Dust Mites

Just thinking of these dust mites living in your pillow by the millions, eating your dead skin and hair is enough to make even Gov. Arnold Schwartznegger sick. The are a major cause of asthma and allergies; especially in vulnerable individuals, such as children and the elderly. According to the American College of Asthma, Allergy & Immunology, approximately 10 percent of Americans exhibit allergic sensitivity to dust mites. In the spring, pollen aggravates allergies, and dustmite infestations make it worse. The Fall and Winter months are a particular problem, as we close up our houses and the concentrations of dust mites and their feces increases inside. And with dustmites at their multiplying peak during warm, wet weather, read on to find out what you can do about dust mites!

House dust mites are microscope bugs that primarily live on dead skin cells regularly shed from humans and their animal pets. Dust mites are generally harmless to most people. They don’t carry diseases, but they can cause allergic reactions in asthmatics and others who are allergic to their feces. People sometimes confuse dustmites with bed bugs. Skin cells and scales, commonly called dander, are often concentrated in lounging areas, mattresses, frequently used furniture and associated carpeted areas, often harbor large numbers of these microscopic mites. Since the average human sloughs off 1/3 ounce (10 grams) of dead skin a week. That gives dust mites a lot to eat. Cats and dogs create far more dander for dust mites to eat.

A typical mattress can contain tens of thousands of dust mites. Sick yet? Nearly 100,000 mites can live in one square yard of carpet. Ready to convince your spouse to start bathing regularly? Did you know a single dust mite produces about 20 waste droppings each day, each containing a protein to which many people are allergic. Yuck! The proteins in that combination of feces and shed skin are what cause allergic reactions in humans. Depending on the person and exposure, reactions can range from itchy eyes to asthma attacks. And finally, unlike other types of mites, house dust mites are not parasites, since they only eat dead tissue. Gross, but true. Beds are a prime habitat (where 1/3 of life occurs). A typical used mattress may have anywhere from 100,000 to 10 million mites inside. (Ten percent of the weight of a two year old pillow can be composed of dead mites and their droppings.) Mites prefer warm, moist surroundings such as the inside of a mattress when someone is on it. A favorite food is dander (both human and animal skin flakes).

Humans shed about 1/5 ounce of dander (dead skin) each week.

About 80 percent of the material seen floating in a sunbeam is actually skin flakes. Also, bedroom carpeting and household upholstery support high mite populations. For most people, while they are disgusting, house dust mites are not actually harmful. However, the medical significance of house dust mites arises because their microscopic cast skins and feces are a major constituent of house dust that induces allergic reactions in some individuals. There is a genetic predisposition to dust mite allergies, but like many allergies it can also develop over time.According to Darryl C. Zeldin, acting director of the National Institute of Environmental Health Services, in the Wall Street Journal (January 5, 2010, Page D2), 18% to 30% of Americans are allergic to dust mites’ waste products, and almost 50% of American homes have allergen levels that are high enough to cause sensitivity in people who were nt previously allergic to dustmites. In other words, high levels of dust mites and their wastes, can cause previously non-allergic people to develop an allergy. In addition to producing allergic reactions, dust mites can also cause nasal polyps growths within the nose.
Beds are a prime habitat (where 1/3 of life occurs). A typical used mattress may have anywhere from 100,000 to 10 million mites inside. (Ten percent of the weight of a two year old pillow can be composed of dead mites and their droppings.) Mites prefer warm, moist surroundings such as the inside of a mattress when someone is on it. A favorite food is dander (both human and animal skin flakes). Humans shed about 1/5 ounce of dander (dead skin) each week. About 80 percent of the material seen floating in a sunbeam is actually skin flakes. Also, bedroom carpeting and household upholstery support high mite populations.

House dust mites, are too small to be visible to the naked eye; they are only 250 to 300 microns in length and have translucent bodies. It takes at least a 10X magnification to be able to correctly identify them. The adult mite’s cuticle (covering) has simple striations that can be seen from both the dorsal (top) view and from the ventral (bottom) view. The ventral view of the house dust mite reveals long setae (hairs) extending from the outer margins of the body and shorter setae on the rest of the body. Through the microscope, one will see many oval-shaped mites scuttling around and over one another. There are eight hairy legs, no eyes, no antennae, a mouthpart group in front of the body (resembles head) and a tough, translucent shell, giving a “fearsome appearance.”

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