Researchers who late last week reported finding chronic wasting disease (CWD) prions in the muscles of infected moose, red deer, and reindeer in Norway say the discovery raises questions about the risk of human exposure through eating the meat of infected cervids (members of the deer family).
CWD is a fatal neurodegenerative cervid disease caused by prions, infectious proteins that trigger abnormal folding in normal proteins, especially in the central nervous system (CNS). Infected animals shed CWD prions in body fluids, which can spread to other cervids through direct contact or the environment.
The authors note that previous studies of cervids infected with North American CWD prion strains have detected prions in lymphoid tissues, peripheral nerves, muscles, blood, and excreta. But this was the first identification of European CWD prion strains in cervid muscle. The study was published in Emerging Infectious Diseases.
“The tissue distribution of PrPSc [CWD prions] in reindeer, with a CWD strain similar to cases found in North America, was therefore not surprising,” the researchers wrote. “However, the findings of PrPSc in peripheral tissues in moose and red deer by PMCA [protein misfolding cyclic amplification] were less expected, especially in muscles, given the sporadic occurrence and lack of evidence, to date, for contagiousness of these new CWD strains.”