Mucosal transmission and pathogenesis of chronic wasting disease in ferrets

Institute of Veterinary, Animal and Biomedical Sciences, Massey University, New Zealand
Journal of General Virology (Impact Factor: 3.18). 10/2012; 94(Pt_2). DOI: 10.1099/vir.0.046110-0
Source: PubMed


Chronic wasting disease (CWD) of cervids is almost certainly transmitted by mucosal contact with the causative prion, whether by direct (animal to animal) or indirect (environmental) means. Yet the sites and mechanisms of prion entry remain to be further understood. Here we sought to extend this understanding by demonstrating that ferrets exposed to CWD via several mucosal routes develop infection, PrPCWD amplification in lymphoid tissues, neural invasion, and florid TSE lesions resembling those in native cervid hosts. Ferrets developed extensive PrPCWD accumulation in the nervous system, retina, and olfactory epithelium, with lesser deposition in tongue, muscle, salivary gland and the vomero-nasal organ. PrPCWD accumulation in mucosal sites, including the upper respiratory tract epithelium, olfactory epithelium and intestinal Peyer's patches make the shedding of prions by infected ferrets plausible. We also observed that regionally targeted exposure of the nasopharyngeal mucosa resulted in an increased attack rate when compared with oral exposure. The latter finding suggests that nasal exposure enhances permissiveness to CWD infection. The ferret model has further potential for investigation of portals for initiation of CWD infection.

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