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Saturday, February 20, 2016

Seeded amplification of chronic wasting disease prions in nasal brushings and recto-anal mucosa associated lymphoid tissues from elk by real time quaking-induced conversion

Seeded amplification of chronic wasting disease prions in nasal brushings and recto-anal mucosa associated lymphoid tissues from elk by real time quaking-induced conversion
 
Nicholas J. Haley#,a, Chris Siepkera, Laura L. Hoon-Hanksb, Gordon Mitchellc, W. David Walterd, Matteo Mancae, Ryan J. Monellof, Jenny G. Powersf, Margaret A. Wildf, Edward A. Hooverb, Byron Caugheye and Jürgen A. Richta + Author Affiliations
 
Department of Diagnostic Medicine and Pathobiology, College of Veterinary Medicine, Kansas State University (KSU), Manhattan, KS, USAa Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, USAb Canadian Food Inspection Agency, National and OIE Reference Laboratory for Scrapie and CWD, Ottawa Laboratory Fallowfield, Ottawa, ON, Canadac U.S. Geological Survey, Pennsylvania Cooperative Fish and Wildlife Research Unit, The Pennsylvania State University, University Park, PA, USAd TSE/Prion Biochemistry Section, Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories (RML), National Institute of Allergy and Infectious Diseases, Hamilton, MT, USAe National Park Service, Biological Resources Division, 1201 Oak Ridge Drive, Suite 200, Fort Collins, Colorado 80525, USAf
 
ABSTRACT
 
Chronic wasting disease (CWD), a transmissible spongiform encephalopathy of cervids, was first documented nearly fifty years ago in Colorado and Wyoming, and has since been detected across North America and to the Republic of Korea. The expansion of this disease makes the development of sensitive diagnostic assays and antemortem sampling techniques crucial for the mitigation of spread; this is especially true in cases of relocation/reintroduction, or prevalence studies in large or protected herds where depopulation may be contraindicated. This study sought to evaluate the sensitivity of the real-time quaking-induced conversion (RT-QuIC) assay in recto-anal mucosa associated lymphoid tissue (RAMALT) biopsies and nasal brushings collected antemortem. These findings were compared to results from ante- and postmortem samples evaluated using immunohistochemistry (IHC). RAMALT samples were collected from populations of farmed and free-ranging Rocky Mountain elk (Cervus elaphus nelsoni, n=323), with nasal brushes collected from a subpopulation of these animals (n=205). We hypothesized the sensitivity of RT-QuIC would be comparable to IHC in RAMALT, and would correspond to IHC of postmortem tissues. We found RAMALT sensitivity (77.3%) to be highly correlative between RT-QuIC and IHC. Sensitivity was lower when testing nasal brushings (34%), though both RAMALT and nasal brush sensitivities were dependent on both PRNP genotype and disease progression determined by obex score. These data suggest that RT-QuIC, like IHC, is a relatively sensitive assay for detection of CWD prions in RAMALT biopsies, and with further investigation has potential for large scale and rapid automated testing for CWD in antemortem samples.
 
FOOTNOTES
 
↵#Corresponding author (e-mail: nicholas.j.haley@gmail.com) Copyright © 2016, American Society for Microbiology. All Rights Reserved. http://jcm.asm.org/content/early/2016/02/11/JCM.02700-15.abstract
 
Sunday, February 14, 2016
 
Antemortem detection of chronic wasting disease prions in nasal brush collections and rectal biopsies from white-tailed deer by real time quaking-induced conversion
 
 
Real and perceived issues involving animal proteins C. R. Hamilton May 3, 2002, a review of USDA MAD COW DISEASE BSE FEED
 
FIRST, please see the drastic decrease of mad cow disease in the UK after the mad cow feed ban went into force ;
 
SUMMARY OF PASSIVE SURVEILLANCE REPORTS IN GREAT BRITAIN
 
PASSIVE SURVEILLANCE
 
SUSPECTS RESTRICTIONS LIFTED DUE TO ALTERNATIVE SLAUGHTER NOT YET SUSPECTS KNOWN TO HAVE BEEN SLAUGHTERED SUSPECTS WITH OUTCOME SLAUGHTERED SUSPECTS IN WHICH BSE NOT SLAUGHTERED SUSPECTS IN WHICH BSE PRIVATE SUBMISSIONS IN WHICH
 
YEAR RESTRICTED DIAGNOSIS NOTIFIED SLAUGHTERED PENDING CONFIRMED CONFIRMED BSE CONFIRMED
 
Pre 18.07.88 1142 1 0 980 0 414 727 0
 
1988 2512 140 0 2372 0 192 2180 4
 
1989 8443 386 0 8057 0 924 7133 4
 
1990 17323 682 0 16641 0 2460 14181 0
 
1991 30003 982 0 29021 0 3995 25026 6
 
1992 44844 1690 0 43154 0 6474 36680 2
 
1993 42931 1847 0 41084 0 6714 34370 0
 
1994 30259 1551 0 28708 0 4765 23943 2
 
1995 17945 789 0 17156 0 2855 14301 1
 
1996 10697 547 0 10150 0 2137 8013 3
 
1997 5604 302 0 5302 0 992 4310 3
 
1998 4291 260 0 4031 0 852 3179 1
 
1999 2984 146 0 2838 0 582 2256 2
 
2000 1870 117 0 1753 0 442 1311 0
 
2001 1218 66 0 1152 0 371 781 0
 
2002 877 68 0 809 0 364 445 0
 
2003 456 43 0 413 0 240 173 0
 
2004 351 41 0 310 0 228 82 0
 
2005 186 30 0 156 0 117 39 0
 
2006 144 26 0 118 0 103 15 0
 
2007 69 11 0 58 0 51 7 0
 
2008 39 7 0 32 0 30 2 0
 
2009 22 7 0 15 0 14 1 0
 
2010 19 7 0 12 0 12 0 0
 
2011 11 2 0 9 0 9 0 0
 
2012 5 2 0 3 0 3 0 0
 
2013 2 0 0 2 0 2 0 0
 
2014 2 0 0 2 0 2 0 0
 
2015 0 0 0 0 0 0 0 0
 
2016 0 0 0 0 0 0 0 0
 
Total 223107 9749 0 213358 0 34930 178428 28
 
Data valid to 31 January 2016
 
 
SECOND, what has MAFF...now DEFRA, what have they said about the mad cow feed ban in the USA in 2012?
 
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...
 
In the USA, under the Food and Drug Administration’s BSE Feed Regulation (21 CFR 589.2000) most material (exceptions include milk, tallow, and gelatin) from deer and elk is prohibited for use in feed for ruminant animals. With regards to feed for non-ruminant animals, under FDA law, CWD positive deer may not be used for any animal feed or feed ingredients. For elk and deer considered at high risk for CWD, the FDA recommends that these animals do not enter the animal feed system. However, this recommendation is guidance and not a requirement by law.
 
Animals considered at high risk for CWD include:
 
1) animals from areas declared to be endemic for CWD and/or to be CWD eradication zones and
 
2) deer and elk that at some time during the 60-month period prior to slaughter were in a captive herd that contained a CWD-positive animal.
 
Therefore, in the USA, materials from cervids other than CWD positive animals may be used in animal feed and feed ingredients for non-ruminants.
 
The amount of animal PAP that is of deer and/or elk origin imported from the USA to GB can not be determined, however, as it is not specified in TRACES. It may constitute a small percentage of the 8412 kilos of non-fish origin processed animal proteins that were imported from US into GB in 2011.
 
Overall, therefore, it is considered there is a __greater than negligible risk___ that (nonruminant) animal feed and pet food containing deer and/or elk protein is imported into GB.
 
There is uncertainty associated with this estimate given the lack of data on the amount of deer and/or elk protein possibly being imported in these products.
 
snip...
 
36% in 2007 (Almberg et al., 2011). In such areas, population declines of deer of up to 30 to 50% have been observed (Almberg et al., 2011). In areas of Colorado, the prevalence can be as high as 30% (EFSA, 2011). The clinical signs of CWD in affected adults are weight loss and behavioural changes that can span weeks or months (Williams, 2005). In addition, signs might include excessive salivation, behavioural alterations including a fixed stare and changes in interaction with other animals in the herd, and an altered stance (Williams, 2005). These signs are indistinguishable from cervids experimentally infected with bovine spongiform encephalopathy (BSE). Given this, if CWD was to be introduced into countries with BSE such as GB, for example, infected deer populations would need to be tested to differentiate if they were infected with CWD or BSE to minimise the risk of BSE entering the human food-chain via affected venison.
 
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...
 
 
THIRD, THE USDA FDA TRIPLE MAD COW DISEASE FIREWALL, WAS NOTHING MORE THAN INK ON PAPER !
 
now, let’s just for a moment put away the corporate junk science, and let’s look at recent updated BSE, CWD, Scrapie, TSE Prion sound science, could not hurt...
 
Saturday, January 31, 2015
 
European red deer (Cervus elaphus elaphus) are susceptible to Bovine Spongiform Encephalopathy BSE by Oral Alimentary route
 
 
I strenuously once again urge the FDA and its industry constituents, to make it MANDATORY that all ruminant feed be banned to all ruminants, and this should include all cervids as soon as possible for the following reasons...
 
======
 
In the USA, under the Food and Drug Administrations BSE Feed Regulation (21 CFR 589.2000) most material (exceptions include milk, tallow, and gelatin) from deer and elk is prohibited for use in feed for ruminant animals. With regards to feed for non-ruminant animals, under FDA law, CWD positive deer may not be used for any animal feed or feed ingredients. For elk and deer considered at high risk for CWD, the FDA recommends that these animals do not enter the animal feed system.
 
***However, this recommendation is guidance and not a requirement by law.
 
======
 
31 Jan 2015 at 20:14 GMT
 
*** Ruminant feed ban for cervids in the United States? ***
 
31 Jan 2015 at 20:14 GMT
 
see Singeltary comment ;
 
 
Oral transmission and early lymphoid tropism of chronic wasting disease PrPres in mule deer fawns (Odocoileus hemionus )
 
These results indicate that CWD PrP res can be detected in lymphoid tissues draining the alimentary tract within a few weeks after oral exposure to infectious prions and may reflect the initial pathway of CWD infection in deer. The rapid infection of deer fawns following exposure by the most plausible natural route is consistent with the efficient horizontal transmission of CWD in nature and enables accelerated studies of transmission and pathogenesis in the native species.
 
snip...
 
These results indicate that mule deer fawns develop detectable PrP res after oral exposure to an inoculum containing CWD prions. In the earliest post-exposure period, CWD PrPres was traced to the lymphoid tissues draining the oral and intestinal mucosa (i.e. the retropharyngeal lymph nodes, tonsil, ileal Peyer's patches and ileocaecal lymph nodes), which probably received the highest initial exposure to the inoculum. Hadlow et al. (1982) demonstrated scrapie agent in the tonsil, retropharyngeal and mesenteric lymph nodes, ileum and spleen in a 10-month-old naturally infected lamb by mouse bioassay. Eight of nine sheep had infectivity in the retropharyngeal lymph node. He concluded that the tissue distribution suggested primary infection via the gastrointestinal tract. The tissue distribution of PrPres in the early stages of infection in the fawns is strikingly similar to that seen in naturally infected sheep with scrapie. These findings support oral exposure as a natural route of CWD infection in deer and support oral inoculation as a reasonable exposure route for experimental studies of CWD.
 
snip...
 
 
Title: Experimental oral transmission of chronic wasting disease (CWD) to red deer (Cervus elaphus elaphus): early detection and late stage distribution of protease-resistant protein (PrP-res)
 
In this study, red deer (Cervus elaphus elaphus) were exposed to the prion agent by oral administration of brain homogenates from infected Rocky Mountain elk. Antemortem testing was performed at 7 months post infection and the deer were euthanized when clinical disease was observed at approximately 18 months after infection. The abnormal prion protein was assayed by immunohistochemistry, enzyme linked immunosorbent assay and western blot. Abnormal prion protein was found in the spinal cord, brainstem, cerebellum, midbrain, thalamus, and cerebrum in all 4 infected red deer. Most of the lymph nodes throughout the body were positive for abnormal prion proteins. Abnromal prion protein was observed in some additional peripheral tissues in some but not all of the deer. In particular, most areas of the gastrointestinal tract were positive for abnormal prions, although the salivary glands were rarely positive. This study demonstrates the potential for oral transmission of chronic wasting disease to red deer and confirms the usefulness of the current testing methods for post mortem diagnosis of the disease in this species.
 
 
*** Singeltary reply ; Molecular, Biochemical and Genetic Characteristics of BSE in Canada Singeltary reply ;
 
 
SNIP...SEE FULL TEXT AND MORE HERE ;
 
Tuesday, February 16, 2016
 
Real and perceived issues involving animal proteins C. R. Hamilton May 3, 2002, a review of USDA MAD COW DISEASE BSE FEED AND CERVIDS
 
 
 Terry S. Singeltary Sr.
 

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