Chronic wasting disease

Other animal prion diseases. Outbreaks of transmissible mink encephalopathy and chronic wasting disease in captive populations of mink, mule deer and elk in certain regions of the U.S.A. have also been attributed to prion-infected foodstuffs, although the origin of prion infection is unclear [8], Epidemiological studies suggest lateral transmission as the most plausible explanation for the spread of chronic wasting disease in captive populations... 

Guiroy, D. C., Williams, E. S., Liberski, P. P., Wakayama, I., and Gajdusek, D. C. (1993a). Ultrastructural neuropathology of chronic wasting disease in captive mule deer. Acta Neuropathol. (Berl.) 85, 437-444. 

Fig. 20 Fluorescent images of prion deposits associated with distinct prion strains, murine chronic wasting disease (mCWD) (a) and murine sheep scrapie (mSS) (b), which has been stained by PTAA. (c) Correlation diagram of the ratios, R532/639 and R532/ max, of the intensity of the emitted light from PTAA bound to prion deposits originating from individual mice infected with CWD (black symbols) or sheep scrapie (purple symbols) [35]...

A misfolded protein appears to be the causative agent of a number of rare degenerative brain diseases in mammals. Perhaps the best known of these is mad cow disease (bovine spongiform encephalopathy, BSE), an outbreak of which made international headlines in the spring of 1996. Related diseases include kuru and Creutzfeldt-Jakob disease in humans, scrapie in sheep, and chronic wasting disease in deer and elk. These diseases are also referred to as spongiform encephalopathies, because the diseased brain frequently becomes riddled with holes (Fig. 1). Typical symptoms include dementia and loss of coordination. The diseases are fatal. 

Despite steady progress in non-bioassay discrimination of prion strains, the mouse bioassays remain superior. This was recently demonstrated when two strains of chronic wasting disease (CWD), a prion disease affecting cervids, with biochemically indistinguishable PrPSc aggregates, were recognized as separate CWD-1 and... 

Keywords Cervid prions Chronic wasting disease Prion containment Wild-life prion disease Zoonotic potential... 

Table 1 Summary of chronic wasting disease discoveries throughout the world (modified from www.cwd-info.org CWD timeline)...

Fig. 2 Clinical aspect and brain pathology. Upper picture shows a female mule deer, 3 years of age, with clinical signs of late chronic wasting disease, which include hypersalivation, emaciation and depression. Lower pictures depict amyloid plaques in the thalamus of a WTD with CWD. Left shows formalin-fixed, paraffin-embedded tissue stained with HE. Plaques are delineated with arrows. Right picture shows an immunohistochemical (IHC) staining of such amyloid plaques. Pictures kindly provided by the abatement of the late Beth Williams, University of Wyoming...

Baeten LA, Powers BE, Jewell JE, Spraker TR, Miller MW (2007) A natural case of chronic wasting disease in a free-ranging moose (Alces alces shirasi). J Wildl Dis 43 309-314... 

Williams ES, Young S (1980) Chronic wasting disease of captive mule deer a spongiform encephalopathy. J Wildl Dis 16 89-98... 

Walsh DP, Miller MW (2010) A weighted surveillance approach for detecting chronic wasting disease foci. J Wildl Dis 46 118-135... 

Joly DO, Samuel MD, Langenberg JA et al (2009) Surveillance to detect chronic wasting disease in white-tailed deer in Wisconsin. J Wildl Dis 45 989-997... 

Roels S, Saegerman C, De Bosschere H et al (2005) First results of chronic wasting disease (CWD) surveillance in the south-eastern part of Belgium. Vet Q 27 98-104... 

Miller MW, Conner MM (2005) Epidemiology of chronic wasting disease in free-ranging mule deer spatial, temporal, and demographic influences on observed prevalence patterns. J Wildl Dis 41 275-290... 

Dulberger J, Hobbs NT, Swanson HMet al (2010) Estimating chronic wasting disease effects on mule deer recruitment and population growth. J Wildl Dis 46 1086-1095... 

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