Unusual Rabbit Growths Spark Concern, But There’s No Need to Panic

Scrolling through Reddit, you might stumble upon a bizarre sight: a cottontail rabbit from Colorado flaunting some dark, twisted formations on its head, almost like a scene from a Guillermo del Toro film. It’s unsettling, to say the least. And, images like this are popping up from places like Wisconsin, Minnesota, and New York, causing a mix of alarm and disbelief. Yet, wildlife officials aren’t raising any red flags. What’s actually going on here? It’s the Shope papillomavirus, a virus specifically affecting rabbits that scientists have been familiar with since the 1930s. So, it’s not new, just… trending.

What’s Really Growing on These Rabbits?

The striking visuals have a surprisingly dull explanation: they’re warts.

The Shope papillomavirus, or cottontail rabbit papillomavirus (CRPV), is a DNA virus that causes dark, wart-like growths on various parts of a rabbit’s head, ears, neck, and face. In serious instances, these growths can cluster and form a shape that resembles a keratinized crown. Kara Van Hoose, a spokesperson for Colorado Parks and Wildlife, summed it up by saying they’re more accurately described as “just warts.” Interestingly, those souvenir jackalopes you see in gift shops might have originated from rabbits infected with this virus.

Fortunately, most infected cottontails manage to pull through. As noted by Colorado Parks and Wildlife, “most infected cottontails can survive the viral infection, after which the growths will disappear.” However, severe cases can lead to complications. Papillomas have the potential to evolve into squamous cell carcinoma. Large growths can even obstruct a rabbit’s eyes or mouth, resulting in starvation or significant functional issues.

The virus itself doesn’t inflict pain, but the consequences can be serious.

Should You Be Concerned About Your Health or Your Pets?

SPV is a rabbit-centric issue, not a threat to humans — yet pet owners should still be cautious.

Shope papillomavirus infects only rabbits and hares. There are no reported cases of it affecting humans — not through bites or contact — according to PetMD and The Open Sanctuary Project. The transmission primarily happens between rabbits via mosquitoes, ticks, and fleas, rather than direct interaction. So, while it’s alarming to see these images online, social media has simply amplified a concern that’s been around for decades.

If you own a domestic rabbit, it’s smart to be vigilant. Pet rabbits can get SPV from wild carriers or shared insects, and when they do, they often face more severe effects, including a higher likelihood of malignant changes, according to PetMD. Here are some tips to minimize your rabbit’s risk:

• Keep domestic rabbits indoors or in secured areas if you’re in affected regions.
• Manage mosquito and tick populations around your yard.
• Prevent any contact between your rabbit and wild cottontails.
• Consult a veterinarian if you notice any suspicious wart-like growths on your rabbit’s head or neck; surgical removal is usually straightforward, and some growths may regress spontaneously.

Here’s a fascinating twist: Shope papillomavirus was the first DNA virus that scientists proved could cause tumors in animals. This pivotal discovery not only linked papillomaviruses to cancer but also influenced the development of HPV vaccines for humans. Oddly enough, the rabbit with the horror-movie appearance has played a role in protecting millions from cervical cancer through advancements in cancer vaccine research.