Rabbits in northern Colorado are infected with harmless Shope papillomavirus, causing keratin growths on their faces, typically clearing up without intervention.
Rabbits with 'horns' in Colorado are being called 'Frankenstein bunnies.' Here's why
The cottontails recently spotted in Fort Collins are infected with the mostly harmless Shope papillomavirus, which causes wart-like growths that protrude from their faces like metastasizing horns.