Dust Mite Busters

(Wellness Letter, June 2012) – In greatly enlarged photographs, dust mites look like something from a horror movie. But they are actually on the clean-up committee: they eat our discarded skin cells, as well as animal dander, pollen, fungi, bacteria, and other microscopic organic material in the domestic environment. They thrive in mattresses, pillows, carpets, and clothing. Thousands of mites can live in just one gram of dust.

Dust mites don’t carry disease and don’t bite, fortunately, but they can trigger asthma, hay fever, and skin reactions in some people. In fact, dust mites are probably the most common indoor allergen, especially in warm, humid climates and for people with asthma. They are virtually nonexistent in very dry climates.

If you have asthma, a skin condition, or other reaction you think might be caused by dust mites, consult a board-certified allergist for a diagnosis. If mites are the culprit, try the following strategies:

·        Buy a good vacuum cleaner with a HEPA (high-efficiency particulate air) filter. Ordinary vacuuming will only send dust mites and their particles into the air. It’s not clear how much a HEPA filter actually helps with allergies, but it’s worth trying. Ideally, if you’re allergic, get someone else to vacuum and dust. Vacuum bags should be changed often, since mites and debris can get out.

·        If your allergies are severe, remove carpets and upholstered furnishings, especially in your bedroom. Install wooden or plastic blinds instead of drapes and curtains. Some products claiming to kill dust mites in carpets can irritate the respiratory tract.

·        Wash bed linens and blankets in hot water and use a hot dryer. (Dry cleaning may be less effective at killing mites—research is inconsistent.) Very hot water is best.

·       Use impermeable covers to encase mattresses and pillows (and blankets that can’t be washed), which can harbor lots of dust mites. Studies have been conflicting about how much this helps, however.

·       Replacing pillows periodically makes sense, which means you’re better off not buying pricey ones. Dust mites can infest all kinds of pillows—those made of feathers, polyester, foam, or other synthetics. There’s no consistent evidence that one type is preferable.

·       Since dust mites thrive under humid conditions, try using a dehumidifier in the bedroom in damp climates. In warm months, use an air conditioner, which helps lower humidity. Be sure bathrooms and laundry rooms are well vented—this reduces humidity in the rest of the house. Obviously, don’t use a humidifier.

·       Don’t bother with air purifiers or air duct cleaning services—they will do little or nothing to reduce dust mites.