Friday, December 11, 2009

CWD, FECES, ORAL LESIONS, Aerosol and intranasal transmission

O.11.1

Prions in feces of asymptomatic deer

Gültekin Tamgüney1,2, Michael W. Miller3, Lisa L. Wolfe3, Tracey M. Sirochman3, David V. Glidden4, Christina Palmer 1, Azucena Lemus5, Stephen J. DeArmond5, Stanley B. Prusiner1,2

1Institute for Neurodegenerative Diseases, University of California, San Francisco, USA; 2Department of Neurology, University of California, San Francisco, USA; 3Colorado Division of Wildlife, Wildlife Research Center, Fort Collins, USA; 4Department of Epidemiology and Biostatistics, University of California, San Francisco, USA; 5Department of Pathology, University of California, San Francisco, USA

Background: Chronic wasting disease (CWD) of several species in the deer family and scrapie of sheep are infectious prion diseases that are transmitted naturally within affected host populations. Even though several potential sources of infectivity have been identified in secretions and excretions from symptomatic animals, the biological importance of these sources in sustaining epidemics remains unclear.

Objective/Methods: Feces from mule deer (Odocoileus hemionus) were periodically collected before and after oral inoculation with CWD prions until the deer developed clinical signs of CWD. Fecal samples were irradiated and intracerebrally inoculated into transgenic mice overexpressing cervid PrP.

Results: We report that asymptomatic CWD-infected mule deer excrete CWD prions in their feces long before they develop clinical signs of prion disease. Intracerebral inoculation of irradiated deer feces into transgenic mice overexpressing cervid PrP revealed infectivity in 14 of 15 fecal samples collected from 5 deer at 7–11 months before the onset of neurological disease. Even though prion concentrations in deer feces were much lower than those in brain tissue from the same deer collected at the disease terminus, the estimated total infectious dose excreted in feces by an infected deer over the disease course may approximate the total contained in brain tissue.

Discussion: Fecal prion excretion over long periods of time by infected deer provides a likely natural mechanism that may explain the high incidence and efficient horizontal transmission of CWD within deer herds, as well as prion transmission among susceptible cervid species.

Selected by the scientific committee from the submitted abstracts

P.4.27

Minor oral lesions facilitate CWD infection

Nathaniel Denkers1, Glenn Telling2, Edward Hoover1 1Colorado State University, USA; 2University of Kentucky, USA

Background: While the exact mechanisms of chronic wasting disease (CWD) prion transmission, entry, and trafficking remain incompletely elucidated, transmission by exposure of the oral and/or nasal mucous membranes seems certain. As part of foraging, cervids likely experience minor lesions in the oral mucous membranes; these could have impact on susceptibility to prion entry and subsequent infection.

Objectives: To explore this potential co-factor, we used cervid PrP transgenic mice to assess whether or not micro-abrasions to the tongue may enhance susceptibility to oral CWD infection. Methods: Two sets of FVB mice transgenically expressing the normal cervid PrPC protein [Tg(cerPrP) mice], with or without abrasions on the lingual mucosa, were inoculated orally with 10µl of a 10% w/v brain homogenate from either CWD-positive or negative deer. Abrasions were created by lightly scratching the dorsal lingual epithelium with a 30g needle. Cohorts were sacrificed at 1, 2, 12, 52, 78, and 104 weeks post inoculation (pi) or when signs of neurologic disease were observed. Tongue, lymphoid tissue, and the brain were assessed by western blotting and immunohistochemistry to detect the CWD abnormal prion protein (PrPCWD).

Results: Between 296 and 430 dpi, 8 of the 9 CWD-inoculated mice with lingual lesions developed clinical signs of neurologic dysfunction mandating euthanasia. The brains of all 8 mice were positive by western blot and immunohistochemistry for PrPCWD. Conversely, all mice without oral lesions remain asymptomatic at >450 dpi. No evidence of PrPCWD was detected in any Tg(cerPrP) mice examined at any of the preterminal time points.

Discussion: Micro-abrasions to the lingual surface substantially facilitate CWD transmission, suggesting a co-factor that may be significant in foraging cervids or other species. Earlier post-inoculation sampling intervals (1 and 4 hours) are in progress in an attempt to determine when and where PrPCWD might be detectable after oral mucosal exposure.

P.4.26

Aerosol and intranasal transmission of CWD

Nathaniel Denkers1, Glenn Telling2, Edward Hoover1 1Colorado State University, USA; 2University of Kentucky, USA

Background: Little is known regarding the potential risk posed by aerosolized prions. Chronic wasting disease (CWD) prions are present in saliva and urine of infected animals and it is clearly established that CWD is transmitted horizontally, almost surely by mucosal exposure. However, the potential transmissibility of CWD by aerosol or nasal routes is not known.

Objectives: The present study was therefore designed to determine whether CWD prions are transmissible by these routes of exposure using the cervid PrP transgenic mouse model of CWD infection.

Methods: FVB mice transgenically expressing the normal cervid PrPC protein [Tg(cerPrP) mice] were exposed to CWD prions by either nose-only exposure to an aerosol generated by nebulizing 0.5 ml of a 5% w/v CWD+ brain homogenate or 10µl of a 10% w/v CWD+ brain homogenate by dropwise instillation into the nostrils. Mice were monitored for signs of clinical disease for up to 755 days post inoculation (dpi). Nasal mucosa, vomeronasal organ, lymphoid tissue, and the brain were assessed for PrPCWD by western blotting and immunohistochemistry.

Results: Six of 7 aerosol-exposed Tg(cerPrP) mice developed clinical signs of neurologic dysfunction between 411 and 749 dpi mandating euthanasia. In all symptomatic mice CWD infection was confirmed by histopathologic lesions and detection of PrPCWD within the brain. Two of 9 IN-inoculated Tg(cerPrP) mice also developed TSE between 417 and 755 dpi, again confirmed by PrPCWD detection within the brain. No evidence of PrPCWD was detected in any Tg(cerPrP) mice examined at any of the pre-terminal time points.

Discussion: CWD is transmissible by aerosol as well as intranasal exposure¯potentially implicating exposure via the respiratory system in CWD and potentially other prion diseases. Studies examining very early post-inoculation sampling intervals (1 and 4 hours) are in progress in an attempt to determine initial prion targeting and entry portals.

Transmission and Pathogenesis 115

POSTERS


http://www.prion2009.com/





Sunday, December 06, 2009

Detection of Sub-Clinical CWD Infection in Conventional Test-Negative Deer Long after Oral Exposure to Urine and Feces from CWD+ Deer


http://chronic-wasting-disease.blogspot.com/2009/12/detection-of-sub-clinical-cwd-infection.html






http://chronic-wasting-disease.blogspot.com/




TSS

Labels: , , ,

Thursday, December 10, 2009

SOUTH DAKOTA'S CHRONIC WASTING DISEASE (CWD) TESTING UPDATE -2009

More CWD cases found in wildlife South Dakota


Associated Press - December 10, 2009 6:25 AM ET

PIERRE, S.D. (AP) - A half dozen cases of chronic wasting disease were found among 667 samples from deer and elk tested in South Dakota over a recent five-month period.

Chronic wasting attacks the brains of infected animals and is always fatal.

The Game, Fish and Parks Department said lab results are pending on another 477 samples taken between July and December.

The state has found 118 cases of chronic wasting disease since testing began in 1997. All infected animals were in the southwest corner of the state.

Copyright 2009 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.




http://www.ktiv.com/Global/story.asp?S=11653671





SOUTH DAKOTA'S CHRONIC WASTING DISEASE (CWD) TESTING UPDATE -2009


In the South Dakota CWD Surveillance period of July 1, 2009 to November 30, 2009 a total of 1,147 samples have been collected for CWD surveillance. Breakdown of the sampling is as follows:

303 elk sampled - 300 results returned as NOT Positive - 0 results pending (3 POSITIVE ELK FOUND)

246 mule deer sampled - 53 results returned as NOT Positive - 192 results pending (1 POSITIVE MD FOUND)

597 white-tailed deer - 310 results returned as NOT Positive - 285 results pending (2 POSITIVE WT FOUND)

1 Moose sampled--1 result returned as NOT Positive

Below is a listing of the Positive cervids that have been found in South Dakota during this surveillance period.

1. MD male from Rapid City Limits in Pennington County. (Sick/Surveillance) 2. WT female from Unit 27B in Fall River County. (Sick/Surveillance) 3. Elk male from Unit H4A in Custer County. (Hunter Harvest) 4. Elk male from Custer State Park in Custer County. (Hunter Harvest) 5. Elk female from Unit H3D in Custer County. (Hunter Harvest)

6. WT male from Black Hills Deer Unit BH1-11 Custer County (Hunter Harvest)

In Summary:

South Dakota is reporting a total of 6 positive cervids ( 3 elk, 3 deer).

To date, South Dakota has found 118 cases of CWD (78 deer and 40 elk) in free ranging deer and elk since testing began in 1997. Wind Cave National Park accounts for 29 of these animals (21 elk, 8 deer). Four elk and 1 deer have been found in Custer State Park. A total of 20,716 wild deer and elk have been tested for CWD since 1997.

Hunters may get their animal tested for chronic wasting disease by making their own arrangements directly through the SDSU Diagnostic Lab at (605) 688-5171.


http://www.sdgfp.info/Wildlife/hunting/BigGame/CWDresults.htm





CHRONIC WASTING DISEASE MANAGEMENT PLAN FOR FREE-RANGING DEER AND ELK IN SOUTH DAKOTA (Revised April 2006)


http://www.sdgfp.info/Wildlife/hunting/BigGame/CWDmanagementplan.htm




Map of CWD positives in Southwestern SD July 2008-May 2009


http://www.sdgfp.info/Wildlife/hunting/BigGame/Black%20Hills%2008-09.jpg




Black Hills view of Positive CWD cases in South Dakota, 2001-May 2009


http://www.sdgfp.info/Wildlife/hunting/BigGame/Black%20Hills%2001-09.jpg




Sunday, December 06, 2009

Detection of Sub-Clinical CWD Infection in Conventional Test-Negative Deer Long after Oral Exposure to Urine and Feces from CWD+ Deer


http://chronic-wasting-disease.blogspot.com/2009/12/detection-of-sub-clinical-cwd-infection.html





ALSO, NOTE MINERAL LICKS A POSSIBLE SOURCE AND TRANSMISSION MODE FOR CWD ;


http://chronic-wasting-disease.blogspot.com/2009/08/third-international-cwd-symposium-july.html




http://www.cwd-info.org/pdf/3rd_CWD_Symposium_utah.pdf



Detection of Protease-Resistant Prion Protein in Water from a CWD-Endemic Area Posted by Terry S. Singeltary Sr. on December 4, 2009 at 11:42am

65

Detection of Protease-Resistant Prion Protein in Water from a CWD-Endemic Area

Tracy A. Nichols*1,2, Bruce Pulford1, Christy Wyckoff1,2, Crystal Meyerett1, Brady Michel1, Kevin Gertig3, Jean E. Jewell4, Glenn C. Telling5 and M.D. Zabel1 1Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA 2National Wildlife Research Center, Wildlife Services, United States Department of Agriculture, Fort Collins, Colorado, 80521, USA 3Fort Collins Water and Treatment Operations, Fort Collins, Colorado, 80521, USA 4 Department of Veterinary Sciences, Wyoming State Veterinary Laboratory, University of Wyoming, Laramie, Wyoming, 82070, USA 5Department of Microbiology, Immunology, Molecular Genetics and Neurology, Sanders Brown Center on Aging, University of Kentucky, Lexington, Kentucky, 40536, USA * Corresponding author- tracy.a.nichols@aphis.usda.gov

Chronic wasting disease (CWD) is the only known transmissible spongiform encephalopathy affecting free-ranging wildlife. Experimental and epidemiological data indicate that CWD can be transmitted horizontally and via blood and saliva, although the exact mode of natural transmission remains unknown. Substantial evidence suggests that prions can persist in the environment, implicating it as a potential prion reservoir and transmission vehicle. CWD- positive animals can contribute to environmental prion load via biological materials including saliva, blood, urine and feces, shedding several times their body weight in possibly infectious excreta in their lifetime, as well as through decomposing carcasses. Sensitivity limitations of conventional assays hamper evaluation of environmental prion loads in water. Here we show the ability of serial protein misfolding cyclic amplification (sPMCA) to amplify minute amounts of CWD prions in spiked water samples at a 1:1 x106 , and protease-resistant prions in environmental and municipal-processing water samples from a CWD endemic area. Detection of CWD prions correlated with increased total organic carbon in water runoff from melting winter snowpack. These data suggest prolonged persistence and accumulation of prions in the environment that may promote CWD transmission.

snip...

The data presented here demonstrate that sPMCA can detect low levels of PrPCWD in the environment, corroborate previous biological and experimental data suggesting long term persistence of prions in the environment2,3 and imply that PrPCWD accumulation over time may contribute to transmission of CWD in areas where it has been endemic for decades. This work demonstrates the utility of sPMCA to evaluate other environmental water sources for PrPCWD, including smaller bodies of water such as vernal pools and wallows, where large numbers of cervids congregate and into which prions from infected animals may be shed and concentrated to infectious levels.

snip...end...full text at ;


http://www.landesbioscience.com/journals/prion/article/NicholsPRION...



http://www.cwd-info.org/pdf/3rd_CWD_Symposium_utah.pdf



http://chronic-wasting-disease.blogspot.com/2009/08/third-international-cwd-symposium-july.html



http://chronic-wasting-disease.blogspot.com/2009/10/detection-of-protease-resistant-cervid.html






AS THE CROW FLIES, SO DOES CWD



Sunday, November 01, 2009

American crows (Corvus brachyrhynchos) and potential spreading of CWD
through feces of digested infectious carcases


http://chronic-wasting-disease.blogspot.com/2009/11/american-crows-corvus-brachyrhynchos.html





Thursday, September 10, 2009

Experimental oral transmission of CWD to red deer (Cervus elaphus elaphus): early detection and late stage distribution of protease-resistant protein


http://chronic-wasting-disease.blogspot.com/2009/09/experimental-oral-transmission-of.html




Thursday, September 24, 2009 Validation of Use of Rectoanal Mucosa-Associated Lymphoid Tissue for Immunohistochemical Diagnosis of Chronic Wasting Disease in White-Tailed Deer


http://chronic-wasting-disease.blogspot.com/2009/09/validation-of-use-of-rectoanal-mucosa.html




Tuesday, August 04, 2009

Susceptibilities of Nonhuman Primates to Chronic Wasting Disease

snip...

From: TSS (216-119-163-189.ipset45.wt.net)

Subject: CWD aka MAD DEER/ELK TO HUMANS ???

Date: September 30, 2002 at 7:06 am PST

From: "Belay, Ermias"

To:

Cc: "Race, Richard (NIH)" ; ; "Belay,

Ermias"

Sent: Monday, September 30, 2002 9:22 AM

Subject: RE: TO CDC AND NIH - PUB MED- 3 MORE DEATHS - CWD - YOUNG HUNTERS

Dear Sir/Madam,

In the Archives of Neurology you quoted (the abstract of which was attached to your email), we did not say CWD in humans will present like variant CJD.

That assumption would be wrong. I encourage you to read the whole article and call me if you have questions or need more clarification (phone: 404-639-3091). Also, we do not claim that "no-one has ever been infected with prion disease from eating venison." Our conclusion stating that we found no strong evidence of CWD transmission to humans in the article you quoted or in any other forum is limited to the patients we investigated.

Ermias Belay, M.D.

Centers for Disease Control and Prevention

-----Original Message-----

From:

Sent: Sunday, September 29, 2002 10:15 AM

To: rr26k@nih.gov; rrace@niaid.nih.gov; ebb8@CDC.GOV

Subject: TO CDC AND NIH - PUB MED- 3 MORE DEATHS - CWD - YOUNG

HUNTERS

Sunday, November 10, 2002 6:26 PM ......snip........end..............TSS

snip...


http://chronic-wasting-disease.blogspot.com/2009/08/susceptibilities-of-nonhuman-primates.html




Thursday, December 10, 2009


Chronic Wasting Disease (CWD) Susceptibility of Several North American Rodents That Are Sympatric with Cervid CWD Epidemics



http://chronic-wasting-disease.blogspot.com/2009/12/chronic-wasting-disease-cwd.html





TSS

Labels: , , ,

Chronic Wasting Disease (CWD) Susceptibility of Several North American Rodents That Are Sympatric with Cervid CWD Epidemics

Journal of Virology, January 2010, p. 210-215, Vol. 84, No. 1 0022-538X/10/$08.00+0 doi:10.1128/JVI.00560-09 Copyright © 2010, American Society for Microbiology. All Rights Reserved.

Chronic Wasting Disease (CWD) Susceptibility of Several North American Rodents That Are Sympatric with Cervid CWD Epidemics

Dennis M. Heisey,1* Natalie A. Mickelsen,1 Jay R. Schneider,1 Christopher J. Johnson,1,2 Chad J. Johnson,1,3 Julia A. Langenberg,4 Philip N. Bochsler,5 Delwyn P. Keane,5 and Daniel J. Barr5 Prion Research Laboratory, USGS National Wildlife Health Center, Madison, Wisconsin,1 Montana Cooperative Fishery Research Unit, Montana State University, Bozeman, Montana,2 University of Wisconsin School of Veterinary Medicine, Department of Comparative Biosciences, Madison, Wisconsin,3 Wisconsin Department of Natural Resources, Madison, Wisconsin,4 Wisconsin Veterinary Diagnostic Lab, Madison, Wisconsin5

Received 18 March 2009/ Accepted 6 October 2009

Chronic wasting disease (CWD) is a highly contagious always fatal neurodegenerative disease that is currently known to naturally infect only species of the deer family, Cervidae. CWD epidemics are occurring in free-ranging cervids at several locations in North America, and other wildlife species are certainly being exposed to infectious material. To assess the potential for transmission, we intracerebrally inoculated four species of epidemic-sympatric rodents with CWD. Transmission was efficient in all species; the onset of disease was faster in the two vole species than the two Peromyscus spp. The results for inocula prepared from CWD-positive deer with or without CWD-resistant genotypes were similar. Survival times were substantially shortened upon second passage, demonstrating adaptation. Unlike all other known prion protein sequences for cricetid rodents that possess asparagine at position 170, our red-backed voles expressed serine and refute previous suggestions that a serine in this position substantially reduces susceptibility to CWD. Given the scavenging habits of these rodent species, the apparent persistence of CWD prions in the environment, and the inevitable exposure of these rodents to CWD prions, our intracerebral challenge results indicate that further investigation of the possibility of natural transmission is warranted.

-------------------------------------------------------------------------------- * Corresponding author. Mailing address: USGS National Wildlife Health Center, 6006 Schroeder Road, Madison, WI 53711. Phone: (608) 270-2478. Fax: (608) 270-2415. E-mail: dheisey@usgs.gov

Published ahead of print on 14 October 2009.

-------------------------------------------------------------------------------- Journal of Virology, January 2010, p. 210-215, Vol. 84, No. 1 0022-538X/10/$08.00+0 doi:10.1128/JVI.00560-09 Copyright © 2010, American Society for Microbiology. All Rights Reserved.



http://jvi.asm.org/cgi/content/abstract/84/1/210?maxtoshow=&HITS=10&hits=10&RESULTFORMAT=&fulltext=cwd&searchid=1&FIRSTINDEX=0&volume=84&issue=1&resourcetype=HWCIT





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.



http://chronic-wasting-disease.blogspot.com/2009/08/third-international-cwd-symposium-july.html




Monday, July 13, 2009

Deer Carcass Decomposition and Potential Scavenger Exposure to Chronic Wasting Disease

http://chronic-wasting-disease.blogspot.com/2009/07/deer-carcass-decomposition-and.html




Thursday, September 10, 2009

Experimental oral transmission of CWD to red deer (Cervus elaphus elaphus): early detection and late stage distribution of protease-resistant protein


http://chronic-wasting-disease.blogspot.com/2009/09/experimental-oral-transmission-of.html



CWD, GAME FARMS, BAITING, AND POLITICS

http://chronic-wasting-disease.blogspot.com/2009/01/cwd-game-farms-baiting-and-politics.html




NOT only muscle, but now fat of CWD infected deer holds infectivity of the TSE (prion) agent. ...TSS


Monday, July 06, 2009

Prion infectivity in fat of deer with Chronic Wasting Disease

http://chronic-wasting-disease.blogspot.com/2009/07/prion-infectivity-in-fat-of-deer-with.html




Friday, February 20, 2009

Both Sides of the Fence: A Strategic Review of Chronic Wasting Disease

http://chronic-wasting-disease.blogspot.com/2009/02/both-sides-of-fence-strategic-review-of.html




Saturday, September 06, 2008

Chronic wasting disease in a Wisconsin white-tailed deer farm 79% INFECTION RATE

Contents: September 1 2008, Volume 20, Issue 5

snip...see full text ;


http://chronic-wasting-disease.blogspot.com/2008/11/commentary-crimes-hurt-essence-of.html





Saturday, January 24, 2009

Research Project: Detection of TSE Agents in Livestock, Wildlife, Agricultural Products, and the Environment Location: 2008 Annual Report


http://bse-atypical.blogspot.com/2009/01/research-project-detection-of-tse.html




Wednesday, January 07, 2009

CWD to tighten taxidermy rules Hunters need to understand regulations

http://chronic-wasting-disease.blogspot.com/2009/01/cwd-to-tighten-taxidermy-rules-hunters.html




Thursday, December 25, 2008 Lions and Prions and Deer Demise


http://chronic-wasting-disease.blogspot.com/2008/12/lions-and-prions-and-deer-demise.html



Tuesday, August 04, 2009

Susceptibilities of Nonhuman Primates to Chronic Wasting Disease

snip...

From: TSS (216-119-163-189.ipset45.wt.net)

Subject: CWD aka MAD DEER/ELK TO HUMANS ???

Date: September 30, 2002 at 7:06 am PST

From: "Belay, Ermias"

To:

Cc: "Race, Richard (NIH)" ; ; "Belay,

Ermias"

Sent: Monday, September 30, 2002 9:22 AM

Subject: RE: TO CDC AND NIH - PUB MED- 3 MORE DEATHS - CWD - YOUNG HUNTERS

Dear Sir/Madam,

In the Archives of Neurology you quoted (the abstract of which was attached to your email), we did not say CWD in humans will present like variant CJD.

That assumption would be wrong. I encourage you to read the whole article and call me if you have questions or need more clarification (phone: 404-639-3091). Also, we do not claim that "no-one has ever been infected with prion disease from eating venison." Our conclusion stating that we found no strong evidence of CWD transmission to humans in the article you quoted or in any other forum is limited to the patients we investigated.

Ermias Belay, M.D.

Centers for Disease Control and Prevention

-----Original Message-----

From:

Sent: Sunday, September 29, 2002 10:15 AM

To: rr26k@nih.gov; rrace@niaid.nih.gov; ebb8@CDC.GOV

Subject: TO CDC AND NIH - PUB MED- 3 MORE DEATHS - CWD - YOUNG

HUNTERS

Sunday, November 10, 2002 6:26 PM ......snip........end..............TSS

snip...

http://chronic-wasting-disease.blogspot.com/2009/08/susceptibilities-of-nonhuman-primates.html





http://chronic-wasting-disease.blogspot.com/





TSS

Labels: , , , ,

Sunday, December 06, 2009

Detection of Sub-Clinical CWD Infection in Conventional Test-Negative Deer Long after Oral Exposure to Urine and Feces from CWD+ Deer

Detection of Sub-Clinical CWD Infection in Conventional Test-Negative Deer Long after Oral Exposure to Urine and Feces from CWD+ Deer



Nicholas J. Haley1, Candace K. Mathiason1, Mark D. Zabel1, Glenn C. Telling2, Edward A. Hoover1*

1 Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, United States of America, 2 Department of Molecular Biology and Genetics, University of Kentucky, Lexington, Kentucky, United States of America

Abstract Top Background Chronic wasting disease (CWD) of cervids is a prion disease distinguished by high levels of transmissibility, wherein bodily fluids and excretions are thought to play an important role. Using cervid bioassay and established CWD detection methods, we have previously identified infectious prions in saliva and blood but not urine or feces of CWD+ donors. More recently, we identified very low concentrations of CWD prions in urine of deer by cervid PrP transgenic (Tg[CerPrP]) mouse bioassay and serial protein misfolding cyclic amplification (sPMCA). This finding led us to examine further our initial cervid bioassay experiments using sPMCA.

Objectives We sought to investigate whether conventional test-negative deer, previously exposed orally to urine and feces from CWD+ sources, may be harboring low level CWD infection not evident in the 19 month observation period. We further attempted to determine the peripheral PrPCWD distribution in these animals.

Methods Various neural and lymphoid tissues from conventional test-negative deer were reanalyzed for CWD prions by sPMCA and cervid transgenic mouse bioassay in parallel with appropriate tissue-matched positive and negative controls.

Results PrPCWD was detected in the tissues of orally exposed deer by both sPMCA and Tg[CerPrP] mouse bioassay; each assay revealed very low levels of CWD prions previously undetectable by western blot, ELISA, or IHC. Serial PMCA analysis of individual tissues identified that obex alone was positive in 4 of 5 urine/feces exposed deer. PrPCWD was amplified from both lymphoid and neural tissues of positive control deer but not from identical tissues of negative control deer.

Discussion Detection of subclinical infection in deer orally exposed to urine and feces (1) suggests that a prolonged subclinical state can exist, necessitating observation periods in excess of two years to detect CWD infection, and (2) illustrates the sensitive and specific application of sPMCA in the diagnosis of low-level prion infection. Based on these results, it is possible that low doses of prions, e.g. following oral exposure to urine and saliva of CWD-infected deer, bypass significant amplification in the LRS, perhaps utilizing a neural conduit between the alimentary tract and CNS, as has been demonstrated in some other prion diseases.

Citation: Haley NJ, Mathiason CK, Zabel MD, Telling GC, Hoover EA (2009) Detection of Sub-Clinical CWD Infection in Conventional Test-Negative Deer Long after Oral Exposure to Urine and Feces from CWD+ Deer. PLoS ONE 4(11): e7990. doi:10.1371/journal.pone.0007990

Editor: Jiyan Ma, Ohio State University, United States of America

Received: September 29, 2009; Accepted: October 29, 2009; Published: November 24, 2009

Copyright: © 2009 Haley et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Funding: This work was supported by NIH/NCRR Ruth L. Kirschstein Institutional T32 R07072-03 and NIH/NIAID NO1-AI-25491-02 (EAH, GCT). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Competing interests: The authors have declared that no competing interests exist.

* E-mail: Edward.Hoover@colostate.edu



SNIP...


In summary, we provide evidence for the presence of infectious prions in the brains of conventional prion-assay-negative deer orally exposed 19 months earlier to urine and feces from CWD-infected donor deer. This apparent low level of prion infection was amplified by sPMCA, confirmed by Tg[CerPrP] mouse bioassay, and detected only in the obex region of the brain. These results demonstrate the potential for CWD prion transmission via urine and/or feces, and highlight the application of more sensitive assays such as sPMCA in identification of CWD infection, pathogenesis, and prevalence.




http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0007990




Tuesday, June 16, 2009

Infectious Prions in Pre-Clinical Deer and Transmission of Chronic Wasting Disease Solely by Environmental Exposure


http://chronic-wasting-disease.blogspot.com/2009/06/infectious-prions-in-pre-clinical-deer.html



Molecular Model of Prion Transmission to Humans

Michael Jones, Darren Wight, Rona Barron, Martin Jeffrey, Jean Manson, Christopher Prowse, James W. Ironside, and Mark W. Head

To assess interspecies barriers to transmission of transmissible spongiform encephalopathies (TSEs), we investigated the ability of disease-associated prion proteins (PrPd) to initiate conversion of the human normal cellular form of prion protein of the 3 major PRNP polymorphic variants in vitro. Protein misfolding cyclic amplification showed that conformation of PrPd partly determines host susceptibility.

snip...

Conclusions

Our results are best appreciated in terms of the molecular interaction between seed PrPd and substrate PrPC, specifi cally the species-specific amino acid sequence and PRNP polymorphic status of PrPC and PrPd and the PrPd conformers involved (Table). Regardless of the seed PrP amino acid sequence, the PrPd conformers associated with bovine BSE, ovine BSE, and human vCJD were amplified in the humanized mouse substrate and displayed similar PRNP-129 genotype preferences (PRNP-129MM >PRNP- 129MV >PRNP-129VV). In contrast, the PrPd conformer associated with the ovine scrapie strain, although sharing the same PrP amino acid sequence as the PrPd in ovine BSE, could not be amplified in any of the PRNP humanized mouse substrates but could be amplifi ed in a sheep brain substrate. These observations are consistent with conformation of a TSE agent's PrPd (rather than solely its amino acid sequence) having a role in determining the susceptibility of a host's PrPC to conversion. They similarly suggest that these molecular factors could in turn have a powerful influence on disease susceptibility and incubation time.

To date, all clinical cases of vCJD have occurred in persons with the PRNP-129MM genotype, as might be predicted from the effi ciency of amplification of BSE-related PrPd shown here. Extrapolating from these results, one would predict that the next genotypic group most likely to show susceptibility to the BSE agent would be heterozygous (MV) at codon 129 of the PRNP gene, as previously suggested from the corresponding in vivo transmission studies (14).

In the wake of BSE epidemics in the United Kingdom and elsewhere, enhanced surveillance has identified apparently new TSEs (15), raising concerns regarding animal and human health. PMCA with suitable substrate sources could provide a rapid way to estimate the molecular component of transmission barriers for particular TSE agents between species, including humans. These estimates could thus indicate whether, like classical scrapie, the agents rep- resent little risk for human health or whether, like classical BSE, they represent cause for concern.

http://www.cdc.gov/eid/content/15/12/pdfs/2013.pdf




see more here ;



Saturday, December 05, 2009

Molecular Model of Prion Transmission to Humans


http://creutzfeldt-jakob-disease.blogspot.com/2009/12/molecular-model-of-prion-transmission.html




TSS

Labels: , , , , ,