''Demodex brevis'' is one of the two species of face mite that inhabit humans (the other being '' Demodex folliculorum''). They are very similar to ''Demodex folliculorum'', with just a few differences. They are usually found in the

sebaceous gland A sebaceous gland is a microscopic exocrine gland in the skin that opens into a hair follicle to secrete an oily or waxy matter, called sebum, which lubricates the hair and skin of mammals. In humans, sebaceous glands occur in the greatest numb ...

s of the human body. The same way that ''D. folliculorum'' reproduces in the follicles, ''D. brevis'' reproduces in the sebaceous glands. Under normal conditions they are not harmful, and are considered to be commensals (the mite benefits but there is no harm or benefit to the host) rather than

parasites Parasitism is a close relationship between species, where one organism, the parasite, lives on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The entomologist E. O. Wilson ha ...

(where the host is harmed) or mutualistic organisms (where the host is benefitted). During a severe infestation, though, there may be adverse effects on the host, such as

demodicosis Demodicosis , also called Demodex folliculitis in humans and demodectic mange () or red mange in animals, is caused by a sensitivity to and overpopulation of '' Demodex spp.'' as the host's immune system is unable to keep the mites under control. ...

References

Trombidiformes Animals described in 1963 Parasitic_arthropods_of_humans {{Trombidiformes-stub