Exactly how virus carried by 'Frankenstein' rabbits growing black 'tentacles' spreads following urgent warning from experts
The United States is facing another pandemic, but thankfully, this one isn't expected to affect humans like the ravages of COVID-19. Feeling like Naughty Dog's The Last of Us video game and HBO's hit series of the same name come to life, rabbits in America have started sprouting tentacles from their mouths.
While Naughty Dog was inspired by the real-life cordyceps infection that tends to affect ants, there are numerous other horrifying animal diseases out there that could've served as source material.
With an outbreak of chronic wasting disease (CWD) creating 'zombie deer' in June 2023, we're now hearing reports of Frankenstein rabbits.
What is cottontail papilloma virus (CRPV)?
A bizarre virus is turning rabbits in the U.S. into grotesque, horned creatures with black, tentacle-like growths — and sightings are rising fast.
— Shadow of Ezra (@ShadowofEzra) August 12, 2025
Known as the cottontail papilloma virus (CRPV) or Shope papilloma virus, it causes tumors to develop on or near the rabbits’ heads.… pic.twitter.com/jGs5nzqjDt
A concerning number of rabbits in Colorado have been diagnosed with cottontail papilloma virus (CRPV), which is noticeable thanks to black spikes protruding from their heads, tentacles growing from their mouths, and slug-like growths obscuring their vision.
Social media has been filled with comparisons to Frankenstein's monster from Mary Shelley's Frankenstein, resembling some nightmarish hybrids between rabbits and a tentacled Cthulhu.
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The first case was reported by a man in Fort Collins, Colorado, which is a city about 65 miles North of Denver. The Colorado Parks and Wildlife confirms it has had over a dozen calls reporting sightings, with most concentrated in Northern Colorado.
Unfortunately, due to multiple reports possibly citing the same infected rabbit, it's hard to determine how bad the outbreak is right now.
Reports actually spread back to 2024, with Fort Collins resident Susan Mansfield stating: "It looked like black quills or black toothpicks sticking out all around its mouth. I thought he'd die off during the winter, but he didn't. He came back a second year – and it grew."
How is cottontail papilloma virus (CRPV) spread?
Similar to how the chikungunya virus caused concern in China, cottontail rabbit papillomavirus is spread between rabbits via biting insects like fleas and mosquitoes. This means infection rates are higher in summer due to an increase in insect activity.
Thankfully, Kara Van Hoose from Colorado Parks and Wildlife explained how the infection is mostly benign and can't spread to other species. Infected bunnies will typically overcome CRPV on their own, with it only becoming a problem if they're stopped from seeing or eating. Still, infected rabbits might exhibit 'gross' warts or horns.
Most household pets won't be affected, although pet rabbits should be kept inside if you see wild rabbits in the area.
As noted by the New York Times, a study from the National Institutes of Health claims that CRPV is more severe in domesticated rabbits and can cause cancer. If your pet rabbit is infected, you should immediately seek the help of a veterinarian.
There's no known cure or treatment for CRPV, although Van Hoose says there are several ways we can help the infected. Avoid feeding or approaching them, with Van Hoose concluding: "Nature is metal, and this can be kind of cool looking on different rabbits."
Some on social media thought the pictures were AI, with one person even joking: "One time I need this to be AI."
Unfortunately, for Colorado's Peter Rabbit wannabees, cottontail papilloma virus is very real.