What You Should Know About Demodex Mites

Some Demodex Mites Live On Human Hosts

People normally have two types of these mites: Demodex folliculorum and Demodex brevis. They are sometimes called eyelash mites. Demodex mites are a natural part of the human microbiome or body ecology. They are believed to serve a useful function in removing waste by feeding off dead skin cells on the face and elsewhere. However, larger than normal concentrations of Demodex mites on the face are associated with flare-ups of rosacea. Rest assured that only in rare conditions do humans get affected by the type of Demodex mites that lives on a dog.

Demodex Mites in Dogs

Different animals are hosts to different species of Demodex mites. The species that lives on dogs is called Demodex canis. Normally, the numbers of demodex mites living on a dog cause no problems, but if their numbers increase drastically, they can cause a skin condition called demodectic mange.

Demodectic mange is referred to clinically as “demodicosis.” It’s also called “red mange,” because of the reddening of the skin that occurs, and sometimes just called “demodex.”

The dog will typically lose hair in patches, and if limited to isolated patches, it’s referred to as localized demodectic mange. If the condition is left untreated, the mange can spread to many areas of the dog’s skin, becoming a more severe condition called generalized demodectic mange. Generalized demodectic mange will show as larger areas of skin or a dog’s entire body losing hair, and also be accompanied by overall itchiness and smelly skin caused by secondary bacterial infections that set in.

How Does a Dog Get Demodex Mites?

Because demodex mites live deep inside the dermis (skin) and most dogs have some of them, the mites usually transfer between dogs only with prolonged direct contact, such as when mother dogs are nursing their puppies. As a result, lesions from demodex mange will show up in puppies on the muzzle, face, forelimbs, and around the young dog’s eyes. Symptoms do not usually show up in puppies until they are between 3 and 6 months old. The mother may not show any signs of having demodex mites but still can transmit them to her puppies, which do not yet have full-grown immune responses. Because its immune system does not mature until it’s 12 to 18 months old, a dog with demodectic mange may have relapses until it’s halfway into its second year of life. It is important to treat signs of demodex mites as soon as a relapse occurs to minimize the possibility of developing uncontrollable problems.

Demodex Mange Tendencies by Breed

There have been more frequent observations of demodectic mange in certain breeds, such as Dalmatians, American Bulldogs and American Pit Bull Terriers. In addition, Old English Sheepdogs and Shar Peis are prone to demodectic mange infections on their feet.

Appearance of Demodex Mange

Demodex mange can manifest as sores or lesions of two types:

• squamous, which causes dryness, hair loss, and thickening of the skin, and
• pustular, which is the more severe form, causing secondary staph infection which causes the skin to have a red and wrinkled appearance.

In early stages and in young dogs, demodex mite problems may be confined to localized spots, giving the dog a polka dot appearance, or the mites can create generalized mange, in which the dog will lose hair all over, be itchy and smelly. Demodex mites can cause itchy hot spots to occur when the dog licks or scratches at areas that are aggravated and have secondary infections.

Adult-onset Demodex Mange

Adult-onset demodicosis is a mite condition usually seen full grown dogs that otherwise appear healthy but that are actually affected with some immunity disorder. For this reason, treating the mites can be done at home but if the mite condition proves difficult to cure, a veterinarian should be consulted and give a full health assessment of the dog’s overall immune system. A veterinarian can screen against conditions such as hypothyroidism, heartworm, cancer, adrenal gland dysfunction, Cushing’s disease, and other pervasive, immunity-compromising problems. In some dogs, owners may have previously been advised to treat their dog with prescription cortisone medications to control mites or other conditions. These cortisone treatments can allow otherwise harmless colonies of mites to rapidly reproduce and cause skin disease.

How is Demodectic Mange Treated?

Topical Treatments

When caught in time, demodectic mange can be treated with topically or directly on the skin where it shows. Many of the products can be acquired easily over the counter, prior to a trip to the vet, and they range in degrees of effectiveness, price and method of use. Some are shampoos and others are topical sprays for either the dog or its environment. Formulations vary widely. For the itchy hot spots and irritated skin that can come with mange, EcoSpot is a no-rinse botanical spray that soothes and cleanses the skin.

Dips

Dips are stronger, more aggressive topical treatments. It’s often advised to clip and bathe the dog first with shampoo containing benzoyl peroxide to help remove oils and skin debris. Dip for demodectic mange commonly contain an insecticide called amitraz. This is a very strong insecticide that must be used with caution. Amitraz can cause side effects to both humans and dogs, and rubber gloves should be worn when using them. Signs of improper use on a dog include vomiting, nausea, and lethargy for as much as 36 hours after use. Toy breeds can be especially susceptible to side effects of amitraz and very dilute concentrations must be used. Some dogs do not respond to this type of treatment on the first attempt and repeated applications over several weeks can be required, and because of its toxicity, the concentration should be increasingly diluted.

Oral Prescription Drug Treatments

There are several drugs that can be prescribed by veterinarians to treat demodectic mange. Drugs approved for heartworm prevention in dogs and cats can be prescribed, such as the class of drugs called ivermectins. Ivermectins used to treat parasites on cattle may also be prescribed for oral use in dogs to treat demodectic mange, however it has severe side-effects, including death. It should definitely be avoided in herding breeds, such as Collies, Shetland Sheepdogs, Australian Shepherds, Old English sheepdogs. Also, since dogs that have generalized demodictic mange frequently have underlying skin infections, antibiotics may be prescribed for the first several weeks of treatment.

Now for Some Good News About Demodex Mites

Demodex mite infestations are generally less severe than infestations of Sarcoptic mites (also known as scabies). Usually once they are treated, most dogs do not get re-infested, as the dog develops improved immune defenses against demodex mites. (Certain dogs however have a genetic make-up that lacks of adequate immune defense against the mites.) When treated early, demodex mites don’t have to spread.

Soothing Relief for Hot Spots and Irritated Skin

Demodex problems often come with itchy hot spots and irritated skin that your dog keeps licking and chewing. EcoSpot is a no-rinse botanical spray that soothes and cleanses hot spots and red, raw, irritated skin, made with witch hazel, organic calendula, burdock root and organic mullein leaf extracts. It is not a mite treatment; it soothes the skin while you deal with the cause.

• Improvement you can see in as little as 2-3 days
• Part the fur and spray: no rubbing, no rinsing
• No antibiotics, no steroids, no artificial preservatives
• 365-day returns

Order EcoSpot Hot Spot Spray – 4 fl oz

Free shipping on orders over $35, otherwise $2.99. Ships within 1 business day.

If you see patchy hair loss or red, scaly skin, act early: localized demodectic mange is easier to manage than generalized mange. For the itchy hot spots along the way, keep EcoSpot on hand. Orders ship within 1 business day.

Further Reading

• "Demodex Mites in Dogs," The Skin Vet
• "Demodex (Dog Mites) Signs, Symptoms, And Treatment Options," Upstate Veterinary Specialties
• "Canine Demodectic Mange," Mar Vista Animal Medical Center