A Mite in a Rough Situation for Dogs

MITES ON DOGS

Could your dog’s skin problems, possibly including incessant scratching and licking, be something more than allergies? If your pup is losing fur, scratching like crazy, perhaps showing reddened areas of skin, and you can’t find any fleas, then it could be one of several skin diseases called “Mange.” Mange occurs when the skin is infested with one of several different species of mites that embed themselves either in or on your dog’s skin or in the hair follicles.

Mange is usually treatable, but some forms can be highly contagious and this condition has the potential to become very serious.

It sounds unpleasant, but mange occurs when mites set up camp on your dog’s skin. Some types of female mites may burrow into the skin to lay eggs, setting off further intense itching, inflammation and hair loss. How do dogs get mange? This usually happens after dogs are exposed to another infected animal – perhaps at the dog park. It could take two to six weeks for the signs to appear. Worse yet, a few types of mange mites can also spread to humans after contact with an infected dog.

There are several types of mange that could affect dogs including: canine scabies, ear mites, canine demodicosis, and trombiculosis.

A visit to your family vet is imperative to get a diagnosis, determine the specific type of mite on your dog, and get a treatment recommendation.

Here are a few things to be aware of when heading to the vet hospital.

CANINE SCABIES

Highly contagious, canine scabies is caused by a specific mite called Sarcoptes scabiei var canis. In other words, a little parasite that causes damaged skin and crusty sores. The female mites burrow tunnels in the skin to lay eggs and while this particular mite prefers dogs, there is a chance that humans and other animals coming into contact with an infected dog may also contract the mites. Also, indirect contact, such as through bedding, is a possible pathway for spreading these mites.

A dog infected with canine scabies mites will usually have intense itching that comes on suddenly.

Infested areas of skin can erupt with small, solid bumps that first appear on the dog’s abdomen, chest, ears, elbows and legs; however, these can be hard to spot. The dog will scratch or bite itself to relieve the itching and the bumps and surrounding skin become damaged, leading to thick, crusted sores and red areas of skin. Yeast or bacterial infections can develop in the damaged skin. Without appropriate diagnosis and treatment, the sores can continue to spread over the entire body and the infections can be fatal.

Sometimes, these mites are hard to find and diagnose, even when the dog shows signs of infestation such as severe itching.

This may happen when a dog is regularly bathed and well-groomed and because of this, the other typical signs – crusty sores and scaly skin – are removed by regular bathing. Nonetheless, if mange is suspected, your veterinary practitioner will want to run appropriate tests – perhaps evaluating several different areas of skin. Because mange is so contagious, you should speak to your personal physician if you have any concerns about your own skin.

Any treatment needs to also include any other dogs that have been in contact with the infected dog. The treatment recommended by your veterinary practitioner may include cutting the dog’s hair and soaking with a medicated shampoo to carefully clean areas of crusty skin. Newer, very safe, oral treatments to control mites may be given. Antibacterial treatments to eliminate any secondary bacterial infections may also be required.

EAR MITES IN DOGS (OTODECTIC MANGE)

This form of mange is caused by mites known as Otodectes cynotis, which infest the external ear canal – the part of the ear between the ear flap that you can see and the ear drum, which you cannot easily see. These dog mites cause inflammation of the lining of this ear canal.

The mites are usually not seen because they are found in the lining of the external ear canal in places that are not easily seen without the right otoscope equipment, although sometimes these mites are found on the skin outside the ear.

The infested animal (a dog or most commonly a young cat – rabbits also have their own type of ear mite) will frequently shake its head and scratch one or both ears. Dogs that have upright ears may have a drooping ear as a result, and in any dog infested with ear mites, the external ear may be inflamed and produce pus. Ear mite infections can also contribute to a torn eardrum or a haematoma developing on the ear pinna.

These mites are also very contagious and any other dogs or cats that have been in contact with the infested dog will need to be checked and possibly treated. Your veterinary practitioner will recommend a treatment plan that will likely include medication and ear cleaning. There are new, safe oral treatments that are very effective for eliminating ear mites.

CANINE DEMODICOSIS

The mites, called Demodex canis, that cause this form of mange are often found in small numbers in the hair follicles of all dogs and are perfectly normal, causing no sign of disease.

Under some circumstances, dogs may become infested with large numbers of these mites, resulting in hair loss and inflammation.

The reasons that this occurs are variable and not always known, with some evidence of hereditary predisposition for the condition, based on a weakened immune system which normally keeps these naturally occuring mites under control and the skin looking healthy. Sometimes the occurrence is associated with an immunosuppressing disease or treatment.

“Localised demodicosis” is one of the two clinical forms of this dog mange and occurs on a few small, isolated areas of the body that can appear hairless, red and scaly. Localised demodicosis generally occurs in puppies less than a year old who appear to experience very little itching or discomfort from the condition. Many of these occurrences resolve without any treatment.

“Generalised demodicosis” is a severe skin disease that affects large areas of skin. It can include skin changes such as hair loss, red and swollen skin, increased pigmentation (darkening of the skin), raised lumps and scabs, or inflamed foot pads. Bacterial skin infections are common in dogs affected by mites and the associated signs can include enlarged lymph nodes, lethargy, fever and inflammation of the deeper skin layers.

Generalised demodicosis is a serious disease and always requires medical treatment. There are new oral treatments that have improved efficacy for controlling these mites. Medicated shampoos may be prescribed as well as antibiotics to control the secondary infections. Routine monitoring may be important to track the number of mites on the dog.

Owners of dogs with demodicosis should remember that treatment of the generalised form of the disease can take several months to clear up and recurrence within the first year of treatment is not uncommon. There may be inherited susceptibility to this disease and owners of dogs with this condition should consult with their veterinary practitioner before considering breeding.

Trombiculosis

This type of dog mange is associated with small juvenile mites often found at harvest time, and sometimes called “harvest mites”. They look like tiny spiders and may sometimes be seen on your pet as tiny, orange-red dots. They frequently cluster on the head, ears, feet or belly.

Signs of infestation are often an allergic reaction to the mites and include redness, bumps, hair loss and crusty skin.

Intense itching can be associated with this problem. Dogs contract trombiculosis by lying on the ground or walking in an area where there is material with a heavy mite population.

Like other forms of mange, once your veterinary practitioner has diagnosed trombiculosis, the treatment is likely to include a combination of shampoos and medications, as well as possibly antibiotics for secondary infections. 

In Conclusion

There is no surefire way to prevent your dog from getting one of these types of mange, although using an effective flea and tick treatment can significantly reduce the risk. In general, healthy dogs handle mites better, so keeping your dog in good shape with a high quality diet and clean environment is helpful. Above all, if you see signs of skin disease, take your dog to your vet to catch and treat mites before they harm your dog further.