Australian beef is the cleanest and purest, by far.
Australian venison should be fine, too.
Not so sure about Australian lamb, though....
Actually this is a potential matter of concern. Too little is known about prion diseases and the potential effects of them. Sheep have had a prion disease for centuries (scrapie) which has never been shown to manifest in any disease in humans
that we yet know of. It wouldn't surprise me in the least if we find a link with scrapie and, say, multiple sclerosis, or something.
Prion disease links are tenous to say the best, though. The evidence for BSE causing vCJD in humans is still mainly circumstantial, and the mode of transmission (if any) is still unclear. Many theories have been suggested, none really proven by Koch's postulates yet.
My suggestions? Life is a bit of a lottery. If you listen to all the doomsayers, you wan't eat or drink anything!

So, as long as you avoid obviously sick and diseased animals, and make sure you cook meat well, the risk should be low. Avoid spinal tissue and brains in any animals, IMO, as these would be highest for prions if they are in any way harmful.
Oh, and if you eat brains and drink lots of alcohol, that is probably bad too, as alcohol may increase the infectivity of prions, according to some theories. Sorry, Lemon. Sounds like you are in trouble, then.
Cheers
Mick