For millions of Americans, the world is a sneezy, wheezy place, filled with normally harmless substances that their bodies recognize as enemies. Of all the enemies, there's one almost no one can escape: house dust.
House dust is the main allergen.
Between 40 million and 50 million Americans have some type of allergy. They sneeze or wheeze. Their noses get stuffy, runny and itchy. Many people with allergies have asthmatic reactions. They cough, wheeze and get short of breath as their bronchial passages narrow.
What makes lowly house dust such a plague to allergy sufferers? Just one speck contains a host of things that cause an allergic reaction - dust mites, human skin particles, animal dander, parts of cockroaches, mold spores, food particles and other debris.
The mighty mite
Those dust bunnies around your house are home to dust mites. These tiny critters are about 1/100th of an inch long (smaller than the period at the end of this sentence). Up to 18,875 dust mites can live in 1 gram of dust. The usual population is about 100 to 500 mites per gram.
About 10 percent of the population and 90 percent of people with allergic asthma have positive skin tests for allergy to dust mites. Almost half of young people with asthma are allergic to dust mites.
You can't avoid house dust and the mites who live in it. Dust mites are in our pillows, mattresses, carpeting, upholstered furniture and even books.
Dust mites like humidity too. They grow best when humidity is higher than 40 percent. In Denver, where it is very dry, you won't find any dust mites.
How does a mite make you sneeze?
Normally, the immune system defends the body against invading agents like bacteria and viruses. In an allergic reaction, the immune system responds to a false alarm.
The immune system treats the allergen - in this case the dust mite - as an invader. It attacks by making large amounts of a type of antibody (a disease-fighting protein) called immunoglobin E, or IgE. Each IgE antibody is specific for one unique allergen.
With dust mites, people react to proteins in the bodies and digestive waste (feces) of the mites. When you put your nose right next to the mattress or pillow, you inhale the antigen.
Dust busting tips
A dirty house can make a house-dust allergy problem worse, but even normal housekeeping may not be enough to relieve house-dust allergy symptoms. Allergists say there are steps you can take to reduce your exposure to it and to the pesky mites:
- Clean your home thoroughly on a regular basis. Vacuum frequently and dust with a damp or oiled cloth. Ideally, someone other than the dust-sensitive person should clean. If that's not possible, wear a dust mask.
- Get rid of carpeting, especially in the bedroom. Carpeting is a breeding ground for dust mites. If you must have carpet, choose one with low pile. Scatter rugs that can be washed each week are a better option. Wood floors or seamless vinyl or linoleum floor coverings are best because they can be cleaned easily and mites don't like to live on bare floors.
- Put a barrier between your nose and dust mites by covering pillows and mattresses with zip-lock vinyl covering.
- Wash bedding in the hot-water cycle (temperatures of 130 degrees F to 140 degrees F) to kill off dust mites.
- Use washable curtains and shades, not blinds, which collect too much dust.
- Use closed bookcases and curio cabinets instead of open shelves. Books and knickknacks - and, of course, stuffed animals - are dust collectors.
- Change or clean air conditioner and furnace filters often.
- Use air conditioning to keep inside humidity at 50 percent or lower. This slows mite growth during warm-weather months. Check with your allergist about room/home HEPA filters. A HEPA filter, which stands for high-energy particulate air filter, works well for airborne allergens like pollen. It can be useful for someone with a cat or dog allergy, It's not really useful for dust mites.
In general, Overholt says, "the more severe the dust mite allergy, the more rigid your dust avoidance ritual should be."
This article was reviewed and updated June 2007.
|
