It is thought that up to 10% of normal dogs carry demodex without showing any signs. Spread is directly from the female dog to her pups. Hair loss and scratching around the face and front legs are the early signs. Secondary bacterial infections are common. Spread over the rest of the body is generally only seen in dogs with an immune deficiency. This is also true for older dogs which develop clinical demodex.

Diagnosis is via microscopic examination of skin scrapings.

Treatment requires twice weekly rinsing with the insecticide Amitraz. Ivermectin has been found to be a useful aid in treating more severe cases however it is rarely effective as a sole treatment. Secondary bacterial infection must also be treated with antibiotics.

The outlook for normal dogs is good however failure to respond suggests immune deficiency and carries a poor prognosis (outlook) for cure.