Demodicosis
Guides
Demodex
Mammalian Follicle Mites, Eyelash Mites, Face Mites
Demodex is a genus of microscopic mites that inhabit hair follicles and sebaceous glands of mammals. Approximately 65 species are known, with two species—D. folliculorum and D. brevis—occurring on humans. These mites are typically commensal, causing no symptoms in healthy hosts, but can proliferate and cause skin conditions when host immunity is compromised. The genus exhibits strong host specificity, with mite lineages tracking host ancestry across generations.
Demodex canis
dog follicle mite
Demodex canis is a microscopic follicular mite that inhabits the skin of domestic dogs as a commensal organism, living primarily in hair follicles and sebaceous glands of the facial region. Under normal conditions, it occurs in small numbers and feeds on cellular debris and sebum without causing symptoms. However, when host immune function is compromised or mite populations proliferate excessively, the mite becomes pathogenic, causing demodicosis—a non-contagious inflammatory skin disease characterized by alopecia, erythema, and secondary infections. The mite exhibits increased activity during evening hours and has been observed to regulate host cholinergic immunosuppressive pathways, potentially facilitating its own proliferation. Three Demodex species (D. canis, D. injai, and D. cornei) can cause canine demodicosis, with D. canis being the most common.