A peer-reviewed study, released in the January 2025 issue of the Emerging Infectious Disease Journal, has found evidence that wild pigs may be able to spread chronic wasting disease (CWD).
That disease, which is deadly to ungulates, is caused by an abnormal protein called a prion and can lead to the decimation of deer, elk, caribou, and moose herds. A cure has not been found for the disease.
The study’s researchers used a prion amplification test and identified prions in tissues of wild pigs living in the US in areas where CWD is prevalent. The pigs did not contract the disease, so it appears they have some resistance to CWD infection. The concern, however, is that there is a potential for pigs to move and shed infective prions across the landscape, which might lead to further spread of the disease. Ungulates that ingest the prions will contract the disease and eventually spread it further. Persistent shedding of prions by CWD-affected animals and resulting environmental contamination is considered a major route of transmission contributing to spread of the disease.
Wild pig populations are established in many US states and several Canadian provinces. Ontario’s small wild pig population is so-far being kept in check.
“This new research is proof-of-concept that wild pigs can spread CWD prions across the landscape, adding another level of concern for wildlife managers,” Ontario Federation of Anglers and Hunters Manager of Policy Mark Ryckman said. “Prions can be spread through multiple avenues, most of which are difficult or impossible to control. This reiterates the need to keep CWD from entering Ontario in the first place.”
