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How To Avoid Dust Mites
By: MORRIS NEJAT, MD
If you start to suffer from allergies, dust mite allergy is one of the more common diagnoses you are likely to be given before you leave the doctor's office. In 1967, dust mites of the species Dermatophagoides were discovered to be a major source of allergens. (An allergen is any substance that causes an allergy or allergic reaction.). Dust mites are extremely small members of the Arachnid class and Acari subclass, and as such they are similar to spiders and "cousins" to lice and ticks. People with dust mite allergy are allergic to both the organism and its feces. The symptoms include itchy and runny eyes, itchy nose, sneezing, coughing, wheezing, and dry, itchy skin.
Do You Have Dust Mite Allergy?
If you have allergy symptoms around house dust, other possible sources of allergy can include cockroaches, domestic animals, mouse and rat dropping, and molds. One can even probably find significant levels of pollen in house dust during allergy season. This is why it is important for you to have skin testing done by an allergist to help pinpoint your allergies. This way, when you go to the inconvenience and expense of environmental avoidance, you can avoid the specific things to which you have allergies. I have seen patients who gave away the family cat and then found out it was a dust mite allergy that was making their child sick, or others who have gone through rigorous dust mite avoidance measures only to find out they weren't allergic to dust mites at all.
After undergoing skin testing, patients are often defensive about their housekeeping habits. I often hear, " I'm a good housekeeper and I dust everyday." Although this may be true, dust mites can live and thrive in places that dusting can't reach.
Dust Mites: Up Close and Personal
With a little effort, you can significantly decrease your exposure to dust mites and as a result decrease the allergy symptoms resulting from dust mite exposure. But to defeat the dust mite, we must first understand how it lives and thinks.
The Diet of the Dust Mite:
Believe it or not, the dust mite loves to eat our skin, especially the skin cells which we naturally shed and which fall off our body.
The Habitat of the Dust Mite:
Dust mites tend not to be airborne, primarily because they are too heavy but also because there is no food (i.e. dead skin) in the air (unless you have very bad dandruff or flaky body skin. So, we find high concentrations of dust mites in bedding, in clothes, in upholstered furniture, and, to a lesser extent, in carpeting. Jumping up and down on the bed or extensive cleaning may for a short time send the the dust mite adrift in the house (giving those with a dust mite allergy a good excuse to go to the beach while someone without dust mite allergy is vacuuming and/or some other anti-dust mite activity).
Dust mites like to live where there is abundant food, moisture, and warmth. For dust mites, this often means our bed. Our bed is the ideal spot for dust mites in some of the same ways as it is for us: we like to sleep there because it's cozy and toasty! But also, we as humans tend to lose most of our skin in the bed. And that's good news for our hungry dust mite bed companions.
But dust mites proliferate anywhere there is warmth and humidity, not just your bed. That is why when you open up your shore house in May (assuming you are lucky enough to own one), you may experience some violent sneezing and wheezing. The place has been sealed for 6 months with little or no circulation. As a result, any moisture present when the house was closed up for the winter has been trapped, producing favorable conditions for dust mites, as well for molds
Keeping Dust Mites Out: The Bedroom Battleground
When planning to battle the dust mite, we must concentrate on the area where our attack will be most effective. And that means protecting ourselves from the dust mite in our bedroom. It is a place where many of us spend much of our time, thinking we sleep safely and snugly—all the while not knowing what we may be actually breathing in! With our heads nestled into the pillow, we allow the dust mite relatively easy access to our respiratory passages.
There are a number of things that can be done to decrease exposure to dust mites in the bedroom. You could sleep in a hammock that is washed weekly in hot water. Although this is highly effective, it is relatively impractical and a remedy that I don't usually recommend. Fortunately, there are other, easy and practical steps that can be taken:
1. Place an impermeable dust mite encasing around the mattress , box spring and pillow. This type of encasing has vinyl on the inside and cloth on the outside to trap dust mites, but does not crinkle like plain vinyl. It also makes you sweat less than with plastic covers. One note of warning: Some of my patients have reported dramatic improvements in their allergy and asthma symptoms after the placement of the dust mite covers on their beds, while others haven't noticed a significant improvement even after a few months.
2. Wash all bedding that is placed on top of these covered items in water over 130 degrees. Achieving this temperature can be a problem in some apartment buildings where the thermostats on the hot water heaters have been lowered to prevent scalding in children and the elderly. I would recommend a pot of boiling water to be added to the hot cycle to raise the water temperature. If it is not practical to wash certain types of the bedding, like an expensive down comforter, placing it in a bag and putting in the freezer overnight is a good alternative.
3. Remove unnecessary objects from the wall and ceilings.
4. Keep stuffed animals to a minimum. If a stuffed animal can be washed weekly in hot water, then it's probably okay for your child to sleep with it. All others should be kept in a closed toy chest.
5. Use window blinds that can be wiped rather than curtains.
6. Remove carpeting, if possible. If your children are allergic to dust mites, they should be encouraged not to play on carpets.
7. Consider using products that kill dust mites, such as benzyl benzoate or tannic acid. These products have been shown to have some benefits in homes where there is wall to wall carpeting which can't be removed.
Hepa filters are also used, but I don't recommend them. These "air cleaners" don't do much. Spend your money on dust mite covers; you'll get more bang for your buck.
These steps seem like a lot of effort, but it will be worth it if you suffer from a dust mite allergy. And scientific evidence to prove it.
Scientific Evidence for Avoidance
There is good scientific evidence that dust mite avoidance works. A number of studies have been published in the scientific literature demonstrating the importance of dust mites in the development of nasal irritation and congestion (allergic rhinitis) as well as allergic asthma. Of more interest here is that there is substantial evidence demonstrating that dust mite avoidance decreases the symptoms of dust mite allergy in allergic people.
Most of the studies demonstrating the efficacy of dust mite avoidance have been done with severe asthmatics. One study, for example, took children with severe asthma caused by dust mites and placed them in a clinic in the Swiss Alps for 6 months. All of the children experienced a dramatic improvement in their asthma symptoms. Upon returning to their homes, their asthma symptoms returned to their prior state.
Similar improvements have been reported for dust mite–sensitive asthmatics who lived in hospital rooms for an extended period of time. This means that if you are allergic to dust mites, your bedroom should be as much like a hospital room as is feasible. A hospital room is good because it has a plastic mattress, tile floors, plastic furniture, and very little clutter. All of the bedding is washed in extremely hot water every day. (If not, would you want to sleep in a hospital bed?).
Although dust mites are everywhere, a few simple environmental measures can dramatically improve your allergy and asthma symptoms as well as decrease the amount of medication you may now require. Dust mite avoidance is the safest and among the most effective ways to treat allergies.