Reports of squirrels and deer covered in warts and lesions across several U.S. states have sparked alarm among netizens, with photos of the animals circulating widely on social media.

Residents from New York, Pennsylvania, and Wisconsin have shared images of squirrels and deer in backyards and wild areas, showing what appeared to be disturbing skin growths.

Experts, however, assure the public that the phenomenon, while unsightly, is more common than many realize. Wildlife specialists point to squirrel pox, also known as squirrel fibromatosis, as the likely cause in squirrels. The virus, which has been noted in Maine and Canada this 2025 but recorded as early as 2023, causes pus-filled blisters that spread across the animal’s body. Specialists stress that it is not cancerous and that most infected squirrels recover over time.

Meanwhile, deer showing similar symptoms have been diagnosed with cutaneous fibroma, more commonly known as deer warts. Both conditions are typically spread through insects such as mosquitoes and ticks, as well as direct contact or bodily fluids among animals of the same species.

Officials emphasize that while these viruses are not harmful to humans, people should avoid touching infected animals to prevent unnecessary risks.