What are dust mites?
Dust Mites are tiny creatures that are nearly invisible to the naked human eye. The ones that are linked predominantly with asthma are commonly called House Dust Mites, since they are found in house dust. There are about 13 different types of Mites which have been found in house dust, of which 6 types are found around the world. Two types of Mites are found in North America. They belong to the group called Dermatophagoides.
Dust Mites are blind, eight-legged bugs that are related to spiders and ticks, measuring about 1/100th of an inch in length. They are so small that six of them will fit on the end of a pin.
The numbers of Dust Mites seem to peak in July and August, and allergens remain at high levels through December.
Organisims found in household dust, or that produce household dust:
House Dust Mites, Silverfish, Cockroaches, Itch Mites, Corrociedtia, Pet hair skin and scales, human hair skin and fibers, food crumbs etc. Make up what can be found in a single gram of household dust. Mite dust can stay in the air for up to two hours.
Dustmites: What they Eat and How they Live:
Unlike some types of Mites, the House Dust Mites are not parasites of living plants, animals or humans. The main foods of these bugs are dead skin cells like dander that are regularly shed by humans and animals. Other things that they eat are fungi that grow on the skin, molds, insect bodies or parts (i.e. carpet beetles, silverfish, moth and butterfly scales, and cockroaches), pollen grains, bacteria, skin scales of birds, and dead plant matter.
The Dust Mites leave droppings everywhere they go. Their feces have enzymes leftover from what they used to consume and digest their food. These enzymes are the main part of what causes asthma and other allergic diseases. Many people tend to blame pollen or animal dander for their asthma and allergy problems, when, in truth, Dust Mites and their droppings are the main cause of asthma worldwide. The symptoms are usually repiratory, not a rash, though there have been reports of a red rash around the neck. Unfortunately there is no cure for Dust Mite allergies, only prevention.
A Dust Mite thrives in warm and humid conditions, and their favorite spot to live is in mattresses, pillows and bedding where you leave behind dead skin cells and body fluids you excrete when you are sleeping. More Mites are found in bedrooms in general than in any other room in the house. Dust Mites are so tiny that your mattress may contain as many as two million of theses little scavengers at a time. If you choose to vacuum the mattress, know that they can hang on quite well to avoid being sucked into the vacuum, but vacuuming will still remove some of the dust on which the Mites feed and a little of their droppings.
Dust Mites also live in dust that accumulates in places like carpets, upholstery and other textiles in homes. They burrow into the materials to escape the light, and the fibrous and cellular structure of these materials, allow them to cluster and reduce water loss. And carpeted floors harbor a great deal more Mites than tile or wood floors. The type of pile that the carpets have, also make a difference. The short, tight-piled carpets have fewer Mites than the long loose-piled carpets which actually seem to provide a microhabitat for the accumulated food and water that favors Mite survival, and offers them protection from removal by vacuuming.
Dust Mites do not drink water, but they absorb moisture from the air and surroundings. They eat more and develop faster in higher temperatures of 70-80 degrees F and humidity levels of 70-80%. They do not survive well at low humidity levels, and temperatures over 140 degrees for an hour is lethal to these mites.
How can I get rid of these Mites?
It is not simple, and not enough to get rid of the mites alone. To improve conditions for the allergy sufferer, you must get rid of the mites and also nearly all the dust which they may have left throughout your home over the years. It's a big effort and very expensive for most people, though it can be worthwhile. But be aware that no matter what you do to your home, you still breathe in Mite dust in other places than home. Also, do not make the treatment worse than the disease. Some people get obsessive about cleaning, and cripple themselves socially in an effort to avoid Mites. There is no single remedy for getting rid of Dust Mites, and Mite control will not work for you if you are not allergic to Mites. If you mean it though, be thorough.
Using allergen barriers and a consistant washing routine in combination though, can lower the number of Dust Mites found in a bedroom considerably.
Here are several suggestions of steps that you can take that will help reduce the effects of the Mites and limit their numbers.
- Encase box springs, bedding and pillows in an impermeable rubber or vinyl plastic, or in zippered dust-proof bedding covers. They also need to be permeable to water vapor so sweat will not accumulate next to the skin, and should enclose the mattress, pillow(s) and comforters completely. Although research has shown that versions which didn't cover the bottom of the mattress completely worked just as well. Clean the bedding covers regularly according to the manufacturer's instructions. Using non-allergenic comforters and pillows won't work as a substitute to covering them with the special dust-proof covers. All non-allergenic means is that the pillows are synthetic.
- It is also important to launder all uncovered items regularly. Wash your sheets, blankets and pillow(s) every week in very hot water of about 130 degrees F. This has been proven to kill all Mites. Be aware that temperatures over 120 degrees F can burn children if they turn on the hot water by themselves. Washing in cold water removes about 90% of the Mites, and dry cleaning kills all Mites and effectively removes dust from bedding items. Heat can also be applied by other means such as superheated steam cleaning of carpets, tumble-drying laundry, exposing to direct sunlight, or dry heating with electric blankets. A study has shown that using an electric blanket for eight hours a day reduced the dust mites in mattresses by half in one month.
- Wash clothes more often than you normally would. It is possible that clothes, including sweaters and dressing gowns are a prominent source of Mite dust.
- Control and suppress other insect pests such as cockroaches, fleas, and silverfish to minimize the extra allergens in the house.
- Keep the humidity in your home below 70%.
- Make sure your home has good ventilation. Consider heat exchangers to keep your house warm but ventilated.
- Minimize air infiltration which allows pollen, another major source of allergen for many people and food for Dust Mites, to enter.
- Regularly vacuum the carpets, furniture, textiles and furnishings like draperies to keep Dust Mite populations reduced.
- Avoid wet-mopping which increases air moisture, or if you must wet mop, it is a good idea to vacuum thoroughly first.
- Don't give furry stuffed animals to children to take to bed. A better choice is to give them a little cotton blanket which can be washed regularly in hot water of about 130 degrees F to get rid of the Mites.
- Replace cloth-upholstered furniture with dust-proof furniture such as wood, plastic or leather furniture. It may be more expensive, but you may be fighting a lost cause without doing so.
- Replace your carpets with sanded and/or varnished floorboards, or a vinyl linoleum, or tiled floor. When someone walks over a carpet, Mite dust is put into the air and takes about two hours to settle. Use a few throw rugs instead and wash them several times per year.
If you live in an area where getting rid of your carpets is not possible, then you do have a few other options. Purchase a high-quality vacuum cleaner; do what you can to reduce the humidity inside your home; cover the areas of your carpet that are walked on the most with throw rugs you can take out and wash. Think about replacing your home's carpet more often - you might consider a less-expensive type of carpeting so it can be replaced more frequently at a more affordable cost.
Here are some other tips for dust removal in your home:
- Damp dust with a slightly damp cloth rather than vacuum to keep the dust from flying about.
- If your Asthma is really bad, consider moving to another area where your asthma may be much milder, or moving to a newer house which has great damp-proofing.
- When traveling, take dust-proof bedding covers with you and use them on spare beds in other people's homes or on hotel beds. Then wash the covers as soon as you get home.
- Sleeping bags that are rarely used can be dry cleaned immediately when you get home and then promptly stored in an air tight plastic bag.
- The allergic person should not be the one doing the vacuuming or be around while the vacuuming is being done. Almost all vacuum cleaners, even the ones with good filters take and disperse a surprising amount of Mite dust into the air from the surfaces they are "cleaning". There are some vacuums that work better than others, but if you as the allergic person have to do the vacuuming and bed-making, wear a good filter mask, even though it might be uncomfortable and not very convenient.
- Special air filters that can help decrease the Mite dust in the air.
There is research being done involving the effects of vapors from wintergreen and 56 other plant oils such as anise, birch, coriander, lemon grass, nutmeg, pine, spearmint and ylang-ylang that kill Dust Mites in clothing, or in near proximity to their vapors. But in particular, Wintergreen is the most effective killing Dust Mites not only in small areas like storage boxes, but also in larger areas like closets. But the clinical usefulness and safety of these oils isn't clear yet.