Wednesday, November 28, 2012

Prions in the wild, CWD-Chronic Wasting Disease, and Prion Diseases in Animals and Humans - Updated

[This is going to be a open entry also that because of its severity and potential  will need to be updated frequently. I also need to become more familiar with the technical aspects of it. After the sources there is a dated narrative section.]

Brazil’s First Case of Mad Cow Disease Hidden for Months

December 7, 2012 (ENS) – Brazil has notified international animal health regulators of its first case of bovine spongiform encephalopathy, BSE, commonly called mad cow disease. The cow died two years ago, but the test confirming the deadly brain disease was not done until 18 months later, and the results not made public until Thursday.

This time lag allowed Brazil to export roughly 67 million pounds of beef to the United States since the suspect Brazilian cow was identified.
( )

UPDATE 2-Brazil government denies reports of 2010 mad cow case ( )

From July:

Naples woman suffering from Mad Cow Disease ( )

CWD detected in Texas -

Two Cases of Chronic Wasting Disease Found in Western Texas - July 12, 2012

Texas Parks and Wildlife began monitoring the area's deer after CWD was detected across the border in New Mexico. Samples were taken from 31 deer in the area, but both infected deer were taken from a small area of the Hueco Mountains in El Paso County. So what's next? Continued monitoring and containment, hopefully.

Statement by USDA Chief Veterinary Officer John Clifford Regarding a Detection of Bovine Spongiform Encephalopathy (BSE) in the United States - April 24, 2012

"As part of our targeted surveillance system, the U.S. Department of Agriculture's (USDA) Animal and Plant Health Inspection Service (APHIS) has confirmed the nation's fourth case of bovine spongiform encephalopathy (BSE) in a dairy cow from central California. The carcass of the animal is being held under State authority at a rendering facility in California and will be destroyed. It was never presented for slaughter for human consumption, so at no time presented a risk to the food supply or human health. Additionally, milk does not transmit BSE. 

I will note here that milk has not been found to be involved or is not suspected in the transmission of BSE.  I dont know why they said it like that.

Original post:

For now Ill lump all mammalian prion diseases together until there is reason to differentiate them.

Prions are incorrectly folded proteins that "replicate" in organisms by causing other proteins to become mis-folded.

In prion disease, infectious prions or proteianceous infectious particles enter the organism, replicate exponentially by contact with the correct versions of the protein (usually after being ingested) and form Amyloids ( insoluble fibrous protein aggregates).


Mammalian cells generate cellular prion protein (PrP), after being infected with a prion disease.

An additionally alarming aspect of prions is the difficulty by which they are destroyed. They are resistant to heat and radiation treatments and seem to survive in the environment for years. As they can be excreted by infected organisms in urine feces, saliva and bodily fluids they have become a major, if not downplayed concern in public health.

 As they can be derived from unused portions and substandard cuts of meat pet feeds are particularly prone to contamination. With fertilizers being derived form sewage and animal wastes, plant products are also susceptible to prion contamination.

In Britain one of the largest countries to be affected by a prion disease vCJD entered the food chain it is thought by the extensive use of rendered meant products and the use of animal products in animal feeds. As normal processing didn't destroy the Prions it was thought contamination did not merely occur in meat products but spread through things like cake mixes and puddings.

Even though thousands of Britains were suspected of being exposed, actual cases of vCJD peaked and have tapered off to a few a year. A variety of reasons for this have been proposed.

In contrast to lowed livestock infections and a drop ion human cases prion diseases in the wild seem to be spreading. While no direct links to exposure to  infected wildlife exists for human infection, it remains a strong possibility and some curious narratives do exist . 

Chronic Wasting Disease Among Free-Ranging Cervids by County, United States, March 2011

Map of Chronic Wasting Disease Among Free-Ranging Cervids
CDC - Chronic wasting disease (CWD) is a prion disease that affects North American cervids (hoofed ruminant mammals, with males characteristically having antlers). The known natural hosts of CWD are mule deer, white-tailed deer, elk, and moose. CWD was first identified as a fatal wasting syndrome in captive mule deer in Colorado in the late 1960s and in the wild in 1981. It was recognized as a spongiform encephalopathy in 1978. To date, no strong evidence of CWD transmission to humans has been reported.

Since first bing discovered CWD is on the move and has spread to several states and Canada the latest place its showed up is Missouri.


Britain - Thousands may be harbouring vCJD 2004

Britain- vCJD carrier risk 'overestimated' 2009

Fatal Degenerative Neurologic Illnesses in Men Who Participated in Wild Game Feasts --- Wisconsin, 2002

Creutzfeldt-Jakob Disease in Unusually Young Patients Who Consumed Venison

Chronic Wasting Disease and Potential Transmission to Humans

Chronic Wasting Disease 

Even vegetarians may not be safe from 'mad cow' prions 

Prion Protein in Milk

Prion protein in sheep urine

Prions can survive sewage treatment, UW-Madison study says

BSE (Bovine Spongiform Encephalopathy, or Mad Cow Disease)

CDC BSE (Bovine Spongiform Encephalopathy, or Mad Cow Disease) References and Resources

Narrative / press updates:

Brain-Wasting Prions Amass Before Dealing Deathblow-February 25, 2011

Experimental Oral Transmission of Atypical Scrapie to Sheep-5May 2011

Potential Human Exposure to Prion Diseases Assessed-May 23, 2011

Scientists Identify Most Lethal Known Species of Prion Protein-February 09, 2012

Fatal disease confirmed
in sheep -herd quarantine unlikely - Feb. 23rd, 2012

Ozone-treated water can eradicate prions in the brain of infected animals- Mar 01, 2012

CWD now is in Missouri - Mar 01, 2012

Statement by USDA Chief Veterinary Officer John Clifford Regarding a Detection of Bovine Spongiform Encephalopathy (BSE) in the United States - April 24, 2012 

 Two Cases of Chronic Wasting Disease Found in Western Texas - July 12, 2012

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