Rabbits with 'Horns': The Shope Papillomavirus

A recent phenomenon in Fort Collins, Colorado, has captured public attention: cottontail rabbits exhibiting grotesque, horn-like protrusions. These rabbits, colloquially dubbed 'Frankenstein bunnies' or 'demon rabbits', have sparked curiosity and concern. However, scientists assert that this seemingly alarming condition is attributable to a well-documented viral infection.

The culprit behind these bizarre growths is the Shope papillomavirus, named after Dr. Richard E Shope, who first identified the disease in the 1930s. This virus induces the formation of keratinous growths on the rabbits' faces, which can resemble horns if they grow to a substantial length. While visually striking, the condition is generally benign and rarely interferes with the rabbits' vital functions unless the growths impede vision or eating.

Intriguingly, the Shope papillomavirus has played a significant role in both folklore and scientific advancement. It is believed to have inspired the North American jackalope myth, which describes horned rabbits. More importantly, research on this virus has contributed to our understanding of the relationship between viruses and cancer, including insights into human papillomavirus and cervical cancer.

Kara Van Hoose, a spokesperson for Colorado Parks and Wildlife, elucidates that sightings of infected rabbits are not uncommon, particularly during the summer months when arthropod vectors like fleas and ticks are most active. She reassures that the virus is species-specific, posing no threat to humans or other animals. Furthermore, rabbits possess the immunological capacity to combat the virus, leading to the eventual regression of the growths.