Each year, the Wildlife Center admits a variety of wild animals affected by mange. We also receive many phone calls about animals who appear to have this disease. Mange is currently the subject of much research in the wildlife world; learn more about this emerging disease and the Wildlife Center’s research on mange treatment.
What is mange?
Mange is a contagious skin disease caused by mites. There are a few different types of mange, each caused by a different mite species.
Sarcoptic mange, caused by the Sarcoptes scabiei mite, is the most common. These mites burrow into the outer layer of an animal’s skin and form tunnels. Female mites lay eggs within the tunnels; within three days, larvae hatch and either move in the tunnels, or move to the surface of the infected animal’s skin. Within days to weeks, the larvae develop into nymphs, which then develop into adult mites – ready to repeat the cycle. Manage treatment can be difficult since larvae, nymphs, and adults can all be living on the same host in different life stages.
Demodectic mange, caused by Demodex mites, is less commonly seen in wildlife but is often seen in dogs. This species of mite inhabits hair follicles and can be regularly found on animals. In a healthy animal, low numbers of these mites cause no symptoms and are simply a regular part of normal skin microfauna. In immunocompromised animals, the mites quickly multiply and can cause hair loss and severe illness.
Audycoptic mange, caused by the Ursicoptes americanus mite, is a bear-specific mange. This disease is similar to sarcoptic mange, but only affects bears. Secondary skin infections typically aren’t quite as severe as in sarcoptic mange cases.
What animals are affected?
Mange affects a variety of mammals – most notably foxes and other canids, bears, coyotes, rabbits, squirrels, and raccoons. Sarcoptic mange is a zoonotic disease – domestic mammals and humans can also contract the disease: depending on the type of mange and the species of the host, some infections may be self-limiting.
Mange is an emerging wildlife disease and the focus of many studies. Sarcoptic mange, in particular, is being reported in new geographic areas, in increasing numbers. Virginia has noted a significant mange issue in Black Bears in the Winchester area; Pennsylvania is also noting an increase in affected bears. Biologists and researchers are working toward learning more about this disease.
Can humans get mange?
There is a specific variety of the S. scabiei mite that causes scabies in people; humans can become infected with other varieties of the S. scabiei mites (from wildlife or domestic animals) and may develop a short-lived infection.
How is mange spread?
Mites are transferred to new hosts when the affected animal comes into direct physical contact with others. Larvae and nymphs may also fall off the host animal and can survive in the environment for several weeks. If an uninfected animal encounters a contaminated environment (e.g., moving into a shared nest or den), the mites can infect the new animal.
It’s important to note that some animals are exposed to mange mites and do not show any signs of infection; why certain animals are more affected is a subject of current research. Factors include host species, mite variety, and general host health and immunity.
What are the symptoms of mange?
Animals affected by sarcoptic mange often exhibit intense itchiness, hair thinning and loss, thickened skin, and scabbing. Hair loss is typically most pronounced around the animal’s face and ears. The infected animal may also develop a secondary bacterial skin infection, noted by additional foul-smelling crusts.
Severely affected animals will become thin, depressed, and lethargic. Although affected animals are usually physically capable of eating, they often cannot consume enough calories to support themselves nutritionally while also trying to fight off the disease. Some animals will develop compromised sight/hearing due to the severity of crusting around the ears/eyes.
Animals infected with demodectic mange also experience hair loss with dry, thickened skin. Because affected animals are typically those that are already immunocompromised, animals are also typically in poor body condition.
How is mange diagnosed?
Mange can’t be diagnosed by symptoms only; there can be several causes of hair loss in animals, including ringworm, bacteria, other parasites, or even routine shedding.
A definitive diagnosis is made by examining samples from skin scrapings under a microscope to look for mange mites. Typically, multiple skin scrapes are needed since mites may be in different life stages on different parts of the body.
Animals with mange also usually need additional diagnostics to confirm secondary bacterial infections.
Can mange be treated?
Mange can be successfully treated by administering medication that kills the mites. The successful treatment of mange is currently a significant focus of research; biologists, veterinarians, and other wildlife professionals are exploring new medications that can be used more effectively to treat affected wildlife.
Typical treatment includes administering an oral or injectable anti-parasitic drug to the animal; sometimes antibiotics and anti-inflammatories are also prescribed to treat secondary infections in severely affected animals. Severely affected animals may not survive despite treatment; while the mites may be killed with the medication, the animal’s body condition and overall health may be too comprised for recovery.
It’s important to note that each affected animal needs to be individually treated based on body weight and other factors; it’s not safe [or legal] to attempt to leave medicated food for an animal in an outdoor environment. While it may be tempting to leave medication-laced food for an affected animal, there is often no guarantee that the correct animal will receive the medications.
The Center’s Research on Bear Mange
In 2017, Dr. Peach Van Wick, the Center’s veterinary research fellow, began a study on a new drug for treating bear mange. If proven safe and successful, this one-time treatment could be applied in the field, which means fewer afflicted bears would need to go through the stress of capture, transport, and treatment at a wildlife rehabilitation center.
Bears at the Wildlife Center who took part in the study:
- Black Bear #17-1298. This adult female bear was admitted with severe mange. After a one-time treatment, the bear made marked improvement and was able to be released after just three months. A GPS collar on the bear enabled biologist to track her nearly a year after treatment and confirm that the bear did not have mange.
- Black Bear cubs of 2018. The 10 cubs participating in this portion of the study did not have mange, but each received a single dose of the medication; Dr. Peach performed weekly blood analyses for 10 weeks to learn more about how long the medication stays in a bear’s system.
- Black Bear #18-1952. This adult female bear was severely affected by mange and was missing about 90% of her hair. After a single dose of the medication and only two months of recovery, she was able to be released. This bear was also fitted with a GPS collar for post-release tracking.