Well I've read every post on here and I have to side with the non-use of any urine based scent. Whether or not the cause of CWD is known anything a sensible hunter can do to prevent the disease from spreading is well worth it. If this means not using a urine based scent so be it.
Is your ego so big or your hunting skills so bad (or your wallet so greedy) that you can't go without the ability to lure a buck into shooting range?
As for the disease itself, I will be first to admit I know very little about it except that it is bad for a deer herd. And for my own hunting future and that of my grandchildren if not using urine based scents is all I have to do to ensure it then that is what I will do.