The first documented case of trout whirling disease in Canada was detected in August 2016 at Johnson Lake, in Banff National Park. The parasite responsible for the disease, Myxobolus cerebralis, is native to Europe and was introduced to North America in Pennsylvania in 1956. It has subsequently spread westward across the continent. Surveillance is currently being conducted to determine if it has spread further into Canadian waters.
Article from the Freshwater Fisheries Society of BC on Whirling Disease