What’s With the Weird Lumps on This Deer? Experts Weigh in

The Washington Department of Fish and Wildlife (WDFW) has been fielding calls lately about some weird lumps on deer. People are particularly concerned about chronic wasting disease (CWD), which WDFW defines as a fatal illness of cervids. In Washington State, native cervids include white-tailed deer, black-tailed deer, mule deer, elk, and moose. Weird lumps aren’t a symptom of CWD, though, according to WDFW. So what in the world are those lumps?

“At WDFW’s Region 1 office, we’ve been receiving calls recently regarding growths and abscesses on deer,” WDFW writes in an Instagram post earlier this week. “Two common causes of growths on deer are Caseous Lymphdenitis (CL) and Papillomas (warts), not CWD.”

WDFW’s website says CL is a condition “that can produce lumpy swellings and abscesses in the lymph node area of the head, neck, and groin.” The department says this condition is rare but does occasionally pop up in white-tailed and mule deer in Washington and beyond. CL can spread to other animals (including humans) through contact with ruptured abscesses, contaminated soil or feed, and flies. Transmission to humans is very rare, though.

Papillomas are growths on the skin that can occur anywhere on the outside of an animal’s body. WDFW says papillomas are firm, hairless, gray or black in color, can be smooth or rough in texture, as small as peas or as large as footballs, and may grow in clusters.

A virus causes these growths, and the virus is contagious within the same species but not outside of it. Therefore, it does not spread from deer to humans.

“Typically, papillomas will eventually outgrow their blood supply and fall off,” WDFW’s website says.

See a deer and its weird lumps, which appear to papillomas, here:

The Washington Department of Fish and Wildlife (WDFW) has been fielding calls lately about some weird lumps on deer. People are particularly concerned about chronic wasting disease (CWD), which WDFW defines as a fatal illness of cervids. In Washington State, native cervids include white-tailed deer, black-tailed deer, mule deer, elk, and moose. Weird lumps aren’t a symptom of CWD, though, according to WDFW. So what in the world are those lumps?

“At WDFW’s Region 1 office, we’ve been receiving calls recently regarding growths and abscesses on deer,” WDFW writes in an Instagram post earlier this week. “Two common causes of growths on deer are Caseous Lymphdenitis (CL) and Papillomas (warts), not CWD.”

WDFW’s website says CL is a condition “that can produce lumpy swellings and abscesses in the lymph node area of the head, neck, and groin.” The department says this condition is rare but does occasionally pop up in white-tailed and mule deer in Washington and beyond. CL can spread to other animals (including humans) through contact with ruptured abscesses, contaminated soil or feed, and flies. Transmission to humans is very rare, though.

Papillomas are growths on the skin that can occur anywhere on the outside of an animal’s body. WDFW says papillomas are firm, hairless, gray or black in color, can be smooth or rough in texture, as small as peas or as large as footballs, and may grow in clusters.

A virus causes these growths, and the virus is contagious within the same species but not outside of it. Therefore, it does not spread from deer to humans.

“Typically, papillomas will eventually outgrow their blood supply and fall off,” WDFW’s website says.

See a deer and its weird lumps, which appear to papillomas, here: