I've just completed a research review paper for a class on CWD.

The only test approved by the USDA, at this time, is that of immunohistochemical (IHC) staining of brain tissue. However, there are currently other tests being developed. Although CWD, scrapie and vCJD infections also demonstrate prion presence within the lymphatic system, testing of the lymph nodes is not approved for detection.

Tonsillar biopsies and subsequent IHC staining studies have been conducted on both deer and humans, with promising results. Those people suspected of vCJD (from BSE) usually undergo intense psychological testing , ultrasound/radiograms and tonsillar biopsies.

I copied the following paragraph from my paper, which may prove interesting:

Results confirming the efficiency of a specific prion immunoassay were published in October of 2002. This particular immunoassay measures specific antibody binding to both native and denatured forms of the prion protein. If successfully applied to domesticated livestock and free-ranging deer populations, this assay may be able to detect single infected animals in suspected areas of TSE contamination (The full reference follows: Safar JG, Scott M, Monaghan J, Deering C, Didorenko S, Vergara J, Ball H, Legname G, Leclerc E, Solforosi L, Servan H, Groth D, Burton DR, Prusiner SB, Williamson RA. 2002. Measuring prions causing bovine spongiform encephalopathy or chronic wasting disease by immunoassays and transgenic mice. www.nature.com/naturebiotechnology).

This new assay has generated much hype, and could not only increase efficiency but greatly decrease costs. IHC examinations are not only time-consuming, but require multiple personnel and specialized equipment, especially when taking bioptic samples from live animals.

For more information on CWD, approved methods of detection and the joint plan initiated this past summer by the USDA and USDI, go to
www.usda.gov

Hope this helps,

S&R