SARA, J, SARA - Orise Fellow KOKEMULLAR, ROBYN - Non ARS Employee BALKEMA-BUSCHMAN, A - Friedrich-Loeffler-institute GROSCHUP, M - Friedrich-Loeffler-institut Nicholson, Eric Greenlee, Justin
Submitted to: BMC Veterinary Research Publication Type: Peer Reviewed Journal Publication Acceptance Date: 10/2/2020 Publication Date: 10/8/2020
Citation: Cassmann, E.D., Moore, Sara, J, S.J., Kokemullar, R.D., Balkema-Buschman, A., Groschup, M., Nicholson, E.M., Greenlee, J.J. 2020. Bovine adapted transmissible mink encephalopathy is similar to L-BSE after passage through sheep with the VRQ/VRQ genotype but not VRQ/ARQ. BMC Veterinary Research. 16. Article 383. https://doi.org/10.1186/s12917-020-02611-0.
DOI: https://doi.org/10.1186/s12917-020-02611-0
Interpretive Summary: Transmissible spongiform encephalopathies (TSEs), or prion diseases, are fatal brain diseases that affect livestock species. A prion disease of cattle known as Mad Cow Disease, or classical bovine spongiform encephalopathy (C-BSE), broke out in the UK from 1986-1998. The disease affected millions of cattle and over 180,000 were confirmed positive. Food products from affected cattle that were consumed by humans led to a disease in people called variant Creutzfeldt-Jakob disease. Another example of cross-species transmission occurs in mink. Mink that are fed prion contaminated food results in a disease called transmissible mink encephalopathy (TME). The present study was designed to determine the effect of cross-species transmission of prion diseases in livestock on the ability to infect mice expressing the cattle prion protein. We found that passing cattle adapted TME prions from cattle to sheep changed the ability of the prions to infect mice. These results were compared to atypical BSE (L-BSE type) and Classical BSE. Depending on the genotype of sheep used, the disease in mice appeared similar to either L-BSE or C-BSE. These results indicate a shift in the disease outcome based on transmission through sheep with different genotypes. This information gives insight into the genesis of new prion strains. It also supports the hypothesis that TME can originate from feeding mink protein from cattle afflicted with L-BSE.
Technical Abstract: Transmissible mink encephalopathy (TME) is a fatal neurologic disease of farmed mink. Epidemiological and experimental evidence indicates that TME and L-BSE are similar and may be linked in some outbreaks of TME. We previously transmitted bovine adapted TME (bTME) to sheep; the present study compared ovine bTME (o-bTME) to C-BSE and L-BSE in transgenic mice expressing wild type bovine prion protein (TgBovXV). Sheep donor genotype elicited variable disease phenotypes in bovinized mice. Inoculum derived from a sheep with the VRQ/VRQ genotype (o-bTMEVV) resulted in an attack rate, incubation period, immunoblot profile, and neuropathology most similar to bTME and L-BSE. Conversely, sheep with the VRQ/ARQ genotype (o-bTMEAV) elicited a phenotype distinct from the bTME and L-BSE. Instead, o-bTMEAV led to a disease phenotype with partial similarity to C-BSE. To determine the transmission efficiency of all TSEs in this study, we considered attack rate, mean incubation period, and the relative quantity of PrPSc in the samples. The TSE with the highest transmission capability in bovinized mice was L-BSE. The tendency to efficiently transmit to TgBovXV mice decreased in the following order bTME, C-BSE, o-bTMEVV, and o-bTMEAV. The transmission efficiency of L-BSE was approximately 1.3 times higher than o-bTMEVV and 4 times higher than o-bTMEAV. Our findings provide insight on how sheep host genotype modulates strain genesis and influences interspecies transmission characteristics. Given the similarities between TME and L-BSE, their efficient interspecies transmission capabilities, and previous reports of L-BSE transmission to mice expressing the human prion protein, continued monitoring for atypical BSE is advisable in order to prevent occurrences of interspecies transmission that may affect humans or other species.
“Given the similarities between TME and L-BSE, their efficient interspecies transmission capabilities, and previous reports of L-BSE transmission to mice expressing the human prion protein, continued monitoring for atypical BSE is advisable in order to prevent occurrences of interspecies transmission that may affect humans or other species.”
https://www.ars.usda.gov/research/publications/publication/?seqNo115=373668
Wednesday, May 24, 2023
***> WAHIS, WOAH, OIE, United States of America Bovine spongiform encephalopathy Immediate notification
https://wahis.woah.org/#/in-review/5067
posted by Terry S. Singeltary Sr. at
2:36 PM
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