Parasites Part 9: Cheyletiella

Cheyletiella are mites that affect dogs, cats, and rabbits.  There are separate species but host specificity is controversial.  Cheyletiella are relatively uncommon.  They are large mites that are light in color and cause large amounts of scaling which earns them the nickname of "walking dandruff."

In addition to scaling, Cheyletiella also cause itching and hair loss.  Transmission is usually from direct contact but also from infected environments.  Adults can live off a host for 10-14 days.  Diagnosis can be made by microscopic examination of hairs, skin scrapings, and scotch tape preps (placing tape over the scale and debris on the fur and then placing the tape on a slide to look at under the microscope).  They are most common in crowded and unsanitary conditions.

Cheyletiella are susceptible to many common topical insecticides and antiparasitic shampoos.  Protocols are similar to those used on lice.  Treatment of all in-contact animals and the environment (bedding, etc) is also recommended.

Zoonotic Potential
Cheyletiella will cause a transient rash on humans but it typically resolved on it's own after the pets have been treated.