Shope papillomavirus (SPV) is a naturally occurring DNA virus that causes benign, wart-like growths on the heads and necks of cottontail rabbits. According to Colorado Parks and Wildlife and PetMD, the virus is transmitted primarily through insect vectors like mosquitoes and ticks. While the growths are usually non-fatal, they can lead to secondary health complications, and the virus is considered a significant historical milestone in cancer research, having helped scientists link viral infections to tumor development.
Why are these rabbits appearing in viral social media posts?
The recent surge in images showing rabbits with horn-like growths is a result of social media algorithms amplifying a long-standing wildlife phenomenon. While posts on platforms like Reddit describe the animals as “Frankenstein rabbits,” Colorado Parks and Wildlife spokesperson Kara Van Hoose clarified to Fox Weather that these are simply warts. Scientists believe these infected rabbits likely inspired the folklore surrounding the “jackalope,” a mythical creature from North American gift shops that features similar antler-like appendages.
Shope papillomavirus was the first DNA virus ever proven to cause tumors in animals. This 1930s discovery provided the foundational evidence that eventually led to the development of human HPV vaccines.
Is Shope papillomavirus a threat to humans or pets?
There are no documented cases of Shope papillomavirus transmitting to humans, according to The Open Sanctuary Project. The virus is strictly species-specific to rabbits and hares. However, domestic rabbits face a higher risk than their wild counterparts. PetMD reports that captive rabbits can contract the virus if exposed to wild carriers or insect vectors, and they are more susceptible to the growths turning into squamous cell carcinoma, a malignant form of cancer.
How can you protect your pet rabbit?
Veterinary experts recommend several proactive steps to minimize the risk of infection for indoor and outdoor rabbits:
- Vector Control: Screen enclosures to prevent mosquitoes, ticks, and fleas from reaching your rabbit.
- Isolation: Prevent any direct contact between domestic rabbits and wild cottontails.
- Monitoring: Inspect your rabbit’s head and neck area regularly for unusual skin growths.
- Veterinary Intervention: If you spot a growth, consult a veterinarian immediately. Surgical removal is a standard and effective treatment option.
What is the prognosis for an infected rabbit?
Most wild cottontails survive the infection, with the growths often regressing on their own once the immune system clears the virus, according to Colorado Parks and Wildlife. The primary danger arises when the papillomas grow large enough to obstruct the rabbit’s vision or mouth, leading to starvation or an inability to function. While the virus itself is not inherently painful, the secondary physical impairments can be fatal in severe, untreated cases.
Frequently Asked Questions
Can humans catch this virus from a rabbit?
No. According to PetMD, there is no evidence of human transmission of the Shope papillomavirus.
Are these growths actually horns?
No. They are keratinized skin growths, or warts, caused by the virus, not skeletal or bony structures.
Should I be worried if I see a rabbit with these growths?
You do not need to be personally alarmed, but you should avoid handling the animal. Contact your local wildlife agency if you are concerned about the rabbit’s welfare.
Pro Tip: If you live in an area where SPV has been reported, focus on flea and tick prevention for all household pets, as these insects act as the primary bridge for the virus to enter your home environment.
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