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Each summer I start to notice the squirrels in our backyard have ulcers, and loss of fur, on their bodies. What is this-----does it clear up on it's own----or can it cause their death? It seems to be fairly prevalent in our population of squirrels.

Wildlife Expert - Ken Burton

My guess is that you're talking about squirrel pox, also called squirrel fibroma, which is a viral disease affecting gray and fox squirrels in many areas. It causes tumors and, in severe cases, organ failure, blindness, and death. Most infected squirrels probably recover from it, and it seems to have no impact on overall population levels. There is no known prevention or treatment, and it cannot be transmitted to humans. You probably notice it at this time of year because it affects mostly juveniles and because squirrel population levels are at their highest now.

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