What To Do About Demodectic Mange

by Nicola Parry, DVM

Mange is the term for skin disease due to mite infestation, and there are two different forms of this condition in dogs, caused by different mite species. One of these is demodectic mange (or demodecosis).

What Causes This Condition?

This form of mange is caused predominantly by a mite called Demodex canis that lives deep in the skin, mostly in or around hair follicles. This parasite is very common, and is found on most dogs, but causes no problems for the majority of them. It tends only to progress to cause demodectic mange under certain conditions. Most cases tend to occur in young dogs that are 12-18 months of age and do not yet have a very mature immune system. As dogs get older, their immune system matures, and they tend to be less susceptible to demodecosis. Adult dogs with demodectic mange therefore tend to be those with defective immunity – this enables the mite to “get the upper hand” in some way, allowing them to multiply in the skin.

4 Signs Often Associated With Demodectic Mange

1. Patchy hair loss (often starting on the face, especially around the eyes)
2. Thickened, wrinkled skin
3. Foul smelling skin with red scabs (due to secondary bacterial infection)
4. Itchiness

How Is It Treated?

It is important to have your dog checked by his veterinarian if you suspect he might have demodectic mange, since other skin disease can appear similar and must therefore be ruled out. Additionally, many cases of demodecosis won’t resolve without help, and if left untreated, may even worsen due to secondary bacterial infection. Different treatment options are available, and your veterinarian will advise you which is best for your dog, according to which form of the condition he has:

• Localized: This is more restricted to the face, and most cases resolve without treatment. If necessary, however, topical anti-mite treatments can be effective.
• Generalized: This form can be hereditary. It causes hair loss across the whole bodyand can be tricky to control.Therapy involves the use of medicated shampoos and dips, although some cases may be treated with off-label medications under close supervision of your veterinarian.
• Secondary bacterial involvement: Any case involving secondary bacterial infection requires antibiotic treatment in addition to anti-mite therapy.

Although some dogs can become very itchy, the use of corticosteroids is not advised since these drugs tend to suppress the immune system further, and may simply worsen the problem. If your dog is itchy, instead try the HappyTails oatmeal shampoo and conditioner for a more natural way to soothe the skin.

Is Demodectic Mange Contagious?

For the most part, demodectic mange is not considered contagious to other dogs. Since the mite lives deep in the skin within hair follicles, it is not a condition that is easily transferred by contact. The mite itself can be transferred from dog to dog, however, but unless it is transmitted to a dog with a defective immune system, demodecosis will not occur. Similarly, the condition does not seem to transmit from dogs to cats, or from dogs to people.

Can The Condition Recur After Treatment?

Since demodectic mange is really a problem that revolves around a defective immune system rather than simply the presence of mites, relapse is certainly possible if the dog comes into contact with more mites. Additionally, due to the likelihood that an inherited immune susceptibility is associated with cases of generalized demodecosis, dogs that have suffered from this form of the condition should not be bred.