Project 1401 - Live CWD Research on Elk herds in Saskatchewan

The Elk Research Council has announced the results of a 2014 project have been officially published. This project, known was ERC Project 1401- Live CWD Research on Elk herds in Saskatchewan, was a project in Saskatchewan for research to support development of a live test for Chronic Wasting Disease. The Elk Research Council, which serves as the North American Elk Breeders Association's 501(c)(3) animal health foundation, ordered the study with the help of the Saskatchewan Cervid Alliance. Dr. Nicolas Haley, previously with Kansas State University College of Veterinary Medicine, conducted the ante-mortem tissue sampling and research for Kansas State and also shared samples with Colorado State University.

Ante-mortem samples (blood, nasal brushes, and rectal biopsies) were taken from 120 elk in December 2014. The study's findings are as follows:

This study evaluated the sensitivity of the real-time quaking-induced conversion (RT-QuIC) assay of recto-anal mucosa-associated lymphoid tissue (RAMALT) biopsy specimens and nasal brushings collected ante mortem. These findings were compared to results of immunohistochemistry (IHC) analysis of ante- and postmortem samples. RAMALT samples were collected from populations of farmed and free-ranging Rocky Mountain elk (Cervus elaphus nelsoni; n = 323), and nasal brush samples were collected from a subpopulation of these animals (n = 205). We hypothesized that the sensitivity of RT-QuIC would be comparable to that of IHC analysis of RAMALT and would correspond to that of IHC analysis of postmortem tissues. We found RAMALT sensitivity (77.3%) to be highly correlative between RT-QuIC and IHC analysis. Sensitivity was lower when testing nasal brushings (34%), though both RAMALT and nasal brush test sensitivities were dependent on both the PRNP genotype and disease progression determined by the obex score. These data suggest that RT-QuIC, like IHC analysis, is a relatively sensitive assay for detection of CWD prions in RAMALT biopsy specimens and, with further investigation, has potential for large-scale and rapid automated testing of ante mortem samples for CWD.

Recently, Dr. Haley has also performed live test research on CWD positive whitetail herds in Iowa, Ohio and Pennsylvania.

"We are appreciative of the ERC and NAEBA's support of this project," said Dr. Haley, as he prepared for the trip to Canada. "Our objective in this proposal is to translate our prior pilot for both ante- and postmortem samples towards a more thorough evaluation of ante-mortem testing in captive and farmed cervids. This is an important step."

This research was carried out jointly between the Center of Excellence for Emerging and Zoonotic Diseases at Kansas State University, the National Institutes of Health at Rocky Mountain Laboratories, and the Prion Research Center at Colorado State University. The Canadian Food Inspection Agency has been very cooperative with the research project.

The study's publication in the Journal of Clinical Microbiology has been posted on the project's page on the Elk Research Council website.

Journal Publication: Seeded Amplification of Chronic Wasting Disease Prions in Nasal Brushings and Recto-anal Mucosa-Associated Lymphoid Tissues from Elk by Real-Time Quaking-Induced Conversion