Demodex Mites Demodectic Mange

Mite Problem / Saturday, March 3rd, 2018

A wide range of pets can be infected with Demodex and Demodectic mange mites. These pets can be dogs, cats, ferrets, rabbits and other domestic and farm animals. Demodectic mange also called demodicosis or Red Mange is caused by sensitivity to an overpopulation of Demodex canis as the animal’s immune system is unable to keep the mites under control. Demodex is a mite that occurs naturally around 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.

In some animals especially those with a weak or impaired immune system or animals with an intense stress, or malnutrition, the mites can reproduce rapidly. The rapid growth in the number of mites causes symptoms in sensitive dogs that range from mild irritation and hair loss on a small patch of skin to severe and widespread inflammation with open sores and pustules forming on the skin. In most cases with only 4 or less patches of mite infestation localized Demodex will correct itself as the immune system improves.

Minor cases of demodectic mange usually do not cause much itching but might cause open sores or pustules on the dog’s skin, redness, scaling, hair loss, 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.

In the more severe form, hair loss can occur in patches all over the body and might be accompanied by crusting, pain, enlarged lymph nodes, and deep skin infections.


For Demodectic mange is similar to other forms using skin scrapings but since some presence of Demodectic mites are normal it is more a counting of how many mites are found and does not conclusively show the dog is suffering from Demodex Mange. What the vet would consider abnormally high numbers of the mite are more useful.

In breeds such as the West Highland White Terrier, relatively minor skin irritation which would otherwise be considered allergy should be carefully scraped because of the predilection of these dogs to demodectic mange. Skin scrapings may be used to follow the progress of treatment in demodectic mange.

Some breeds appear to have an increased risk of mild cases as young dogs, including the Afghan hound, American Staffordshire terrier, Boston terrier, Boxer, Chihuahua, Shar Pei, Collie, Dalmatian, Doberman pinscher, Bulldog, English Bull Terrier, Miniature Bull Terrier, German Shepherd Dog, Great Dane, Old English sheepdog, American Pit Bull Terrier, West Highland White Terrier, Rat Terrier, and Pug.

Demodectic mange also occurs in other domestic and wild animals. The mites are specific to their hosts, and each mammal species is host to one or two unique species of Demodex mites. There are two types of demodectic mange in cats. Demodex cati causes follicular mange, similar to that seen in dogs, though it is much less common. Demodex gatoi is a more superficial form of mange, causes an itchy skin condition, and is contagious amongst cats.


Localized demodectic mange is considered a common puppyhood ailment, with roughly 90% of cases resolving on their own with no treatment. Minor, localized cases are often treated with medicated shampoos and not treated with agents aimed at killing mites as these infestations often resolve within several weeks in young dogs.

Demodectic mange with secondary infection is treated with antibiotics and medicated shampoos as well as parricidal agents.

Many insecticides will treat Mites infestations relatively effectively but the safety of using them has been questioned often.

Permethrin is perhaps the most commonly prescribed insecticide and when used in a lotion is known to have unpleasant side effects including itching and burning. Of greater concern is the fact that this is a synthetic form of the chemical, Pyrethrum, a pesticide with suspected cancer causing properties.

Lindane, another chemical pesticide that is still used in many countries despite that it has now been banned in over 40 countries for possible associations with leukemia, seizures and Non-Hodgkin’s Lymphoma.

Malathion is another harsh chemical insecticide. Malathion has evidence to suggest that it can cause breathing difficulties.

Amitraz is a parricidal rinse that is licensed for use in many countries 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 Ivermectin, 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.

Some of the other drug categories include those based on Avermectin. Other drugs in the same family include Doramectin and Milbemycin.

Selamectin is a licensed chemical prescription Licensed in several countries which is applied as a drip-on medication directly to the skin.

Ivermectin is a medication given by mouth for two to four weekly treatments. Ivermectin is not safe to use on collies-and other herding dogs.

Cats with Demodex gatoi can be treated with weekly or bi-weekly sulfurated lime rinses. Demodex cati are treated similarly to canine demodicosis.

The immune system is compromised in most cases of severe mite infestation. In order to make the infestation go away faster some dietary changes may need to be made. Improvements in diet will not necessarily kill scabies off completely as the immune system recovers. Diet changes and the addition of certain foods and vitamins will undoubtedly help.

There are some foods and supplements that will boost and support the immune system. Other foods like garlic are well-known for their anti-parasitic properties and can be taken in either supplements or through the diet.

Some supplements which can assist the immune system to fight the infestation include Vitamin A, Primrose Oil, Zinc and Vitamin E.

What can happen in schools and dormitories? There is also a movie about clothing infected with scabies by employees in the movies section.

Johnstown school nurse Sunny Humphrey is seeking parents’ assistance in an effort to fight a recurrence of scabies at Oregon Elementary.

Humphrey told The Independent that spots are back on some of the same students in the first-grade class that dealt with an outbreak in early March.

“We are assuming resurgence,” she said. “It isn’t like there are new cases. We’re researching it and redoubling our efforts.”

Scabies are tiny mites that burrow under the skin and produce intense itching and red bumps that usually look like insect bites. The mites are attracted to the warmth of humans, especially to areas like the underarms and between the fingers.

The bumps often don’t appear until four to six weeks after the infestation, Humphrey said. Scabies are spread by skin-to-skin contact.

The district needs parents’ help in being alert to the symptoms and taking their children for treatment, if they show signs of scabies.

“Don’t just consider it a mosquito or flea bite,”Humphrey said. “We need the parents help in communicating with us. We’re doing all we can do. I appreciate the parents who’re offering suggestions. I’m open to listening to suggestions.”

She said six cases of scabies were originally confirmed, including the first-grade teacher.

“Naturally we’re on high alert,” Humphrey said. “So far, it’s contained to that classroom.”

The district hired an expert nurse for most of last week to help with the effort, according to Humphrey.

“We’re putting an extra person on it, making sure children are getting clothes in a bag,” she said. “It’s taking a lot of time to fight this for me. There are still 1,500 other kids in the district too. We’ve been successful in containing it so far, so good. I hope we’ve got it.”

Following the advice of the Licking County Health Department, the first-grade classroom has been cleaned and inspected and the students are now keeping their coats and book bags in individual plastic bags during school hours.

The LCHD also recommended the school clean any upholstered furniture and rugs, as well as any plush toys or other items in the affected classroom.

The Centers for Disease Control (CDC) and Prevention indicate that children and adults can return to school or work 24 hours after being properly treated.

In addition, the CDC recommends that bedding and clothing of those individuals who are infested with scabies be washed in hot water and dried on the hot cycle in order to assist with controlling the infestation.