Issue Description Is a mild dermatitis caused by mites of the
genus Cheyletiella. It is also known as walking dandruff due to skin
scales being carried by the mites. Cheyletiella live on the skin
surface of dogs, cats, rabbits, and humans. The adult mites are about
0.385 millimeters long, have eight legs that have combs instead of
claws, and have palpi that end in prominent hooks. They do not burrow
into the skin but live in the keratin level. Their entire 21 day life
cycle is on one host. They cannot survive off the host for more than
10 days. Cheyletiellosis is seen more commonly in areas where fleas
are less prevalent, because of the decreased use of flea products that
are also efficacious for the treatment of this mite.
Symptoms Cheyletiellosis is highly contagious.
Transmission is by direct contact with an affected animal. Symptoms in
animals vary from no signs to intense itching, scales on the skin, and
hair loss. The lesions are usually on the dorsum of the animal.
Symptoms in humans include multiple red, itchy bumps on the arms,
trunk, and buttocks. Because humans are an irregular host for the
mite, the symptoms usually go away in about three weeks.
Diagnosis Diagnosis is by finding the mites or eggs
microscopically in a skin scraping, combing, or on acetate tape
applied to the skin.
Treatment The most common treatment in animals is weekly
use of some form of topical pesticide appropriate for the affected
animal, often an anti-flea product. Fipronil works well, especially in
cats. In unresponsive cases, ivermectin is used, Selamectin is also
recommended for treatment. None of these products are approved for
treatment of cheyletiellosis. Other pets in the same household should
also be treated, and the house or kennel must be treated with an
environmental flea spray.