Ear mites are mites that live in the ears of animals and humans. The most commonly seen species in veterinary medicine is "Otodectes cynotis" (Gk. oto=ear, dectes=biter, cynotis=of the dog). This species, despite its name, is also responsible for 90% of ear mite infections in cats.

In veterinary practice, ear mite infections in dogs and cats may present as a disease that causes intense itching in one or both ears, which in turn triggers scratching at the affected ear. An unusually dark colored ear wax (cerumen) may also be produced. Cats, as well as dogs with erect ears that have control over ear direction, may be seen with one or both ear pinnas held at an odd or flattened angle.

The most common lesion associated with ear mites is an open or crusted ("scabbed") skin wound at the back or base of the ear, caused by abrasion of the skin by hind limb claws, as the ear has been scratched in an attempt to relieve the itching. This lesion often becomes secondarily infected and crusted from ordinary skin bacteria, so that the common presentation of ear mites is such a wound appearing on the back or base of one or both ears. This is accompanied by the Pinnal-Pedal Reflex that appears as reflex scratching motions of the hind limb when the ear is manipulated (this test is positive as well in other mite infections of the outside and rim of the ear pinnas in mange). When the ear mite infection is treated, such wounds resolve spontaneously, and this resolution may be speeded with application of topical antibiotics.

The most common ear mite (as well as mange mite) treatments currently use the antiparasitics ivermectin and selamectin, usually as topical preparations. Ivermectin is available as a direct water-based liquid that is squeezed into the ear canal and massaged at the base of the ear to distribute the medication. Selamectin is available as a once-a-month preparation that can be applied to the animal's skin, which prevents mite infestation over that time.

The rabbit ear mite, "Psoroptes cuniculi", is larger than "Otodectes cynotis". It causes thick firm debris to form in the ear canal, and can eventually migrate to the skin of the outer ear and face. Symptoms include scratching and shaking of the head. Treatment includes topical selamectin, or injections of ivermectin and frequent cleanings of the rabbit's environment.

Scaly foot causes lesions of the skin with dermatitis and thickening of the skin.

Commonly known as scaly face, scaly legs, or tassel foot, knemidocoptiasis affects primarily the face and legs of birds around the world worldwide and can be fatal.

The characteristic symptoms of a scabies infection include intense itching and superficial burrows. The burrow tracks are often linear, to the point that a neat "line" of four or more closely placed and equally developed mosquito-like "bites" is almost diagnostic of the disease. Because the host develops the symptoms as a reaction to the mites' presence over time, typically a delay of four to six weeks occurs between the onset of infestation and the onset of itching. Similarly, symptoms often persist for one to several weeks after successful eradication of the mites. As noted, those re-exposed to scabies after successful treatment may exhibit symptoms of the new infestation in a much shorter period—as little as one to four days.

In the classic scenario, the itch is made worse by warmth, and is usually experienced as being worse at night, possibly because distractions are fewer. As a symptom, it is less common in the elderly.

Mange is a class of skin diseases caused by parasitic mites. Since mites also infect plants, birds, and reptiles, the term "mange", suggesting poor condition of the hairy coat due to the infection, is sometimes reserved only for pathological mite-infestation of nonhuman mammals. Thus, mange includes mite-associated skin disease in domestic animals (cats and dogs), in livestock (such as sheep scab), and in wild animals (for example, coyotes, cougars, and bears). Since mites belong to the arachnid subclass Acari (also called Acarina), another term for mite infestation is acariasis.

Parasitic mites that cause mange in mammals embed themselves either in skin or hair follicles in the animal, depending upon their genus. "Sarcoptes" spp. burrow into skin, while "Demodex" spp. live in follicles.

In humans, these two types of mite infections, which would otherwise be known as "mange" in furry mammals, are instead known respectively as scabies and demodicosis.

Sarcoptic mange, also known as canine scabies, is a highly contagious infestation of "Sarcoptes scabiei canis", a burrowing mite. The canine sarcoptic mite can also infest cats, pigs, horses, sheep, and various other species. The human analog of burrowing mite infection, due to a closely related species, is called scabies (the "seven year itch").

All these burrowing mites are in the family Sarcoptidae. They dig into and through the skin, causing intense itching from an allergic reaction to the mite, and crusting that can quickly become infected. Hair loss and crusting frequently appear first on elbows and ears. Skin damage can occur from the dog's intense scratching and biting. Secondary skin infection is also common. Dogs with chronic sarcoptic mange are often in poor condition, and in both animals and humans, immune suppression from starvation or any other disease causes this type of mange to develop into a highly crusted form in which the burden of mites is far higher than in healthy specimens.

Scaly foot, otherwise known as knemidocoptiasis, is caused by burrowing mites in the genus "Knemidocoptes". The condition can be compared with sarcoptic mange in mammals, but does not seem to cause the same level of itching. The birds chiefly affected are galliformes (chickens and turkeys), passerines (finches, canaries, sparrows, robins, wrens), and psittacine birds (parrots, macaws, parakeets, budgerigars). The condition sometimes additionally affects piciformes (woodpeckers, toucans) and anseriformes ducks, geese, swans), raptors and other birds. The two species of mite most often implicated are "K. jamaicensis" and "K. intermedius". Other related species of mite affect feather follicles and cause depluming. The mites are mostly transmitted by prolonged direct contact, particularly from parent bird to unfledged nestling.

This disease in humans is usually caused by "Demodex folliculorum" (not the same species affecting dogs) and is usually called demodicosis which 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 be a small pustules (pimples or pustules) at the exit of hair, placed on inflamed, congested skin. Demodicosis is accompanied by itching, swelling and erythema of the eyelid margins, the appearance of scales at the base of the eyelashes. Typically, patients complain of eyestrain. Characteristic of view of the affected century: plaque on the edge of the eyelids, eyelashes stuck together, surrounded by crusts as a clutch.

Demodicosis, also called demodectic mange or red mange, is caused by a sensitivity to and overpopulation of "Demodex canis" as the hosts immune system is unable to keep the mites under control.

"Demodex" is a genus of mite in the family Demodicidae. "Demodex canis" occurs naturally in the hair follicles of most dogs in low numbers around the face and other areas of the body. In most dogs, these mites never cause problems. However, in certain situations, such as an underdeveloped or impaired immune system, intense stress, or malnutrition, the mites can reproduce rapidly, causing symptoms in sensitive dogs that range from mild irritation and hair loss on a small patch of skin to severe and widespread inflammation, secondary infection, and in rare cases can be a life-threatening condition. Small patches of demodicosis often correct themselves over time as the dog's immune system matures, although treatment is usually recommended.

Demodex mite bite is a cutaneous condition caused by infestation by "Demodex folliculorum".

Most of the mites which cause this affliction to humans are from the order Acari, hence the name Acariasis. The entire taxonomic classification to order would be:

- Kingdom: Animalia

- Phylum: Arthropoda

- Subphylum: Chelicerata

- Class: Arachnida

- Order: Acari (At the order level, there is still substantial argument among researchers as to how to categorize Acari. Some call it a subclass, others a superorder, "Acarina".)

Specific species involved include:

- Acariformes

- Trombidiformes

- "Trombicula" species (trombiculosis or chiggers)

- "Demodex" species (Demodicosis)

- "Pyemotes tritici"

- "Cheyletiella"

- Sarcoptiformes

- "Sarcoptes scabiei" (Scabies)

- Parasitiformes

- "Dermanyssus gallinae"

- "Liponyssoides sanguineus"

- "Ornithonyssus bacoti", "Ornithonyssus bursa", "Ornithonyssus sylviarum"

- Another candidate is "Androlaelaps casalis". However, based on this mite's life style as a predator on other mite species (such as the previously-mentioned "Dermanyssus gallinae"), it is highly unlikely to be a cause of acariasis.

Some of these reflect reports existing of human infestation by mites previously believed not to prey on humans.

There are several complications with the terminology:

Acariasis is a term for a rash, caused by mites, sometimes with a papillae (pruritic dermatitis), and usually accompanied by severe itching sensations. An example of such an infection is scabies.

The closely related term, mange, is commonly used with domestic animals (pets) and also livestock and wild mammals, whenever hair-loss is involved. "Sarcoptes" and "Demodex" species are involved in mange, but both of these genera are also involved in human skin diseases (by convention only, not called mange). "Sarcoptes" in humans is especially severe symptomatically, and causes the condition scabies noted above.

Another genus of mite which causing itching but rarely causes hair loss because it burrows only at the keratin level, is "Cheyletiella." Various species of this genus of mite also affect a wide variety of mammals, including humans.

Mite infestation sometimes implies an ectoparasitic, cutaneous condition such as dermatitis. However, it is possible for mites to invade the gastrointestinal and urinary tracts.

MeSH uses the term "Mite Infestations" as pertaining to Acariformes. However, mites not in this grouping can be associated with human disease. (See "Classification", below.)

The term Acari refers to ticks and mites together, which can cause ambiguity. (Mites are a paraphyletic grouping).

Mites can be associated with disease in at least three different ways: (1) cutaneous dermatitis, (2) production of allergin, and (3) as a vector for parasitic diseases. The language used to describe mite infestation often does not distinguish among these.

Trombiculosis, trombiculiasis, or trombiculidiasis is a rash caused by trombiculid mites which is often referred to as a chigger bite.

Scaly leg is a disease of chickens and other birds. It is caused by a parasitic mite, "cnemidocoptes mutans". The mite burrows under the scales in the bird's legs, but may also infest other areas, such as the comb or wattles of chickens. The mite spends its entire lifecycle on the birds and is usually spread by direct contact.

Birds infested with scaly leg have raised or protruding scales, sometimes with a white crusty appearance. Scaly leg is irritating to the infected bird, and in extreme cases can result in lameness.

In domestic birds the disease may be treated by application of an oily substance such as petroleum jelly, vegetable oil, or a commercial chest rub, thus preventing the mites breathing. Alternatively an insecticide may be used to kill the mites – or the two methods may be combined. The loose crusty scales may also be removed by soaking the afflicted bird's legs in soapy water mixed with diluted ammonia, and the encrusted areas scrubbed gently with a soft brush. Complete removal may take multiple treatments. Dropped scales may remain infectious for up to a month, and so pen, perches, and nesting areas may also be treated, or birds may be moved to different housing for several weeks.

Wheat warehouse itch is a cutaneous condition caused by a mite, "Cheyletus malaccensis".

A hot spot, or "acute moist dermatitis", is an acutely inflamed and infected area of skin irritation created and made worse by a dog licking and biting at itself. A hot spot can manifest and spread rapidly in a matter of hours as secondary Staphylococcus infection causes the top layers of the skin to break down and as pus becomes trapped in the hair. Hot spots can be treated with corticosteroid medications and oral as well as topical antibiotic application, as well as clipping hair from around the lesion. Underlying inciting causes include flea allergy dermatitis, ear disease or other allergic skin diseases. Dogs with thick undercoat are most subject to getting hot spots.

The most common finding on ear examination is the presence of greyish white thick debris and heaviness in the ear.

Dyshidrosis has been described as having the following characteristics:

- Itchiness of the palms or soles, followed the a sudden development of intensely itchy small blisters on the sides of the fingers, the palms or the feet.

- These blisters are often described as having a "tapioca pudding" appearance.

- After a few weeks, the small blisters eventually disappear as the top layer of skin falls off.

- These eruptions do not occur elsewhere on the body.

- The eruptions may be symmetrical.

Skin disorders are among the most common health problems in dogs, and have many causes. The condition of a dog's skin and coat are also an important indicator of its general health. Skin disorders of dogs vary from acute, self-limiting problems to chronic or long-lasting problems requiring life-time treatment. Skin disorders may be primary or secondary (due to scratching, itch) in nature, making diagnosis complicated.

Otomycosis is a fungal ear infection, a superficial mycotic infection of the outer ear canal. It is more common in the tropical countries. The infection may be either subacute or acute and is characterized by malodorous discharge, inflammation, pruritus, scaling, and severe discomfort. Suppuration can occur due to superimposed bacterial infection commonly due to pseudomonas species and proteus species. The mycosis results in inflammation, superficial epithelial exfoliation, masses of debris containing hyphae, suppuration, and pain.

Eosinophilic folliculitis (also known as "Eosinophilic pustular folliculitis" and "Sterile eosinophilic pustulosis") is an itchy rash with an unknown cause that is most common among individuals with HIV, though it can occur in HIV-negative individuals where it is known by the eponym Ofuji disease. EF consists of itchy red bumps (papules) centered on hair follicles and typically found on the upper body, sparing the abdomen and legs. The name eosinophilic folliculitis refers to the predominant immune cells associated with the disease (eosinophils) and the involvement of the hair follicles.

Symptoms of an allergic reaction to animals may include itchy skin, nasal congestion, itchy nose, sneezing, chronic sore throat or itchy throat, swollen, red, itchy, and watery eyes, coughing, asthma, or rash on the face or chest.

In medicine, animal allergy is hypersensitivity to certain substances produced by animals, such as the proteins in animal hair and saliva. It is a common type of allergy.

Copra itch is a skin condition that occurs on persons handling copra who are subject to "Tyrophagus longior" mite bites.