1 reply [Last post]
Location: Colorado
Joined: 11/09/2005
Posts: 164
CWD in the meat

Heard on the radio this morning that researchers have found the prion that is related to CWD in the meat of a deer. Previously it had only been found in the lymph nodes, spinal/brain tissue, and certain organs, but not in the meat. This is a cause for concern because if ingesting the prions is the way CWD is communicated--as researchers suspect, but have not yet proven--then the fact that it is in the meat could indicate that you can contract the disease (or the human equivalent--CJD) by eating venison.

Here's a link to a NY Times article on the subject...

bitmasher's picture
Location: Colorado
Joined: 02/27/2002
Posts: 2974
CWD in the meat

I'm repeating what I posted in another thread, since its relevant to this discussion...

Now about this most recent Science article regarding a finding of prions in muscle tissue. Is anybody really suprised by this?

I read the "materials and methods" section of the online article that Flounder pointed to and the authors state "the utmost care was taken to avoid inclusion of obvious nervous tissue when muscle biopsies were prepared".

In other words we took a chunk of meat that as best we could tell contained no nervous system tissue. Most likely though this tissue still contained micro amounts of neurons. Personally I would not be suprised if an CWD carrier has prions expressed in all neurons no matter how remote. The issue is whether individual muscle carry and replicate prions.

Now the rest of the experiment was to prepare serums from the muscle tissue samples and then inject them into rats. Further they injected them into the rats brains. Wait awhile and it turns out the rats come down with CWD, which was varied by visual examination and by electrophresis of samples of the infected rats. The same thing has been demonstrated with bovines with serums prepared from cwd infected deer nervous tissue when injected directly into their brain. Other tests have shown that bovines can be fed (eaten with regular food) CWD laced food and they do not contract CWD. This is a huge and important distinction that is not addressed in laymen terms but the science is already there.

What this article means to me is that prions can replicate in a host from trace amounts. What this article does not mean to me is that even if I were to eat, CWD laced meat that I would contract it. Personally I would not be suprised if the prions (of CWD or CJD flavor, if they are in fact different) were injected into human brains they would become infected.

As a hunter what does this mean to me? Unfortunately not much. If they had shown that rats (or any mammal) fed infected meat became sick, I would be very concerned.

Now lets talk for a moment about variance in a human population. Do any of you know how hard it is to create a perfect drug? Perfect meaning one that does exactly the same effect in everyone and exactly no different side effects in everyone. It is impossible. Why? Because frankly everyone is different and even tiny difference can find expression when applied to huge populations. In other words even if a drug shows death side effects in only 0.0001% (that's 99.9999% perfect) of a population, if the drug is given to 1,000,000 people exactly 1 person is likely to die because of taking the drug.

I suspect that the CWD/CJD issue is the same sort of analysis (very much an educated GUESS on my part). 99.9999% (or somewhere in that neighborhood) of us can consume prion infected meat but not contract the disease. (There is a whole other discussion of why I believe this but I'll refrain for now) Unfortunately do to natural variation and randomness some may still become infected. Does this mean CWD/CJD/Mad Cow is a huge worry? Not really. Certainly it does if your the infected person or their family, no doubt, but from a population wide analysis, more people will die in car accidents in the next hour....

Notice I said EAT, if we are injected with the prions like the rats in this experiment or the cows of past experiments that I alluded too, I think it very likely that a high percentage of us would contract CWD. Is that so amazing though? Not really...

I still think hunters should have their game analized in areas with cwd known in the herd and destory the game if it is found positive. Never hurts to be safe; however I think there is a disconnect between what science is showing and the practicality to a typical hunter.