Early and Non-Invasive Detection of Chronic Wasting Disease Prions in Elk Feces by Real-Time Quaking Induced Conversion.
Chronic wasting disease (CWD) is a fatal prion disease of wild and captive cervids in North America. Prions are infectious agents composed of a misfolded version of a host-encoded protein, termed PrPSc. Infected cervids excrete and secrete prions, contributing to lateral transmission. Geographical distribution is expanding and case numbers in wild cervids are increasing. Recently, the first European cases of CWD have been reported in a wild reindeer and two moose from Norway. Therefore, methods to detect the infection early in the incubation time using easily available samples are desirable to facilitate effective disease management. We have adapted the real-time quaking induced conversion (RT-QuIC) assay, a sensitive in vitro prion amplification method, for pre-clinical detection of prion seeding activity in elk feces. Testing fecal samples from orally inoculated elk taken at various time points post infection revealed early shedding and detectable prion seeding activity throughout the disease course. Early shedding was also found in two elk encoding a PrP genotype associated with reduced susceptibility for CWD. In summary, we suggest that detection of CWD prions in feces by RT-QuIC may become a useful tool to support CWD surveillance in wild and captive cervids. The finding of early shedding independent of the elk's prion protein genotype raises the question whether prolonged survival is beneficial, considering accumulation of environmental prions and its contribution to CWD transmission upon extended duration of shedding.
Dept. of Ecosystem and Public Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, Canada.
Yo Ching
YC
Cheng
Dept. of Ecosystem and Public Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, Canada.
Samia
S
Hannaoui
Dept. of Molecular Biology, University of Wyoming, Laramie, United States of America.
Theodore R
TR
John
Canadian Food Inspection Agency, Lethbridge Laboratories, Lethbridge, Canada.
Sandor
S
Dudas
Canadian Food Inspection Agency, Lethbridge Laboratories, Lethbridge, Canada.
Stefanie
S
Czub
Dept. of Ecosystem and Public Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, Canada.
Sabine
S
Gilch
D000818:Animals; D062207:Brain-Computer Interfaces; D003670:Deer; D005243:Feces / Q000737:chemistry*; D011328:Prions / Q000032:analysis*; D011994:Recombinant Proteins; D034081:Wasting Disease, Chronic / Q000175:diagnosis*
D011328:Prions; D011994:Recombinant Proteins