THE PET HEALTH LIBRARY By Wendy C. Brooks, DVM, DipABVP Educational Director, VeterinaryPartner.com

Demodectic mange mites live in the hair follicles of all species as normal skin residents. They live in balance with their host's immune system but if the balance shifts in favor of the mite, an itchy, scaly skin disease results.

Demodectic mange in dogs is extremely common, especially in puppies. Demodicosis in cats is much more unusual and this article will feature the differences.

Two Types of Demodex Mites Are in Cats

Demodex cati and Demodex gatoi are the two demodex mites of cats. (Dogs only have Demodex canis to address.) Demodex cati is long and slender like the "alligator-esque" canine mite and lives inside hair follicles, also like the canine mite, while Demodex gatoi is short, stubby with hardly has any tail at all, and lives more superficially in the skin.

Demodex cati

Demodex gatoi

Because this is not a common condition, only a limited number of cases have been published and much extrapolation from the canine condition is necessary. Some sort of immune suppression appears to be a pre-requisite to infection for both mites (as is the case with dogs). Unlike the canine situation, there is some reason to think that Demodex gatoi may be transmissible between individuals. Demodex gatoi infection appears to be slightly more common that infection with Demodex cati.

Diagnosis

A skin scraping is necessary to detect these mites, though they are not as easily seen nor present in the obvious large numbers as are the canine mites. The fact that this condition is so rare (and thus unexpected) is probably the chief impediment to making the diagnosis.

Treatment

Fortunately, after the diagnosis is made, treatment is not difficult. Lime sulfur dips are smelly but effective when given every 5 to 7 days for six dips, though one should not discontinue dipping until skin scrapes are negative.

Date Published: 4/14/2003 11:01:00 AM