Cheyletiella Dermatitis
The disease caused by Cheyletiella mites is often called "walking dandruff". On close observation of an infested dog, cat, or rabbit, it may be possible to see movement of the dandruff on the skin. The movement is caused by the mites motoring around under the scales. Cheyletiella mites are found on animals throughout the United States. They generally do not cause significant disease.
What is the life cycle of Cheyletiella mites and how are
they transmitted?
The details of the life cycle of Cheyletiella mites are not known,
but presumably the life cycle is completed on one host.
The adult mite is transmitted by direct contact between animals. The mites can live several days while off the host, so it is possible for animals to become infected through environmental contamination, e.g., bedding.
What are the symptoms of walking dandruff?
The mites cause skin irritation, usually along the back of the
animal. Infested animals may have slight hair loss, scales (dandruff),
itching and possibly some thickening of the skin. Cats and rabbits
may not show any signs of infestation.
How is an infestation with Cheylettiella diagnosed?
Mites may be seen on the animal, especially if you use a magnifying
glass. Examining dandruff, hairs or scrapings of the skin under
the microscope can positively identify the mites. Because cats
groom a lot, Cheyletiella infestations can sometimes be diagnosed
in them by examining their feces. (The animals swallow the mites
which then go through the intestines without being digested.)
What is the treatment for an infestation with Cheyletiella?
Cheyletiella are killed by most of the common insecticides used
against fleas including pyrethrins, permethrins and organophosphates.
Be sure to use an insecticide approved for your species of pet.
Rabbits and cats should NOT be treated with permethrin. In general,
insecticides safe for cats are also safe for rabbits. Dips in
lime sulfur and injections of ivermectin have also been used to
treat an infestation with these mites.
The mite can live for several days off the host, so the environment needs to be cleared of mites as well. At the same time the animals are treated, the environment may be fogged or sprayed. Since the mites only live for several days off the host, it is often effective to remove the rabbit, dog or cat from the premises for several days until the mites die. This would prevent reinfestation.
Could I get Cheyletiella from my pet?
These mites can temporarily infest humans causing a mild skin
irritation and some itching. In severe cases some open lesions
may occur.
The information on this page was obtained from the site www.peteducation.com