TWO TYPES OF MANGE COMMONLY FOUND ON DOGS
BY: Susan Adams
Our neighbor's puppy has the red mange. They say their veterinarian told them that the condition is not contagious. I don't believe this because several dogs in our neighborhood caught the mange from a stray dog last year. I don't want to start any battles but I sure don't want our retriever to go through the mange treatment again. Can you offer any suggestions?
First, let me explain that there are two different types of mange commonly found on dogs in this part of the country. One type is extremely contagious while the other type is not. Dogs get mange when their skin is infested by tiny mites. These mites can be seen with a microscope but are invisible to the human eye.
One type of mite, the Sarcoptes mite, spreads quickly from one dog to another and causes the infectious kind of mange known as scabies. The other type of mite, the Demodex mite, causes skin problems only in dogs whose immune systems are not working properly. While most dogs are naturally immune to the Demodex mite, those dogs which cannot protect themselves against the mite develop red mange, also known as demodectic mange.
Demodex mites are transmitted to puppies from their dams during the nursing period, and a few mites survive on most dogs throughout their lives. These mites only cause mange in dogs whose natural immunity is weakened or who inherit a defective immune system which does not protect against the Demodex mite.
Young dogs tend to have weaker immune systems, and red mange is most frequently seen in puppies less than one year old. Often, short-term treatment will control the Demodex mite until a young dog's immune system is strong enough to ward off the red mange on its own. If a dog has inherited a defective immune system, however, lifelong treatment may be necessary. When an older dog suddenly develops demodectic mange, it is often because a disease such as cancer has weakened the dog's immunity.
Treatment for both types of mange requires weekly or biweekly dips. The only effective dip against demodectic mange, however, is a stronger chemical than the dip commonly used for sarcoptic mange. Veterinarians have been successful in treating sarcoptic mange with a drug which can be injected or given by mouth. Some oral drugs show promise as treatments for demodectic or red mange, but, due to expense and possible side effects, they are used only in cases which are not controlled by dips.
Because each type of mange has its own specific treatment, it is important to know which type of mite is infesting a dog with signs of mange. Veterinarians use a microscope to scan samples scraped from the skin of dogs with mange. Demodex mites are usually easy to find on skin scrapings from dogs with red mange. Sarcoptes mites are more difficult to find, even with repeated skin scrapings. If no mites are found but the clinical signs and history of a dog with mange suggest scabies, the dog should be treated for sarcoptic mange.
If your neighbor's puppy has the red mange, the Demodex mites should not be contagious to your dog. In addition to treatments with the correct dip, your neighbor should also take steps to minimize stress on their puppy's immune system. Insuring good nutrition and neutering the dog at an early age help to prevent stress. Neutering is also recommended to prevent passing on the hereditary defect in immunity which makes dogs susceptible to outbreaks of red mange.