DENVER — A new study published in the journal Emerging Infectious Diseases reported the first finding of a deadly virus in a mountain lion in North America.
In May 2023, Colorado Parks and Wildlife euthanized a sick mountain lion in Douglas County that was having trouble using its hind legs.
Through an analysis of the animal's tissues, researchers found the presence of the rustrela virus, which has been identified as the cause of staggering disease. The disease is a fatal neurologic syndrome found in domestic cats, according to Colorado Parks and Wildlife.
Former Colorado Parks and Wildlife Pathologist Dr. Karen Fox was the lead author on the paper. Fox said that the diagnosis was challenging, and confirmation was only possible through collaboration with researchers in Germany.
Fox said it is not known how widespread the virus is in either domestic cats or wildlife populations. In Europe, the virus is not only found in cats but in other species including rodents, marsupials and a donkey, Colorado Parks and Wildlife said.
“Now that we know what we’re looking for, it should be easier to find new cases if they are out there,” Fox said. “With continued collaboration, we plan to learn what we can from our colleagues in Europe while we continue to look for new cases of staggering disease here in Colorado.”
Veterinarians at Colorado State University and Colorado Parks and Wildlife will be looking carefully for new cases. If anyone sees a mountain lion acting abnormally, staggering or having trouble walking, they should contact the local Colorado Parks and Wildlife office.