Signs develop approximately 2-6 weeks after exposure to a carrier. Pets that go outside may brush against a tree or plant that a wild carrier contacted. Other sources are pets that are boarded, go to day care facilities, dog parks, groomed, or exposure at an animal hospital. Humans that come in close contact with an affected dog may develop an itchy rash on their arms, chest, or abdomen. Human lesions are usually transient and should resolve spontaneously after the affected dogs have been treated.
Clinical signs show a pet that is intensely itchy.
Skin lesions include ear margin scaling, lesions around the eyes, and trunk of the body. There is poor response to anti-inflammatory drugs. Differential diagnosis included, flea allergic dermatitis, food allergy, contact dermatitis, demodecosis, yeast infection, and primary skin infection. Diagnosis is made by identification of the mite on skin scraping. False negative scrapings are common as the mite is difficult to find on skin scraping.