Introduction to Dust Mites

Dust mites or house dust mites (sometimes abbreviated HDM) are not insects, but very small arachnids—so small that they cannot be seen with the naked eye. They have eight legs and a one-part body, and are related to dusts, daddy long legs, and ticks. Although there are plenty of urban myths claiming that mattresses double their weight in ten years due to dust mites and their detritus, or that there are two million dust mites in the average mattress, this is complete hyperbole. At the same time, dust mites’ feces, like mold and mildew, are potent allergens and their presence creates suffering for people with asthma and allergies. In fact, more people are allergic to dust mite dander than to anything else in their homes. Even those who aren’t allergic may suffer from eye, nose, and throat irritation on account of dust mites.

Because dust mites are so small and are in virtually every dwelling, the issue is not really to recognize them, but rather to keep them at bay. It is probably best to assume that they’re present in their usual haunts: carpeting, pillows, mattresses, stuffed toys, upholstered furniture, bed linens, duvet covers, and throw rugs, and also in the furry coats of your pets, even if your home is quite clean.

The reason dust mites thrive where they do is the warmth and humidity, as well as the readily available supply of scales of human and animal skin, their primary diet. One approach is to address each of these factors

• Environment—In general, you can use a dehumidifier to make sure home humidity levels stay below 50%. Good ventilation will also contribute to reducing the problem. Another step, urged by researchers at the Kingston University School of Architecture in London in an ongoing study publicized in 2005, is leaving one’s bed unmade. The reduction in moisture caused by allowing the bedding to air may create conditions under which the dust mites cannot survive.
  

  The other change you can make in the environment is by reducing the areas dust mites can dwell happily in: making flooring choices that don’t involve rugs or carpets; using plain (un-upholstered) furniture, where possible and comfortable; and covering mattresses, box springs, and pillows with allergen-proof coverings are additional steps you can take.

• Cleaning—Other than minimizing the places they can inhabit, cleaning is the main way to deal with dust mites. Here are some suggestions:
  
  • Regular grooming and bathing of pets is one step towards reducing the dust mites’ food sources.
    

  • Regular vacuuming, particularly with a central vacuum system with a high efficiency particulate air (HEPA) filter (wear a dust mask while vacuuming, if you have allergies) has been found to be essential. Vacuum the mattress and box spring on a regular basis, as well as rugs, carpets, and upholstered furniture.

  • Launder bedding, duvet covers, and pillow shams regularly. It is recommended that you use hot (>130º F (54.44ºC )) water. Wash children’s stuffed toys, as well.