An international study led by French, Norwegian and Spanish scientists has shown that a European strain of Chronic Wasting Disease (CWD), detected in Norwegian elk, acquires increased cross-species infectivity after adapting to an intermediate host: transgenic mice expressing the ovine prion protein (VRQ genotype).

Initially, the original strain failed to infect human or bovine PrP models. However, after several passages in the sheep model, the prions adapted and were able to transmit effectively to mice with human PrP (codons 129M and 129V) and showed biochemical characteristics different from those of known human prion strains.

Los resultados apuntan a que ciertos priones de CWD podrían aumentar su potencial zoonótico tras propagarse en animales de granja como ovejas. This evidence, reminiscent of the case of bovine spongiform encephalopathy (BSE) in sheep and goats, underlines the urgent need to assess this risk under natural exposure conditions.