- Hello, Jeff -
-
- So, what else is new. We have been talking about this
for eons. Jeff Rense and Patty Doyle knew then what the scientists have
just now proven. Maybe they weren't looking very hard before...
-
- How many people became infected eating deer meat during
all this time? Yet, I know that people will continue to eat deer and continue
to cast aside our warnings. Now they must cast aside scientific research,
too. And most they probably will.
-
- Infectious Prions In The Saliva And Blood
- Of Deer With Chronic Wasting Disease (Mad Cow)
-
- Candace K. Mathiason,1 Jenny G. Powers,3 Sallie J. Dahmes,4
David A. Osborn,5 Karl V. Miller,5
- Robert J. Warren,5 Gary L. Mason,1 Sheila A. Hays,1 Jeanette
Hayes-Klug,1 Davis M. Seelig,1
- Margaret A. Wild,3 Lisa L. Wolfe,6 Terry R. Spraker,1,2
Michael W. Miller,6 Christina J. Sigurdson,1
- Glenn C. Telling,7 Edward A. Hoover1*
-
- A critical concern in the transmission of prion diseases,
including chronic wasting disease (CWD) of cervids, is the potential presence
of prions in body fluids. To address this issue directly, we exposed cohorts
of CWD-nai¨ve deer to saliva, blood, or urine and feces from CWD-positive
deer. We found infectious prions capable of transmitting CWD in saliva
(by the oral route) and in blood (by transfusion). The results help to
explain the facile transmission of CWD among cervids and prompt caution
concerning contact with body fluids in prion infections.
-
- SNIP...
-
- Deer cohorts 1 (blood), 2 (saliva), and 3 (urine and
feces) were electively euthanized at 18 months pi to permit whole-body
examination for PrPCWD. The greatest scrutiny was directed toward those
tissues previously established to have highest frequency of PrPCWD deposition
in infected deer and generally regarded as the most sensitive indicators
of infection" medulla oblongata and other brainstem regions, tonsil,
and retropharyngeal lymph node. We found unequivocal evidence of PrPCWD
in brain and lymphoid tissue of all six tonsil biopsy positive deer in
cohorts 1 (blood) and 2 (saliva), whereas all deer in cohorts 3 and 5 were
negative for PrPCWD in all tissues (Table 2 and Figs. 1 and 2).
-
- The transmission of CWD by a single blood transfusion
from two symptomatic and one asymptomatic CWDþ donor is important
in at least three contexts: (i) It reinforces that no tissue from CWD-infected
cervids can be considered free of prion infectivity; (ii) it poses the
possibility of hematogenous spread of CWD, such as through insects; and
(iii) it provides a basis for seeking in vitro assays sufficiently sensitive
to demonstrate PrPCWD or alternate prion protein conformers in blood"one
of the grails of prion biology and epidemiology. The identification of
blood-borne prion transmission has been sought before with mixed results
(911). Bovine spongiform encephalopathy and scrapie have been transmitted
to naBve sheep through the transfer of 500 ml of blood or buffy coat white
blood cells from infected sheep (12, 13). In addition, limited but compelling
evidence argues for the transmission of variant Creutzfeldt-Jakob disease
(vCJD) through blood from asymptomatic donors (1416). Even in sporadic
CJD, PrPres has been found in periph- eral organs of some patients (17).
-
- The present work helps establish that prion diseases
can be transmitted through blood. The presence of infectious CWD prions
in saliva may explain the facile transmission of CWD. Cervid-to-cervid
interactions (SOM text), especially in high density and captive situations,
would be expected to facilitate salivary crosscontact (11, 18, 19). Salivary
dissemination of prions may not be limited to CWD. Proteaseresistant prion
protein has been demonstrated in the oral mucosa, taste buds, lingual epithelium,
vomeronasal organ, and olfactory mucosa of hamsters infected with transmissible
mink encephalopathy (19) and ferrets infected with CWD (20). Although no
instance of CWD transmission to humans has been detected, the present results
emphasize the prudence of using impervious gloves during contact with saliva
or blood of cervids that may be CWD-infected. Environmental contamination
by excreta from infected cervids has traditionally seemed the most plausible
explanation for the dissemination of CWD (21). However, we could not detect
PrPCWD in cohort 3 deer inoculated repeatedly with urine and feces from
CWDþ deer and examined up to 18 months pi (Table 2).
-
- There are several reasons to view this negative finding
cautiously, including small sample size, elective preclinical termination,
and potential variation in individual susceptibility that may be associated
with the 96 G/S polymorphism in the PRNP gene (7, 22). Although no genotype
of white-tailed deer is resistant to CWD infection, PRNP genotypes S/S
or G/S at codon 96 appear to have reduced susceptibility manifest by longer
survival (7). Both deer in cohort 3 (urine and feces) were subsequently
shown to be of the PRNP 96 G/S genotype. Thus, it is possible, although
we think unlikely, that these deer had a prolonged incubation period (918
months pi) before the amplification of PrPCWD became detectable in tissues.
Recent studies have shown that PrPres is poorly preserved after incubation
with intestinal or fecal content (23, 24). Further research using cervid
and surrogate cervid PrP transgenic mice (25) are indicated to continue
to address the presence of infectious CWD prions in excreta of CWDþ
deer and to provide a more substantial basis for reconsideration of the
assumption that excreta are the chief vehicle for CWDdissemination and
transmission.
-
- The results reported here provide a plausible basis for
the efficient transmission of CWD in nature. We demonstrate that blood
and saliva in particular are able to transmit CWD to naBve deer and produce
incubation periods consistent with those observed in naturally acquired
infections (3, 26). The time from exposure to first detection of PrPCWD
by tonsil biopsy was variable"as short as 3 months but as long as
18 months (likely underestimates due to sampling frequency). The results
also reinforce a cautious view of the exposure risk presented by body fluids,
excreta, and all tissues from CWDþ cervids. ...
-
- SNIP...END
-
- http://www.sciencemag.org/cgi/content/abstract/314/5796/133
-
- http://www.sciencemag.org/
-
- CWD AND ENVIRONMENTAL FACTORS i.e. saliva, fecal shedding
and fecal-oral transmission is likely
-
- http://p079.ezboard.com/fwolftracksproductionsfrm2.showMessage?topicID=592.topic
-
- THE SEVEN SCIENTIST REPORT ***
-
- http://www.fda.gov/ohrms/dockets/dockets/02n0273/02n-0273-EC244-Attach-1.pdf
-
- Subject: [Docket No. FSIS-2006-0011] FSIS Harvard Risk
Assessment of Bovine
- Spongiform Encephalopathy (BSE)
-
-
- http://www.fsis.usda.gov/OPPDE/Comments/2006-0011/2006-0011-1.pdf
-
-
- [Docket No. 03-025IFA] FSIS Prohibition of the Use of
Specified Risk
- Materials for Human Food and Requirement for the Disposition
of
- Non-Ambulatory Disabled Cattle
-
- 03-025IFA
- 03-025IFA-2
-
-
- From Terry S. Singeltary
-
- Patricia A. Doyle DVM, PhD
- Bus Admin, Tropical Agricultural Economics
- Univ of West Indies
-
- Please visit my "Emerging Diseases" message
board at:
- http://www.emergingdisease.org/phpbb/index.php
- Also my new website:
- http://drpdoyle.tripod.com/
- Zhan le Devlesa tai sastimasa
- Go with God and in Good Health
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