Mite is a term used to describe a group of insect-like creatures related to ticks and that can usually only be seen under a microscope. There are almost as many types of mites as there are insects, including plant feeders, scavengers and mites that prey on insects and other mites. Some species of mites, such as those in the sarcoptic scabiei and demodex groups that live on dogs can affect humans.
The sarcoptes scabiei group of mites affects humans and canines by producing scabies in humans and sarcoptic mange in dogs. There are several species of sarcoptes scabiei mites and each prefer a different host species. However, as mite species can live for a short period of time on non-preferred hosts, dog mites in the sarcoptes scabiei group can temporarily live on, and produce symptoms in, humans.
The demodex group of mites is also a common mite affecting dogs. However, this group of mite lives in the hair follicles of most humans and dogs without producing symptoms. When a dog or human experiences symptoms from demodex mites, it usually indicates an underlying health condition called red mange, follicular mange or puppy mange.
Human Symptoms of Mite Infestation
Demodex mites do not generally produce symptoms in people. Dog mites in the sarcoptes scabiei family, however, can create intense, but temporary, itching on human skin. Because mite species in this family that are adapted to living on dogs can only survive temporarily on humans, the itching and redness will generally resolve in three weeks or less, unless the dog is not treated and the person comes into continual contact with new populations of mites.
Recognizing Dog Mite Symptoms
For the health of the dog and the owner, Pet Education recommends becoming familiar with the signs and symptoms of mite infestation. Sarcoptes scabiei mites burrow into a dog's skin, causing sarcoptic mange, which generally creates severe itching leading to hair loss, small red pustules, yellow crusts on the skin and secondary skin infections. In more advanced stages, the dog's skin may darken and his lymph nodes may enlarge.
If demodex mites produce red mange, it is usually a sign of a poorly functioning or underdeveloped immune system, such as in puppies. Ninety percent of dogs with red mange will have a few localized patches of lesions with hair loss and crusty red skin, possibly appearing greasy or moist. Ten percent of localized red mange cases will progress to a generalized mange, in which the lesions appear across the body.
As long as the source population on the dog in proximity is killed, humans affected by sarcoptes scabiei mites from dogs, specifically, do not require treatment, as the mites will die on their own. Dogs, however, need to be treated in order to kill the mites and avoid transmitting populations to other dogs and humans.Treatments include medicated lotions, dips and shampoos, though some of these treatments may be toxic to humans and should be administered under the advice of a vet, according to Pet Education. Selamectin (Revolution), Frontline Plus, Frontline Top Spot and Frontline Spray are less harsh options. Liquid ivermectin has also been used by vets as an off-label treatment for sarcoptic mange.
Demodex mites are also treated with medicated lotions, dips and shampoos, though many dogs recover on their own.