People use the word “mangey” a lot, typically to describe dogs with dirty and unhealthy fur. Recently, an owner used the word but then asked me about the origins as she had heard about dogs having “mange”. This is, in fact, a medical condition and not one restricted to dogs. Humans, cats, and many other animals also get mange.
Mange refers to the clinical condition caused by an overgrowth of skin mites. Many animals, humans included, have mange mites that live within the skin and do not cause any problems. However, if there are enough of them or the body reacts poorly to their presence, this will manifest as conditions such as rosacea and swollen eyelids. There are many kinds of mites, but the most common ones fall into two categories: Demodex and Sarcoptes. Like in humans, they can stay hidden in pets unless they are young, sick, or on immunosuppressive medications like steroids.
Sarcoptes, also called Scabies, are little spider-like buggers that tend to stay near the surface of the skin and cause itching and hair loss. In pets, this occurs mostly on the legs and ears. Demodex are longer, more caterpillar-like insects that burrow down deep into the skin and around hair follicles. Demodex doesn’t tend to be itchy unless it is a specific species. Otherwise, owners notice more generalized hair loss with swelling of the skin and folliculitis (pimple-like lesions at the hair follicles). Most puppies are born with demodex and can live their lives without ever seeing a skin lesion unless there is an issue with their immune system.
Both types are diagnosed by scraping away the surface of the skin in an affected area and looking at the sample under the microscope. With demodex, we can also pluck hair and find them wrapped around the base. However, we don’t always choose the right spots when we guess where to scrape. So, a negative scrape does not always rule out mange. In refractory cases, we will then have to biopsy the skin.
Treatment used to be difficult. We would need to use stinky or dangerous dips for bathing to kill the mites. However, progress in other medications has had a happy side-effect for our fight against mange. As topical flea and tick medications have become less & less effective over the years, there have been developments in oral medication that don’t eventually lead to tolerance issues down the road. While these have already been safe and effective against fleas and ticks, an unexpected bonus is that they kill mange as well, even with normal use. These medications, called isoxazolines, will kill 90% of mange within the first month of normal use. By the end of the 2nd month, all mange is typically eradicated. So, where it would difficult and frustrating rule-out mange in past, we often don’t even have to look for it with most dogs nowadays as 90% are on one of the oral flea and tick products. For those that are not, we simply have the owners switch to this preventive and the problem is solved in under 2 months.