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 hosts immune system is unable to keep the mites under control. Demodex is a genus of mite in the family Demodecidae. The mites are specific to their hosts, and each mammal species is host to one or two unique species of Demodex mites. Therefore, demodicosis cannot be transferred across species and has no zoonotic potential. Signs and symptoms
Humans
Demodicosis in humans is usually caused by Demodex folliculorum and may have a rosacea-like appearance. Common symptoms include hair loss, itching, and inflammation. An association with pityriasis folliculorum has also been described.Demodicosis is most often seen in folliculitis (inflammation of the hair follicles of the skin). Depending on the location, it may result in small pustules (pimples) at the base of a hair shaft on inflamed, congested skin. Demodicosis may also cause itching, swelling, and erythema of the eyelid margins. Scales at the base of the eyelashes may develop. Typically, patients complain of eyestrain. Dogs
Minor cases of demodectic mange usually do not cause much itching but might cause pustules, redness, scaling, leathery skin, hair loss, skin that is warm to the touch, or any combination of these. It most commonly appears first on the face, around the eyes, or at the corners of the mouth, and on the forelimbs and paws. It may be misdiagnosed as a "hot spot" or other skin ailment.
If treatment is deemed necessary, Goodwinol, a rotenone-based insecticide ointment, is often prescribed, but it can be irritating to the skin. Demodectic mange with secondary infection is treated with antibiotics and medicated shampoos. For more severe generalized cases, Amitraz is a parasiticidal dip that is licensed for use in many countries (the only FDA approved treatment in the USA) for treating canine demodicosis. It is applied weekly or biweekly for several weeks, until no mites can be detected by skin scrapings. Demodectic mange in dogs can also be managed with avermectins, although there are few countries which license these drugs, which are given by mouth daily, for this use. Ivermectin is used most frequently; collie-like herding breeds often do not tolerate this drug due to a defect in the blood–brain barrier, though not all of them have this defect. Other avermectin drugs that can be used include doramectin and milbemycin. Recent results suggest that the isoxazolines afoxolaner and fluralaner, given orally, are effective in treating dogs with generalized demodicosis. Because of the possibility of the immune deficiency being an inherited trait, many veterinarians believe that all puppies with generalized demodex should be spayed or neutered and not reproduce. Females with generalized demodex should be spayed because the stress of the estrus cycle will often bring on a fresh wave of clinical signs. Cats
Cats with Demodex gatoi must be treated with weekly or bi-weekly sulfurated lime rinses. Demodex cati are treated similarly to canine demodicosis.