Science Snippet: Skin Mites

The top photo shows an adult human skin mite as seen with the scanning electron microscope; note the stubby legs. The bottom image is a depiction of mites on the surface of human skin, as well as in the follicle of an eyelash.

“You Almost Certainly Have Mites On Your Face” was the title of a National Geographic article that surely discouraged anyone who read it. Mites belong to the same group (Class Arachnida) as spiders, daddy longlegs and scorpions. Probably you are more fearful of spiders than the mites that live at the bases of your eyelashes or in your sebaceous skin glands. Since your mites are only 0.1-0.4 mm long, you don’t even know they are there. Out of sight, out of mind should be our mantra. The genus name of our mites is Demodex, which comes from Greek words that mean “boring worm.” Mites are rare on babies, more common on teenagers, and universal in adults. They have eight legs and a long abdomen that extends up to the surface of the skin. They feed on cellular debris and fatty secretions and most of us consider them rather nasty because they don’t poop. Their excreta continues to fill their abdomen until it swells and finally bursts, with the contents released onto your skin. You never know it happens! Remember: out of sight, out of mind. You don’t fuss about the bacteria in your gut, so get used to living with skin mites. (phenomena.nationralgeographic.com/2014/08/27; “Meet Your Mites,” robdunnlab.com/projects/meet-your-mites; news-medical.net/health)