If you follow news about dogs, you know what an extreme case of mange looks like. It's a common skin disease in dogs and puppies that are strays, neglected, or abused. These dogs appear to be beyond hope—hairless, with skin covered in sores or with thickened, hard, crusty patches. Such dogs are often described as having skin that appears to have turned to stone.
It's a horrible, painful condition, but as you've seen in the many “miracle dog” stories in the news, even serious cases can be treated effectively.
Take Scarlet, for example. One year ago, the then 4-month-old puppy was found at the side of the road in LaFollette, Tennessee, bald and covered with oozing sores and crusty skin, so frail that pieces of it would fall off when rescue workers from the Friends of Campbell County Animals touched her. Her eyelids had fused so she was blind, she could barely move, and many believed nothing could help her.
Yet one year later, after intensive treatment by veterinarians at the University of Tennessee, Scarlet is a happy, healthy pet. Her body is now covered with a coat of light caramel-colored hair, and the only reminders of her ordeal are scars on her face and back. She's a therapy dog, and it's now her job to cheer up hospital patients.
Scarlet's case is an extreme one, but not all that unusual for mange patients. Mange is a terrible disease, and it can kill. But, as with Scarlet, there are treatments that can return even the most seriously infected animals to health.
What Is Mange?
Mange refers to skin diseases caused by mites. The term is derived from a French word mangeue, which translates into “to eat or itch.” Mange, caused by different kinds of mites, affects many kinds of animals, including humans.
In dogs, there are two major forms of mange, each caused by different mites:
- Sarcoptic Mange (also known as scabies)
- Demodectic Mange (also known as red mange or demodex)
Also known as canine scabies, this disease is caused by a circular-shaped, eight-legged mite called the Sarcoptes scabiei. This form of mange is highly contagious. The parasite can be transmitted from dog to dog and can pass from dogs to humans, although it doesn't thrive on non-canine hosts. Female mites burrow into the skin to lay their eggs. The eggs hatch in about three weeks, and the young feed on the host's skin.
Symptoms of Sarcoptic Mange
Symptoms will generally appear about 10-days-to-8-weeks after contact with a dog carrying scabies. Typically, the first signs of the infection will be on the margins of the ears, chest, elbows, hocks, and belly. Untreated, they can quickly spread. The most common symptoms of sarcoptic mange include:
- Extreme itchiness
- Redness and rash
- Thick yellow crusts
- Hair loss
- Bacteria and yeast infections
- Thickening of the skin (advanced cases)
- Lymph node inflammation (advanced cases)
- Emaciation (extreme cases)
How Is Sarcoptic Mange Diagnosed?
A veterinarian will take one or more skin scrapings and look under a microscope for the presence of eggs or mites. Sometimes, however, no mites appear in the skin samples although the symptoms strongly suggest an infestation. So the vet may still treat the dog for sarcoptic mange, using the response as confirmation of the diagnosis.
Demodectic mange, or demodex, is caused by a cigar-shaped mite, Demodex canis. The difference from sarcoptic mange is that these are a normal part of the skin flora, always present, and usually harmless. They are passed to pups from their mothers in the first few days after birth. The mites take up residence deep in hair follicles and stay there, causing no trouble. A normal immune system keeps their numbers in check. But in a dog with a weakened immune system, they can grow out of control. Dogs at risk of demodectic mange include:
- Puppies who inherit a weakness in their immune systems will be prone to a particularly serious form of demodex, known as juvenile onset.
- Young healthy dogs may develop some patches of demodex, which sometimes go away on their own or with localized topical treatment.
- Elderly, sick, neglected, or stray dogs with weakened immune systems often develop demodex. For example, cancer or diabetes can impair immune function and lead to this form of mange.
Symptoms of Demodectic Mange
As with scabies, demodex is easy to spot.
- In localized cases, it shows up as patches of hair loss and red, scaling skin.
- In generalized cases, the entire body may be covered with redness, infections, scaling, swelling, and crusts. Often the dog loses most, if not all, hair.
Diagnosis of Demodectic Mange
Your veterinarian will take a skin scraping and look for mites under a microscope.
Treatment of Mange In Dogs
Both scabies and demodex will require treatments to heal the skin and control the mites. Some people are tempted to treat the condition without expert guidance, but it's prudent to see a veterinarian because even a mild case can grow quickly. Treatments for both forms of mange include several strategies:
- Hair clipping
- Dipping to cleanse and heal skin: Baths in medicated shampoos on a weekly basis will help heal and soften skin.
- Mite eradication and control: Topical applications of compounds to kill the mites, such as selamectin and imidacloprid-moxidectin formulations, over a period of several weeks have been shown to be effective. Oral treatments are also sometimes used.
Sources: The Merck Veterinary Manual, Companion Animal Parasite Council™