By Pierre Mouchette | Real Property Experts LLC
Human skin is crawling with microscopic insects called mites. These mites have an affection for hair follicles, especially on eyelashes and in the nose.
There are more than 65 species of parasitic mites, but only two live on human beings. Both species can be found on the face, chest, back, groin, and buttocks.
The eyelash mite (Demodex folliculorum) - prefer living on hair follicle, and typically live in groups with a few mites sharing a follicle. The adult mites are between 0.3 mm and 0.4 mm long, with a semi-transparent body.
The face mite (Demodex brevis) - prefer to live near sebaceous glands (produces oil that keep the skin and hair moist). These glands also cause pimples and acne when they become clogged or infected. The adult mites are up to 0.2 mm long, with a semi-transparent body. These mites appear to be loners, and generally only one will occupy a given follicle.
Research shows that the older you are, the more face mites you have tucked away in your facial follicles. Newborn babies are mite-free, but by age 60, virtually all humans are infested with face mites. A healthy human adult is colonized by 1,000 to 2,000 follicle mites at any given time, without ill effects. Face mites are believed to spread from person to person via close contact.
Facial mites have eight stubby legs and long, thin heads and bodies that allow them to move in and out of narrow hair follicles with ease. Face mites are tiny, measuring a mere fraction of a millimeter long. They spend their lives head-down in the follicle, gripping onto the hair or lash tightly with their feet.
The mites eat skin-cells, hormones, and oils (sebum) which accumulate in the hair follicles. Their digestive system is so efficient and results in little waste that they have no excretory orifice. At night they leave the hair follicles and come out to mate. Eggs are laid deep in the hair follicles or oil glands and are impossible to wash out. You must wait for them to hatch, and then treat the mites.
Scientists believe facial mites only lay one egg at a time because each egg can be up to half the size of its parent. The female deposits her eggs inside the hair follicle, and they hatch in about three days. Within the span of a week, the mite progresses through its nymphal stages and reaches adulthood. They live about 14 days.
Mites usually only come out of their follicles at night, since they are photophobic, and try to avoid light. They move very slowly, about 1 cm (half an inch) per hour.
The most common disorder, called demodicosis, is caused by an overabundance of mites on the skin and hair follicles. Symptoms include itchy, red, or burning eyes; inflammation around the eyelid; and crusty discharge around the eye. Seek medical treatment if you have any of these symptoms, which can also indicate other health issues besides mites.
People suffering from rosacea and dermatitis tend to have a much higher number of face mites on their skin than persons with clear skin. Large face mite populations have also been found on people suffering from other dermatological disorders, such as alopecia (hair loss), madarosis (loss of eyebrows), and infections of hair and oil glands on the head and face. These are uncommon, and the link between them and mites is still being studied.