Can Demodex Folliculorum Live on a Dog's Skin?

When it comes to bacteria, viruses and parasites, many have the ability to spread from species to species, such as dog to human. When these infectious agents, or bugs, have this ability, they are considered zoonotic. Demodex mites are microscopic, eight-legged creatures that routinely reside on your skin, as well as your dog’s skin. Demodex mites, however, are not zoonotic and Demodex folliculorum, the mites that live on humans, will not reside on your dog.

Humans typically have two species of Demodex mites that live on skin. Demodex folliculorum and Demodex brevis. They burrow into hair follicles and commonly reside in the eyelids, nose, cheeks, forehead and chin. They prefer moist and oily skin and, for this reason, avoid areas of dry skin. Other areas mites may reside other than the face include the ear canal, groin and underarms. They feed off the sebum, or natural skin oil.

Demodex mites have been linked to outbreaks of rosacea in humans. Patients with rosacea show higher mite populations than those without the condition. Researchers believe that when the mites die, a bacteria releases, causing the symptoms seen with rosacea. Symptoms of rosacea include facial redness, bumps or pimples on the skin’s surface, enlarged blood vessels, stinging or burning of the skin and a thickening of the skin around the nose.

Demodex canis, Demodex inaji and Demodex sp. cornei are the three Demodex species that can live on your dog’s skin. Just as they are considered normal skin fauna in humans, these mites live and burrow in the skin and hair follicles on dogs. In most cases, the mites do not cause any problems to your dog. However, in dogs with compromised immune systems, the mite population can grow out of control, resulting in demodicosis, or Demodex mange.

When canine mite populations grow and your dog’s immune system is unable to control them, symptoms of mange may surface. Symptoms include small skin lesions, thinning hair or areas of hair loss, severe itchiness, skin inflammation, lethargy, loss of appetite and secondary skin infections. These symptoms may affect the entire body or be localized to a specific area. Treatment for Demodex mange typically includes topical ointments, shampoos and dips.