This is the "before" picture I took today. I have high hopes that I’ll be showing you some much nicer "after" pictures in the coming weeks. "Lucky" is a stray dog who showed up about six weeks ago. The extremely nice man who adopted him tells me that he actually looks a little better after the treatments they’ve been doing, but it seemed to him like the progress was a little slow with the dipping treatment their previous doctor prescribed. What, you’re not happy with the whole body as a running sore?
You’ll hear a lot of folks refer to any dog with hair loss as "having the mange". Mange properly refers only to the skin diseases caused by an infestation of microscopic bugs from the mite family. One of the more common kinds is that caused by Demodex canis. These tiny bugs live deep in the hair follicles. Parasitologists tell us that a small number can be found on almost any dog, apparently causing no problems. When they over-multiply, they damage the hair follicle, causing the hair to fall out. If they continue out of control, they do enough damage that bacteria living on the skin take advantage of the "open door" and set up shop to cause a severe skin infection. In Lucky’s case, he now has deep pyoderma (pus in the skin that goes all the way to the lowest layers of skin). This is a pretty severe complication and is responsible for most of the discomfort experienced by the dog.
Dogs that are stressed by illness, pregnancy or simply rapid growth as puppies may experience transient bouts of localized demodecosis. This manifests as a small hairless spot or spots. The skin is smooth and it doesn’t seem to itch. The vast majority of these individuals will heal spontaneously as their own body defenses crank up and get the mites in check. They do not require treatment of any kind as a general rule, though persistent cases may benefit from topical treatment of the spots. Whole-body dipping is NOT indicated for these patients.
When the dog is more severely compromised, generalized demodecosis may result. Sometimes this happens with chronic illness in a young dog. If it happens in an older dog, you really need to search for some serious underlying disease. There are some dogs whose immune system simply does not recognize the mite as being a problem. These dogs mount no defense at all against the mites and they run rampant, with much secondary damage as well. Lucky could be one of these dogs, but we hope not. If the dog’s body defenses do not participate in the treatment, cure is unlikely.
Most dogs can be cured with today’s treatments. Thirty years ago the only treatment was daily dipping with a very toxic (and stinky) insecticide. It seldom worked. People tried everything from rubbing the dog with raw meat to burnt cylinder oil. They didn’t work. Then came amitraz, first in an orchard spray chemical, then the currently approved form called Mitaban. You bathe the dog in medicated shampoo to flush the debris from the hair follicles so the dip can get in. You dry the dog thoroughly for a few hours so that the follicles aren’t full of water. Then you soak him in the amitraz dip. If he soaks up enough to work, he feels a little bad or "drunk". Once per week seems to be the most effective regimen.
Daily oral treatments with high doses of ivermectin or milbemycin oxime are much less nasty to perform and (with ivermectin) actually cheaper than the dipping process. In many dogs this systemic treatment is more effective at killing the mites, as well.
In any case, prolonged treatment is needed to eliminate the problem. Treatment generally takes two to four months in a severe case like Lucky’s. One also needs to treat the secondary problem. In a severe case like this, dipping alone is unlikely to be successful. Lucky will need to take antibiotics for the skin infection for at least three weeks (the length of time needed to grow a new layer of skin). Nutritional supplements to boost his immune system are needed. We also need to get rid of any other debilitating problems (like the hookworm infestation that had not been treated yet). Medicated shampoos help clear the debris from his skin and hair follicles, depriving the parasites and bacteria of their support.
Look for Lucky’s first "after" picture in about two weeks.