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DEMODEX

This is a particular nasty mite that lives in the skin of dogs.

It is usually seen in young pets, or older pets whose immune system is not working efficiently for some reason e.g. another illness, on cortisone therapy.

Transmission

Dogs catch the mites from infected "carriers" who may appear to have relatively normal skin. On close examination of these carriers, typical lesions are usually evident.

In the case of puppies, its usually the mother who has Demodectic mange, and this can be a indication of poor breeding practices.

In adult dogs, its does not appear to spread as easily as in young puppies. Usually, the infected dog's immune system is not working as well as it should be at the time of infection e.g. in season, pregnant, other illness, on immune suppressing drugs such as cortisone. The mites find it easy to take control and spread over the whole body.

Symptoms

Juvenile cases appear as patches of hair loss over parts of the body. The coat looks a bit "moth eaten". If the lesions get infected with bacteria as well as the Demodex mage mite, they can become quite itchy.

Adult Demodectic mange can appear as generalised patches of hair loose often with inflammation and itchiness (pruritus). Some dogs have very red inflamed feet/toe lesions which can be mistaken for a contact allergy. occasionally, pimples or pustules are present. Some dogs have a dandruff type of problem in the coat.

Diagnosis

A vet does several deep skin scrapes to collect surface skin samples. On examination with a microscope, the Demodex mites are easily identified.

Demodex eggs & nymph ("Mange" mite)	Demodex larvae	Adult Demodex mite

Treatment

Juvenile cases may go away untreated but its usually a good idea to treat the lesions just in case it becomes generalised.

The dog should be placed on antibiotics to kill any secondary bacterial invaders.

We wash the dogs in Dermcare Pyohex 2-3 times a week to flush out the hair follicles where the mites are living.

Once the Pyohex is rinsed off, dogs over 3 months can be rinsed in a strong Demodex rinse, closely following all the safety directions as it can can nausea and illness in humans if contact is made with the solution.

Generalised adult cases need to be treated more aggressively.

They also need antibiotics and Pyohex shampoo and rinsing with a very strong anti- mange mite solution.

If not desexed, they must be ASAP. There appears to be a correlation between the presence of sex hormones and persistence of the mite in these cases.

Skin scrapes are repeated at regular intervals to monitor progress.

Once there have been 2 "mite free" skin scapes 2 weeks apart, therapy is ceased.

Cases not responding to the above therapy are sometimes placed on Ivermectin. However, this is an off-licence use of the product, and as such, the vet can not be held responsible should any untoward side effects occur. We start off with very low doses gradually building it up to check for early symptoms of incompatibility.