TSS,

What we have here is a difference in our understanding of terminological exactitude (unlike Coolhand Luke whose problem was failure to communicate). The term BASE, as I understand it, refers strictly to L-type BSE and does not encompass H-type BSE. This is the understanding of the terminology as presented in the transmission study in the January edition of the Journal of Virology. This is also the understanding of the terminology of all of the scientific papers you have cited so far.

Forgive me for being anal about precision in scientific terminology, but we are all the products of our training. Besides, I refer personally to H-type as 'background" BSE (BBSE) to avoid the confusion and to reflect my belief that H-type BSE has been around in NA for a long, long time.

Using this terminology BASE has so far not been confirmed in NA to my knowledge.

"Japan, the USA, Canada and several European countries (including France, the Netherlands, Sweden, Switzerland, and Germany) have reported H-type BSE. Japan and several European countries (including Italy, Denmark, Poland, Belgium and Germany) have reported L-type BSE. Both types have been reported predominantly in cattle over 10 years old. In both types, the abnormal prion protein (PrP Sc ) in these animals has different biochemical characteristics to that seen in BSE. Mice experimentally infected with the brains of these animals develop a disease which differs from that seen in BSE infected mice. In two L-type cases where the intact whole brain was studied, the pattern of deposition of PrP Sc in the brain differed from that in BSE."

 http://www.defra.gov.uk/news/2007/070309b.htm

On a not wholly unrelated note, it was only a matter of time until someone came up with a potential treatment regimen, or at least a means of slowing down CNS destruction by the (various?) BSE prions.

http://vir.sgmjournals.org/cgi/content/abstract/89/2/594

Memantine is an Alzheimer's treatment drug manufactured by Merz (not a typo). Stock up today.