Frightening Disease Causes Partial Paralysis in Mountain Lions

A video from last May shows a mountain lion in Colorado struggling to stand and walk. Wildlife officials tranquilized and euthanized the animal after realizing it was very sick. New research from Colorado State University confirms that the mountain lion had staggering disease, a usually fatal condition that results from the rustrela virus. This is the first known case of staggering disease in North America.

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“On May 12, 2023, Colorado Parks and Wildlife (Denver, CO, USA) received a report of an ≈1-year-old free-ranging female mountain lion (Puma concolor) with signs of severe hind leg ataxia and paresis,” the research report says. “The animal was reluctant to rise and had markedly decreased capacity to move or bear weight on the hind end.”

After wildlife officials euthanized the mountain lion, researchers conducted a postmortem investigation to better understand the animal’s condition. They found the rustrela virus, which researchers say causes neurologic diseases among mammals, including staggering disease.

CDC defines staggering disease as “a usually fatal neurologic syndrome in cats.” It is more common in Europe, where researchers say it has affected a number of different mammal species, including domestic cats.

Watch the video of the mountain lion struggling with staggering disease here:

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