Rustrela virus, a recently discovered and often fatal virus causing neurological illness in cats, has been identified in a mountain lion in Colorado, marking the first confirmed case in the US. This discovery raises concerns about the virus’s potential spread and impact on wildlife.
In May 2023, Colorado Parks and Wildlife officials responded to reports of a mountain lion exhibiting neurological symptoms, including impaired hind leg function, in a residential area of Douglas County. The animal was euthanized, and subsequent analysis revealed the presence of rustrela virus.
A mountain lion infected with rustrela virusA homeowner captured this video of the mountain lion struggling to move due to the neurological effects of the rustrela virus. Credit: Fox, et al/Emerging Infectious Diseases
Initial tests for common feline neurological diseases, such as rabies and Toxoplasma gondii, were negative. However, genetic analysis of the mountain lion’s brain and spinal tissue confirmed the presence of rustrela virus (Rubivirus strelense).
Rustrela virus, first identified in animals at a German zoo in 2020, has been linked to “staggering disease,” a rare but often fatal neurological illness affecting both domestic and wild cats in Europe since the 1970s. This case, published in Emerging Infectious Diseases, is the first documented instance of the virus and the associated disease in the US.
Image related to Rustrela Virus
This discovery raises many questions about the potential risks of rustrela virus. The strain found in the Colorado mountain lion is genetically distinct from European variants, suggesting the possibility of its endemic presence in the US. While the virus is known to infect various mammals, its potential to infect humans remains unknown.
Rustrela virus is closely related to the rubella virus, which can cause neurological complications in humans, particularly in unborn babies. However, rubella has been eliminated in the US through vaccination.
Comparison of Rustrela Virus and Rubella Virus
Researchers emphasize the importance of considering rustrela virus as a potential cause of neurological disease in North American mammals. The discovery, while concerning, enables further research to understand the virus’s prevalence, transmission, and potential impact on various species.
This finding facilitates targeted research efforts. Lead author Karen Fox, a former pathologist with Colorado Parks and Wildlife, stated that identifying the virus will make it easier to detect future cases. Collaborative efforts with European researchers will contribute to understanding the virus while ongoing surveillance continues in Colorado. Residents are encouraged to report sightings of mountain lions exhibiting similar symptoms to local wildlife officials.
https://www.nature.com/articles/s41586-020-2812-9
https://www.nature.com/articles/s41467-023-36204-w
https://wwwnc.cdc.gov/eid/article/30/8/24-0411_article#r1
https://pubmed.ncbi.nlm.nih.gov/9450233/
https://cpw.state.co.us/aboutus/Pages/News-Release-Details.aspx?NewsID=4189
