While most people call any type of hair loss, itching and sores or inflammation on the skin of a dog mange, there are actually three different types of mange that can be problematic for dogs and dog owners. Mange is actually caused by one of three types of mites that are so small they cannot be seen with the naked eye. These microscopic trouble makers can live either in the skin or the hair follicle of the dog, depending on the type of mite that they are. There are two types of mange mites, the sarcoptic mange mite and the demodex canis mite, that can pass between dogs or puppies to humans and other pets in the house. The sarcoptic mange mite is very contagious but the demodex mange mite is rarely transferred between dogs and humans, but it can occur under the right conditions.
Sarcoptic mange is common in puppies and dogs, as well as several other species including humans. The common name for sarcoptic mange is scabies, and the small mites actually burrow into the skin resulting in a itching sensation. The mites lay eggs in the skin that then hatch and continue the cycle. The itching sensation is very pronounced and dogs and puppies will scratch and lick their skin, removing all hair and causing large lesions on the skin's surface and even deeper in extreme cases. This allows bacteria to enter the skin, causing often very severe secondary infections.
In humans the mites can only survive one generation, but in the dogs they can continue to thrive and multiply. It is essential to treat the dog or puppy as well as all bedding, toys, collars, leashes and brushes to completely eliminate the problem. Treatment is usually Ivermectin administered in two oral dosages as well as antibiotics and steroids to treat the skin itch and lesions. It may take weeks or even months for the skin to heal and the hair to grow back in.
This is usually a very mild type of mange seen on puppies that results in dry, flaky skin. It is often referred to as "walking dandruff" and usually will clear itself up in a few weeks. It is highly contagious between puppies but adult dogs seem to have an immunity which the puppies will also develop after they have had the condition once. The mites are relatively large and red in color and can be seen under a microscope. Humans are not considered to be at risk for developing any problems with this type of mange mite.
The demodex mange mite is present on all puppies, but for some reason not clearly understood it can become problematic in some puppies, particularly purebred lines that have a history of the condition. Puppies that are stressed also are more likely to develop this condition. In most cases the puppies can be treated with dips and baths and the small amount of hair lost during the infestation will quickly grow back. In severe cases there may be significant hair loss over the body and oozing, crusty lesions. This can be very problematic in older dogs and may required prolonged treatment. Dogs with demodectic mange may not be appropriate for breeding programs, especially if the infestation was severe or reoccurred when the dog was older.
Any treatment for mange should be supervised by a vet as some breeds, most specifically the Collie breeds, can have a severe reaction to the medications.