Dust Mite Allergies

Dust Mite Allergies

They're so small that scientists have counted thousands of these little critters on a single gram of house dust. But they cause big problems for an estimated 30 million people with dust mite allergies.

These microscopic organisms, which feed off flakes of human skin and food debris (and whose feces are potent allergens), live in dust. Besides causing the familiar symptoms of hay fever--sneezing, scratchy throat, stuffy or runny nose--dust mite allergies may also contribute to stuffed-up ears, especially during winter, according to Philip Fireman, M.D., director of allergy, immunology and rheumatology at Children's Hospital in Pittsburgh. They are also the culprits causing an eczema-like skin condition, and they have triggered many an asthma attack during their long and insidious history. But even though they're minuscule and fast on their feet, dust mites can be robbed of their might. Here's how.

Dehumidify your surroundings. Since dust mites live in dust, the obvious solution is to keep your house hospital-clean. But it's not necessarily the dust alone that keeps them thriving. It's the humidity. While air-conditioning helps reduce humidity, if you live in a warm or moist climate, you may also want to invest in a dehumidifier.

"Dust mites really don't do well at humidities below 45 percent," says Thomas Platts-Mills, M.D., Ph.D., head of the Division of Allergy and Clinical Immunology at the University of Virginia Health Sciences Center in Charlottesville. While 45 percent humidity is fine for a home at 70°F, at higher temperatures you need lower humidity. If the temperature is closer to 80°, the humidity should be below 40 percent.

Encase your mattress in plastic. The highest concentrations of dust mites are in the bedroom, where they love to dig their eight legs into mattresses, carpeting and pillows. The answer? "Encasing in plastic is a very easy thing to do. You can buy plastic cases ready-made, or just use sheets of plastic sealed with tape to wrap the mattress like a Christmas present," suggests Richard Weber, M.D., chief of the Allergy/Immunology Division at Fitzsimmons Army Medical Center in Aurora, Colorado.

Use a bedspread. Allan Weinstein, M.D., consultant to the National Institute of Allergy and Infectious Diseases in Bethesda, Maryland, recommends you keep a bedspread on your bed during the day and remove it from your bedroom at night. "Let the bedspread collect the dust--not you," he says.

Sleep on synthetic pillows. While dust mites like synthetic pillows as much as those made from feathers or foam, pillows made from Hollofil and Dacron have one important advantage--they can be washed. Be sure to wash all bedding, including mattress pads, bedspreads and blankets--and do it weekly in hot water. It's one of the best ways to kill dust mites.

Throw down some throw rugs. Deep-pile wall-to-wall carpeting is another taboo for the mite-allergic. The best flooring is hardwood or linoleum. "Mites can't survive on a dry, polished floor," says Dr. Platts-Mills. "And that kind of floor dries in seconds." A steam-cleaned carpet takes weeks to dry.

Short-pile area rugs--throw rugs--are much more acceptable, because they can be washed at temperatures hot enough to kill dust mites. The floors underneath--courtesy of a rug's loose weave-also stay drier than they would under wall-to-wall carpeting.

Stop mites with a mask. A simple chore such as vacuuming can throw huge quantities of dust into the air, where it will hang for several minutes, says David Lang, M.D., assistant professor of medicine and director of allergy/immunology at Hahnemann University School of Medicine in Philadelphia. A small mask that covers nose and mouth, known professionally as a dust and mist respirator, can cut the allergens reaching your lungs. An inexpensive version is made by the 3M Company and can be found in most hardware stores.