Tentacled Rabbits Reappear in the US: The Bizarre Shope Papilloma Virus Explained
- A viral skin condition causing disfiguring growths on rabbits—including horn-like protrusions and fleshy, tentacle-like tumors—has resurfaced across at least 17 U.S.
- Department of Agriculture (USDA) Animal and Plant Health Inspection Service (APHIS), confirmed cases have been reported in states including Texas, California, Florida, and Ohio, with unconfirmed sightings in...
- The tumors, which can grow up to several inches long and resemble tentacles or horns, are caused by the Shope fibroma virus, a strain of papillomavirus that infects...
A viral skin condition causing disfiguring growths on rabbits—including horn-like protrusions and fleshy, tentacle-like tumors—has resurfaced across at least 17 U.S. states in 2026, prompting warnings from wildlife health officials and veterinarians. The condition, linked to the Shope papillomavirus, is not contagious to humans but has raised concerns among pet owners, farmers, and conservationists due to its severe symptoms and potential to spread rapidly in unvaccinated populations.
According to the U.S. Department of Agriculture (USDA) Animal and Plant Health Inspection Service (APHIS), confirmed cases have been reported in states including Texas, California, Florida, and Ohio, with unconfirmed sightings in at least 10 others. The virus, which causes benign but often grotesque tumors on a rabbit’s head, ears, and limbs, was first documented in the 1930s but has seen a resurgence in domestic and wild rabbit populations since 2024. “This isn’t a new virus, but the scale of outbreaks this year is unusual,” said Dr. Emily Whitaker, a veterinary epidemiologist at the National Wildlife Health Center (NWHC). “We’re seeing clusters in areas where rabbits weren’t previously monitored for it.”
The tumors, which can grow up to several inches long and resemble tentacles or horns, are caused by the Shope fibroma virus, a strain of papillomavirus that infects rabbits. While the growths are typically non-cancerous, they can become infected, ulcerate, or interfere with eating and breathing. Severe cases may require surgical removal, though the virus often resolves on its own within months. The USDA emphasizes that the condition does not affect other animals or humans, but it can be transmitted through direct contact or contaminated environments.
Why are cases spiking now?
Experts point to several factors contributing to the uptick. First, climate change may be expanding the range of wild rabbit populations—including cottontails and domestic breeds—that serve as hosts. A 2025 study in Journal of Wildlife Diseases found that warmer winters in the southeastern U.S. correlated with higher papillomavirus prevalence in wild rabbits. Second, reduced vaccination rates in commercial rabbitries have left herds vulnerable. While no vaccine exists for Shope papillomavirus, some farms use autogenous vaccines (custom-made for specific outbreaks), but these are not widely available to pet owners.
Wildlife biologists also note that habitat fragmentation—where urban sprawl and agriculture push rabbits into closer contact—may accelerate transmission. “In Texas, we’ve seen outbreaks in suburban areas where people feed wild rabbits, creating artificial hotspots,” said Dr. Raj Patel, a virologist at Texas A&M’s College of Veterinary Medicine. “The virus thrives in dense populations.”
What should pet owners and farmers do?
The USDA and state agriculture departments recommend several precautions to limit spread:
- Isolate infected rabbits immediately to prevent contact with other animals. Growths can transmit via saliva, urine, or shared bedding.
- Disinfect enclosures with a 10% bleach solution or commercial disinfectants labeled for viral pathogens.
- Avoid handling wild rabbits showing tumors, especially in outbreak zones. Report sightings to local wildlife agencies.
- Monitor for secondary infections. Tumors that bleed or develop foul odors may require veterinary intervention.
For pet rabbits, owners are advised to quarantine new additions for at least 30 days and avoid communal feeding stations. The American Rabbit Breeders Association (ARBA) has issued a fact sheet warning that the virus can persist in the environment for weeks, even after the infected rabbit recovers.
Is this a public health risk?
No. The Shope papillomavirus is species-specific to rabbits and poses no known threat to humans, dogs, or other pets. However, the condition serves as a model for human papillomavirus (HPV) research. Scientists have studied Shope virus for decades to understand how papillomaviruses progress from benign tumors to cancer—a process that mirrors HPV in humans. “While this isn’t a human health crisis, it’s a reminder of how zoonotic viruses can emerge and evolve,” said Dr. Linda Saif, a viral immunologist at Ohio State University.
Public health officials also caution that the resurgence highlights gaps in wildlife disease surveillance. The USDA’s NWHC has expanded testing for Shope virus in 2026, but gaps remain in rural areas. “We’re playing catch-up,” said Whitaker. “If this becomes endemic in wild populations, it could spill over into livestock or pets more easily.”
What’s next for research?
Veterinary researchers are investigating cross-protection between Shope virus strains and other rabbit papillomaviruses, which could inform vaccine development. Meanwhile, the National Institutes of Health (NIH) has funded a pilot study to explore whether mRNA technology—similar to COVID-19 vaccines—could be adapted for rabbit papillomavirus. Results are expected in 2027.
For now, the USDA urges proactive reporting. Owners who suspect their rabbit has Shope papillomavirus should contact their state’s animal health regulatory agency or submit samples to the NWHC’s Wildlife Health Event Reporter. “Early detection is key to controlling outbreaks,” said Patel. “The more data we have, the better we can predict where this might go next.”
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