Cheyletiellosis is a mild
dermatitis caused by the Cheyletiella species of mites. It is also known
as walking dandruff. Cheyletiella are large mites that live on the skin
surface of dogs, cats,
rabbits, and humans. 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 highly contagious. Transmission is by direct contact with
an affected animal. Symptoms in animals very from no signs to intense itching,
scales on the skin, and hair loss. 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 is by finding the mites or eggs microscopically in a skin scraping
or a combing. 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. In unresponsive cases, ivermectin is used.
Cheyletiella yasguri - infests dogs
Cheyletiella blakei - infests cats
Cheyletiella parasitivorax - infests rabbits
Each of these species can affect humans.
Griffin, Craig E.; Miller, William H.; Scott, Danny W.(2001). Small Animal
Dermatology (6th ed.). W.B. Saunders Company.