What is mange and what are the symptoms in dogs?

I am curious as to what the symptoms are? Is it more common in outside dogs than indoor dogs? What can be don’t to correct the problem? Mychocolate lab has tiny insect-bite-like marks on her ear flaps that are crusty and she has lost some hair and has thinning hair on her belly and chest. Thanks!

Sarcoptic mange, commonly known as canine scabies, is caused by the parasite Sarcoptes scabiei. These microscopic mites can invade the skin of healthy dogs or puppies and create a variety of skin problems, the most common of which is hair loss and severe itching. While they will infect other animals and even humans, they prefer to live their short lives on dogs. Fortunately, there are several good treatments for this mange and the disease can be easily controlled

The symptoms are varied, but usually include hair loss and severe itching especially on the elbows, ears, armpits, hocks, chest, and ventral abdomen (belly). The mites prefer to live on areas of the skin that have less hair. As the infection worsens it can spread over the entire body. Small red pustules often develop along with yellow crusts on the skin. Because of the severe itching and resultant scratching, the skin soon becomes traumatized and a variety of sores and infections can develop as a result. The itching seems to be much worse in warm conditions such as indoors or near a stove or heat vent. If the infection goes untreated or is mistakenly treated as an allergy, the skin may darken due to the constant irritation, and the surrounding lymph nodes may become enlarged.

Sarcoptic mange is a somewhat common infection and many cases have often been misdiagnosed as severe atopy (inhalant allergy). Any time we see a dog who does not have a prior history of allergies and develops severe itching, or if the itching is not seasonal but year-round, we have to suspect sarcoptic mange.

The intense itching caused by the sarcoptic mite is actually thought to be caused from a severe allergic reaction to the mite. When dogs are initially infected with Sarcoptes they do not develop itching for several weeks. If the animals are treated and then reinfected at a later time, severe itching starts almost immediately, which indicates the itching may be due to an allergic reaction. However, the standard treatments for allergies generally will not decrease the symptoms of scabies, and will do nothing to cure the disease.

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Learn more about Symptoms of Mange and different types, here.