White-tailed deer in states from Pennsylvania to Wisconsin are being spotted with skin covered in fleshy bubbles. Photos and videos online show animals with tumor-like lumps on their heads, necks, and legs. While unsettling to see, experts say the growths are not new and have a clear cause.
Photo: Reddit / u/jakeymakeme
Deer across the US are turning up with large wart-like growths.
The Virus Behind the “Flesh Bubbles”
Wildlife agencies have identified the condition as cutaneous fibromas, often called deer warts. These growths are caused by a species-specific papillomavirus, similar to the viruses that trigger warts in rabbits or even humans. The Maine Department of Inland Fisheries and Wildlife explains that the tumors are firm, hairless, and can range from pea-sized bumps to masses as large as a football, sometimes clustering across a deer’s body, Unilad reports.
The Washington Department of Fish and Wildlife notes that papillomas are most common in late summer and fall, when biting insects are abundant. Mosquitoes and ticks transmit the virus as they feed, allowing it to spread through deer populations nationwide.
Photo: x / Bellamari8mazz
The condition is called cutaneous fibroma or deer warts.
How It Affects Deer
Most deer survive the infection. Their immune systems typically fight off the virus within a few months, and the growths dry up and fall away. But large clusters can cause problems, Metro reports. If the warts block vision, cover the mouth, or make walking difficult, the animals may struggle to feed or evade predators. In those rare cases, wildlife officials sometimes consider euthanasia. Fibromas are most often observed in young bucks, possibly because fighting and rubbing antlers on shared posts increase opportunities for transmission. Deer can also spread the virus by using the same feeding areas or bedding sites.
Not a Threat to Humans
Despite their grotesque appearance, the growths cannot spread to people, pets, or livestock. Each species has its own papillomavirus, and cross-infection does not occur, according to the Washington Department of Fish and Wildlife.
The virus spreads through mosquitoes and ticks.
Climate Change and a Surge in Cases
Scientists warn that warmer temperatures may be making the problem worse. Rising heat allows mosquitoes and ticks to thrive longer and in regions where they once struggled.
“These temperature changes are resulting in diseases that were never endemic in certain areas to become endemic,” Dr. Omer Awan of the University of Maryland School of Medicine told MailOnline.
That means more deer may show signs of fibromas in the years ahead. And while the disease is rarely fatal, its visual impact is spreading quickly, amplified by trail cameras, smartphones, and social media posts documenting the condition.
