Dust mite is a tiny animal related to ticks and spiders that lives in people’s homes. Dust mites, known officially as house dust mites, are less than 2/100 inch (0.5 millimeter) long. They thrive in places that are relatively moist and warm, such as bedding, carpets, and upholstered furniture. Their chief food is dandruff and other skin flakes, which make up much of the “dust” that accumulates in houses. Mattresses provide an ideal environment for dust mites, because sleeping bodies shed skin and produce moisture and warmth all through the night. Researchers have counted more than 40,000 dust mites in 1 ounce (28 grams) of mattress dust.
Dust mites are medically important because their bodies and waste products are among the world’s most widespread allergens. An allergen is a substance that causes an allergic reaction in people who are sensitive to it. Some studies show that as many as 10 to 15 percent of people react to dust mites. Inhaling dust mite allergens can trigger asthma, a condition that narrows the air passages in the lungs and hampers breathing. Skin contact with dust mite particles can also cause eczema, an allergic reaction that makes skin red, irritated, and itchy.
Eliminating dust mites is difficult, but certain measures help limit their numbers. Experts recommend that allergic people put protective covers on their mattresses and pillows and avoid carpeting their bedrooms. Periodically applying certain chemicals may help control mites in other carpets. Vacuuming carpets and upholstered furniture weekly may also help, as does washing bedding regularly in hot water.
