Chronic wasting disease has always been considered an animal problem — a brain-wasting condition that kills deer, elk, and other cervids, causing visible deterioration that hunters and wildlife managers could observe and use to identify infected animals. A study published June 16, 2026, in Science Advances challenges that assumption at its foundation: infectious prions can be present and transmissible in animals that appear completely healthy, with no clinical signs of disease.
The research, conducted by scientists at the University of Calgary Faculty of Veterinary Medicine and international collaborators and covered by ScienceDaily on June 16, also confirmed limited but measurable transmission of CWD prions to nonhuman primates in laboratory settings — the most controlled form of primate testing available, and the most direct evidence yet that the species barrier between CWD and primates (the animal group most closely related to humans) is not absolute.
