Eating Prions and Mad Cows

[science_spot]

 

Mad Cow Disease has a "real" name.  It's Bovine Spongiform Encephalopathy (BSE). 

This is one disease that falls under the header of Transmissible Spongiform Encephalopathy (TSE).  Other common TSE diseases are Chronic Wasting Disease (deer and elk), scrapie (sheep), as well as Creutzfeldt-Jakob Disease and Kuru in humans.

These diseases are thought to be caused solely by mis-folded proteins, called prions (however, there are other hypotheses).  The prions can be either inherited (DNA variations/mutations) or transmitted among animals.  BSE causes deterioration in the animal's physical and mental abilities, which will lead to death.  One mark of the disease is the inability of the affected animal to stand. 

What difference does it make?  First, cattle is a major component of our food supply, and second, TSE disease occurs in humans, and BSE can be transmitted to humans (varient-Creutzfeldt-Jakob Disease or vCJD).

In the 1980s a BSE epidemic in the UK lead to the purposeful destruction of hundreds of thousands of animals, in an attempt to stop the spread of the disease.  But infected meat had already made its way to the table, thus transmitting the prions (which causes vCJD disease in humans) to people in Britian.  By 2009, over 100 people had died and more are expected due to the relatively long incubation time between infetion and death.  It is known prions are not destroyed by the normal cooking process.

It was determined the transmission of the prions among cattle was likely due to the practice of feeding cattle with ground meal manufactured from "parts" leftover from the slaughter of animals for human consumption, as well as sick animals (cattle, sheep, chickens) not fit for human consumption.  An infected animal was used in the meal that was subsequntly used to feed thousands of animals destined for the food supply.

How do we prevent this from happening again?  The problem has been addressed from a few angles, thus minimizing the risk. 

First, bovine products are not imported from countries/regions with known cases of BSE, including the UK. 

Second, the USA has strict regulations regarding cattle feeds.  Some groups think the regulations regarding the feeds of other animals should be stricter because these animals (chickens, sheep, etc.) are often feed to cattle.  However, since there have only been a few reported cases of BSE in the USA, it seems additional regulation may not be necessary.  Adding stricter regulations on the food industry drives up food prices; we don't need higher food costs without adding a benefit of lower risk.

Third, research into BSE has been plentiful, specifically in terms of detection methods, transmissibility, and prion load of particular organs.  This research has resulted in the regulations set up by the FDA, USDA, andtracking by the CDC.  Luckily, the three most comonly used cattle "parts are blood, milk and muscle meat, which show no infectivity. 

Fourth, our food supply is not the only area the USA addressed concern. Animal products are often used in the manufacture of cosmetics and medicine/vaccines.  These risks are addressed in the paper now deemed the industry standard - "Notes for Guidance on Minimising the Risk of Transmitting Animal Spongiform Encephalopathy via human and Veternary Medicinal Products".  This is a free publication, and not difficult to read.

Have you read enough to swear off beef or milk?  Do you think the USA is doing enough to protect you from the risk of vCJD?

Politcal cartoon by R.J. Matson

 

 

Tonya

AKA sunmoonstars

The Science Spot

 

 

[warmcoffee]

Jun. 4, 2010 at 10:23 AM

Love the poster. Article very interesting!!!  BTW, I woke up this morning wanting a hamburger but did not, now i'm not so sure., yesterday we had roast beef smothered in onions, red, green and orange peppers and garlic with gravy + mashed potatoes and spinach. Right, prayer is essential, however, I think the gov. should not think it too expensive to have mandatory testing, afterall, their children are eating it too.  Thanks for the update, as I though this testing was done all of the time, not randomly.

[warmcoffee]

Jun. 4, 2010 at 10:24 AM

BTW, voted popular, as we all should be more aware.

[jen5309]

Jul. 23, 2010 at 11:48 PM

I believe that way more testing and research should be done.  Here goes. Get ready for my rant.! sCJD is not even reportable in most states( the disease from unknown origin).  Researchers aren't sure if there is or is not a link from anything we eat and the sporadic form of CJD.  My 39 year old husband died last november after being diagnosed with sCJD less than two months earlier.  I have been told this affects one person per million per year worldwide.  How do they really know this if there is no mandatory reporting? At one point in my husbands illness he was thought to have lyme disease.  The CDC called my home.  How stupid is that.  A disease that can make you miserable for a while and possibly have some life long effects is always reported to the CDC.  However, a disease that can take you from playing full court basketball to the grave in 6 months, a demon that leaves children fatherless, this disease is not reportable. How can research be furthered until it is made reportable in all states? And BTW I did donate his brain tissue in the name of research.