Healthy Dog: Demodex Mange
First things first, mange is a nasty disease. That being said there are some graphic pictures in this article. There are two kinds of mange that affect dogs: scaroptic and demodex. Both forms of mange are caused by mites living around the skin of the dog. With scaroptic mange the mites live just under the surface of the dog's skin. While the mites associated with demodex live in the hair follicles themselves. Of the two demodex is more commonly seen.
On a healthy dog with a fully functioning immune system a few demodex mites will not cause any problems. However, if a dog has a compromised immune system or an immune system that is immature it will be susceptible to the mites. Interestingly enough most puppies get the mites from their mother in their first days of life. Demodex mange is not contagious to other dogs or people.
The good news is there is a cure for demodex mange. The bad news is that the treatment process is long and can get rather expensive.
The Types of Demodex Mange
Demodex mange can be further broken down into two categories: localized and generalized. Localized demodex typically occurs in puppies, or dogs under a year of age. The hallmarks of localized demodex are; thinning fur around the mouth and eyes and small patches of hair loss. It is important to note that if more than five patches are present at one time it is possible that the disease is progressing to the generalized form. It is not unheard of for localized mange to clear up on its own, reappear in a few weeks, and then clear up again.
Generalized mange is more widespread than localized mange. Dogs with generalized mange typically start with patches of hair loss that progresses to large areas of hair loss. The fur is not able to grow back as the follicles are completely filled with mites and and dead skin. The skin of the dog is extremely delicate and often covered in crust. It is even possible that there may be open sores on the skin and pockets of infection under the skin. There have been some cases there young dogs, one year or younger, have developed generalized demodex mange and it cleared up on its own. However, this should not be expected with all cases.
Thankfully there are treatments available for both forms of demodex mange.
So, how exactly is demodex mange diagnosed? As an average run-of-the-mill pet owner chances are pretty good that you will not be able to tell the difference between scaroptic and demodex mange. All you are going to see is that your dog is losing fur, covered in scaly skin, and has open sores. Your veterinarian will do a skin scraping to determine the exact cause of fur loss. Essentially your vet is going to gently scrap the dog's skin at different locations throughout the body. They will then create a slide and check for mites under a microscope. In the case of demodex mange typically a large number of mites are present on the slide. The skin scraping will then be completed several times throughout the treatment process to insure that the treatment is working.
There is one other method used to determine if mange is effecting the dog. The pedal-pinnal reflex is tested by the examiner lightly touching the ear of the dog. If the dog has mites in its skin or ears the dog will move its foot in a scratching motion. However, this test doesn't definitely test for mange as it also will be positive for ear mites, and it cannot determine which type of mite is causing the mange.
If your vet recommended it would you use ivermectin to treat your dog for demodex mange?
Veterinary medicine has come a long way in the last few years. Just a few decades ago dogs with generalized demodex mange were considered untreatable. While it is true that some dogs have spontaneously healed from both localized and generalized mange it should not be expected. The best thing that can be done for a dog with either form of demodex is for them to be seen by a veterinarian and for the veterinarian to set up a treatment plan for the dog.
Localized demodex mange can be treated with topical medications. Most often the same cleaning solution used on ear mites or a get containing benzol peroxide is used. Often the veterinarian prescribes these drugs and instructs them to be rubbed into affected areas at least once every day until the condition clears. Both of these drugs help to shorten the life of the mites. It is possible that the skin might look worse for a few days after starting treatment, but this is alright. The immune system of the dog is fighting as hard as it can against the mites and trying to heal the damage to the skin.
Generalized demodex mange is much more difficult to treat. The veterinarian will prescribe shampoos and dips to help remove the scaly skin and kill the mites. Sometimes removing what is left of the dog's fur is necessary to have access to all infected areas. The shampoos and dips contain a strong insecticide called amitraz to kill the mites, currently this is the only miticide approved by the FDA for topical use on dogs.
There is also an oral medication that can be used to treat dogs with generalized demodex mange. However, it is important to note that the FDA has not officially approved of its use in this form so any use of the medication is strictly off-lable. Most often the drug of choice is ivermectin. This should sound familiar if you are a dog owner. This is because ivermectin is used in heartworm medications. The use of this drug for treating demodex mange must be strictly monitored by a veterinarian because of the risks involved with using such high levels of the drug. Typically the dosage starts off low and gradually increases until it reaches a therapeutic level. Once it reaches a therapeutic level it is maintained until the dog has two negative skin scrapings for demodex mites.
It is extremely important to note that if ivermectin is not used properly it could result in the death of the dog. For this reason ivermectin therapy and heartworm medications cannot be used at the same time. It is recommend that a month long detox is needed before the dog can be safely put back onto a heartworm regimen. Interestingly enough most herding dogs, particularly collies (including boarder collies, shelties, Australian shepherds, and old English sheep dogs) are very susceptible to the side effects of large doses of ivermectin and should never be placed on an ivermectin treatment for demodex mange.
Infections in the skin should be treated as recommended by a veterinarian by antibiotics. It is important to note that some antibiotics and anti-itching medication will not be used since they run the risk of lowering the dog's immune system. Since demodex mange is only a problem because of a weak immune system these medications would be counter productive.
It is also recommend that dogs that do recover from demodex mange should not reproduce. This is because they could pass on their weaker immune system to their offspring, thusly making their offspring more susceptible to demodex mange.
With all the advances in veterinary technology the prognosis for demodex mange is good. In fact most vets agree that a dog that has completely overcome the disease should never have a relapse, provided that the dog remains healthy. It is advised that the dog get regular skin scrapings as recommended by your veterinarian to insure that the mage does not come back.
With proper care your dog should be able to live a full and healthy life. Most, if not all, of the fur should grow back as well. Scar tissue doesn't often develop fur, but the rest of the dog's body should be covered in fur by the time the dog has been fully treated.
if you have ever had a sick dog before it should come as no surprise that treatments can be expensive. Demodex mange is no different, in fact it is going to be a long and expensive road to recovery. While localized mange can be cleared up fairly quickly with a little miticide shampoo and dips generalized mange is not so lucky. The treatment for generalized mange is going to last several months and coast several hundred dollars.
To help protect healing skin and keep her warm during winter, dog clothes can be useful.
In the End
The main thing to keep in mind about the differences between demodex mange and scaroptic mange is that demodex mange is an autoimmune disorder that does not affect dogs with healthy immune systems. Demodex mange is a nasty disease that can effect dogs at any age, though it is more commonly seen in younger dogs. Thankfully, with all the advances in veterinary medicine it is possible that a dog can make a full recovery.
Further reading about demodex mange and its treatments can be found on these sites: