Steve Tvedten's "The Bug Stops Here"
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The term "house dust mites" has been applied to a large number of sightless, eight-legged, microscopic arachnids called mites (smaller than a speck of salt) found in dwellings associated with dust. About 80% of dust in a building is us; each one of us sheds several million cells daily or about the weight of a paper clip. A family of four could fill a quart container in a month! Dust mites breathe through their skin and have a hypopial stage that makes them virtually immune to synthetic insecticide poisons and fumigants during this deep dormancy stage of life. They love warm, humid settings and feed on skin scales and dander shed by humans and animals. Hundreds can be found in one pinch of dust. Household dust is a microscopic blend of sloughed skin cells, sneezed viruses, soil, furniture and clothing fibers, pet dander, carpeting pieces, soil, mold, bacteria, insect fragments, etc. The average U. S. home collects 40 pounds of dust per year, which is home to at least 15 species of mites that live about 45 days and one ounce can contain over 42,000 individuals.

ECONOMIC IMPORTANCE: 35 million people in the U. S. suffer from dust mite allergy symptoms. In England, 1/3 of all cereal foods inspected had dust mite contaminations. Because of the medical implications, house dust and the fauna of mites associated with house dust have been tested for the source of the house dust allergen. The highest house dust allergen activity was found in dust samples stored at 85% RH. Mite allergens are mainly present in feces of house dust mites and may become airborne and inhaled by patients giving rise to asthma, rhinitis, or atopic dermatitis. Mite cultures contain so much allergen that a millionth of one per cent is still reactive to allergic people per Judith A. Mollet of Virginia Tech. This is suburbia's most common allergen. The second most common allergen is the pet cat whose dander, hair and saliva are all allergens. In the Northeast the cockroach is the most important allergen. Even the most spotless buildings house millions of dust mites. It is estimated that humans shed about 400,000 particles of skin a minute!

DISTRIBUTION: Nearly cosmopolitan, associated with house dust, bedding, carpets, furniture and bird nests.

HOSTS: Mammals, particularly man, and in bird nests and occasionally in bee hives.

DESCRIPTION: A sightless, microscopic (1/100 of an inch long) creature that lives in carpeting, drapes, bedding, upholstered furniture and stuffed toys. They prefer temperatures in the 68o - 84o F. range. Both male and female adult house dust mites are globular in shape, creamy white and have a striated cuticle. The female measures approximately 420 microns in length and 320 microns in width. The male is approximately 420 microns long and 245 microns wide. (About the size of a sharp pencil dot. They look like miniature hairy dinosaurs, complete with armor plates and pincers.)

Adults are about 1/100" to 1/64" long with soft, oval, somewhat flattened bodies. They are very dependent on temperature, moisture and an adequate food supply. While these microscopic mites, which are relatives of spiders that feed on our dead (moldy) skin, are found in the United States, they are much more prevalent in England where humidity is very high (over 50%), so use a dehumidifier and a fan with an activated charcoal filter. You provide their food in the form of dead skin cells that fall off your body each day. As Heywood Banks, the singing comedian, has written in a song, "Those dust mites smack their bony lips and eat that skin like taco chips. It's a rain of manna from the sky." Dust mites are easily controlled when they are exposed to direct sunlight so hang your wash out on a clothesline or steam clean all items.

House dust mites often cause allergic reactions. Dust mite feces contain at least 15 proteins that act as allergens. These mites and/or their droppings may cause allergic reactions to 500 million people worldwide and be responsible for triggering reactions in 50% to 80% of asthmatics! The University of Virginia estimates hospital emergency rooms see over 200,000 asthmatics a year with allergic reactions to dust mites. Female house dust mites can deposit 50 eggs in her 36 day (average) life span. Each mite can deposit 20 fecal pellets a day. So you can see how they can totally overwhelm your area very quickly with allergens that are normally "recycled" every time you vacuum or dust. For more information call 1-800-7-ASTHMA and 1-800-422-DUST.

DUST MITE SPECIES: There are several species worldwide including the House Dust Mite, Euroglyphus maynei, the American House Dust Mite, Dermatophagoides farinae (Hughes) and the European House Dust Mite Dermatophagoides pteronyssinus (Trouessart). Cast skins, fluids, feces and body parts of house dust mites accumulate with other dust and small household allergenic disintegrated matter. Vacuum with a Hepa filter intensely. A new and effective control method is to spray carpet with tannic acid solutions obtained from carpet cleaning suppliers. We prefer that you mop and routinely clean/dust and/or use a rinse-and-vac with diluted Safe Solutions, Inc. Enzyme Cleaner with Peppermint.

LIFE STAGES AND BIOLOGY: The life cycle of 2 mite species D. farinae (Hughes) and D. pteronyssinus (Trouessart) include egg, active larvae, resting larva (pharate tritonymph), active tritonymph, resting tritonymph (pharate adult), and active adult. Between 19-30 days are needed to complete a life cycle depending upon the temperature and humidity (Furumizo, 1973). Mated females live about 2 months. A male may attach itself to a tritonymph female and mate when she reaches the adult stage. D. farinae lays eggs over a 30-day period, producing about an egg a day, while D. pteronyssinus lays about 80 eggs over a 45 day period. There is a general agreement that house mites in the home feed on shed skin of man. The average individual sheds 0.5 to 1.0 gram of skin daily. Each dust mite can excrete 20 fecal pellets in a day, or an amount of excrement equal to 200 times its own weight in a lifetime. Spieksma et al. (1971) reported that the mites were very sensitive to relative humidity and at 60% or lower the mite population stops growing and dies out, so install a dehumidifier and fans. Safe Solutions, Inc. Enzyme Cleaner with Peppermint will control not only the dust mites but the fungus Aspergillus repens which predigests human skin flakes into a form the mites can eat.

Non-Toxic Control:

  1. Reduce the relative humidity with properly installed dehumidifiers, fans and/or air conditioners. Routinely remove (if possible) any dander, dead skin and/or dust and/or dust catching materials, e.g., books, magazines, clutter, stuffed animals, rugs, textiles, furs, feathers, woolens, drapes, carpets, etc. and/or enclose mattresses, pillows, and box springs in plastic and clean and/or wash or spray all surfaces and air filters with Safe Solutions, Inc. Enzyme Cleaner with Peppermint as needed. Install allergen trapping filters in air conditioning/heating systems. Keep all clothing in closets with the doors closed. Keep windows closed in the spring. Clean the air with HEPA air filtration.

  2. Avoid sleeping with or keeping pets - especially cats and dogs or wash often with 1 - 2 oz. of Safe Solutions, Inc. Enzyme Cleaner with Peppermint. It is best to keep your pets outside; if you can not, HEPA vacuum daily and wash your hands after petting your pet. Dander stays around long after the pet has gone.

  3. Keep windows and doors closed and as weather-tight as much as possible to avoid the entry of pollen and insects. Clean window coverings every two weeks or replace with shades or mini-blinds.

  4. Keep food products in glass containers and control all insect pests.
  5. Reduce the relative humidity below 50%; repair all plumbing/moisture problems; install a dehumidifier and/or air filtration system. Hot air vents should be covered with HEPA filters.

  6. Avoid wet mopping and dusting unless you use diluted Safe Solutions, Inc. Enzyme Cleaner with Peppermint (1 oz. per gallon of water). Then use Safe Solutions, Inc. Enzyme Cleaner with Peppermint in a rinse-and-vac or spray diluted Safe Solutions, Inc. Enzyme Cleaner with Peppermint, but vacuum very thoroughly with a rinse-and-vac, vacuum with a HEPA filter at least once a week - go very slowly and allow the vacuum to actually suck up all materials; dust furniture and shelves before you vacuum. Carefully and slowly vacuum beds, pillows, drapes, carpet, upholstered furniture, floors etc. Steam clean everything. Don't allow smoking in the building.

  7. Shampoo or steam clean or dry clean (off premises and air out thoroughly before returning) or better yet, simply put in to the sun all non-washable carpets at least one a year.

  8. Weekly washing sheets, pillows, rugs and carpets in soapy water or borax at least 122o F. for 5 - 8 minutes will kill all mites.

  9. Direct sunlight also kills mites and bedding is the prime harborage for dust mites, with stuffed furniture a close second. So put furniture, bedding, drapes, clothing, etc. out in the sun and/or line dry your washing. Replace heavy drapes with washable shades, mini-blinds or lightweight curtains.

  10. Put plush toys in a plastic bag, tie the bag and freeze for 24 hours. Repeat as needed, e.g.. once a week or wash them weekly. It is best to only purchase washable stuffed toys and wash them weekly with Safe Solutions, Inc. Enzyme Cleaner with Peppermint in water (100o - 120o F.).

  11. To control dust and dust mite allergens take a (square box) window fan, using duct tape attach two (charcoal) furnace filters (cut to size) to the fan grills on both the intake and exhaust sides. Turn on the fan to filter the air. Activated charcoal will increase the filtration results and help remove odors and some toxic gases. Change filters as needed. You can also use a high-efficiency HEPA air cleaner.

  12. Over 25% of an old pillow might be dust and dust mites - so get a new one every 6 months. Remove carpeting, rugs, stuffed animal toys and drapes if needed.

Least-toxic Control:

  1. Routinely steam clean and/or mop and clean with Safe Solutions, Inc. Enzyme Cleaner with Peppermint or alcohol. Then, if you still have any allergic reactions, as a last resort, you may have to try to clean with borax (½ cup per gallon of hot water). Houses severely infested with dust mites might require more cleaning with Safe Solutions, Inc. Enzyme Cleaner with Peppermint and/or borax to reduce mite allergens to tolerable levels (less than two micrograms of allergen per gram of dust).

  2. Clean any mold in the basement, bathrooms, kitchen, etc. with diluted bleach or borax or, better yet, with 2 oz. of Safe Solutions, Inc. Enzyme Cleaner with Peppermint per gallon of water.

MORE METHODS TO MANAGE DUST MITE ALLERGIES - Caution: Children's bedrooms may be hazardous to their health. Kids occupy them a third or more of each day, and while there, come in close, long-term contact with bedding, carpeting and other fibers. While these furnishings can be comforting touches, they also contain most allergy sufferers' biggest enemies: dust mites. Microscopic arachnids, these 8-legged spider-like scavengers thrive in humid and warm conditions, shedding particles that trigger symptoms even after the insects cease to exist. Remove the fuzzies - wool blankets and non-washable stuffed toys. Install medical-grade air cleaners, use dustless vacuums and obtain other less costly aids that keep allergies at bay. Humans shed about 1/5 oz. on dead skin (dander) every week. About 80% of the "dust" seen "floating" in a sunbeam is actually shed skin flakes. Dust mites can only eat dead skin flakes (both animal and human) that have fungus growing on them. Safe Solutions, Inc. Enzyme Cleaner with Peppermint (1 - 2 oz.) and/or borax (½ cup) per gallon of water kill the fungus and eliminate their food source and also kill dust mites.

The first hurdle to overcome: The bed. That's because a mattress is the resort capital of the dust mite's world. A double bed mattress can hold millions of mites; you feed them with you and your provide them with about 1 pint of moisture vapor each night through your breathing and perspiration. Pillows and blankets are popular too. Mattresses and box springs should be encased in zippered, dust-proof covers. Sleep movement (people toss and turn up to 60 times each night) kicks up allergens, which are then breathed in and/or can remain suspended in the air for up to 24 hours. Washing bed linens in hot water is crucial. Water below 120o F. prevents accidental scalding, but it must be 130o F. or you must use borax and/or Safe Solutions, Inc. Enzyme Cleaner with Peppermint in cooler water to kill dust mites. For hotter water without scalds, get an "instant flow" device that supplies hot water at a specific point of use, such as a washer. Because bunks, canopies and upholstered headboards attract dust, avoid them, and don't allow a bed to be placed on the floor as it fosters dampness because bedding can't breathe, and dampness means moisture - an ideal condition for mites. Try leaving an electric blanket turned on high during the day to dry the humidity and kill the dust mites in the mattress. Wash blankets in hot water and borax every two weeks. Avoid blankets made of wool or down or routinely wash them in 2 oz. of Safe Solutions, Inc. Enzyme Cleaner with Peppermint and/or 2 oz. of borax per gallon of water.

The next place to concentrate on is the floor. Mites claim it as private stomping grounds too. The University of Virginia maintains that carpets are likely to have 100 times more allergens than wood floors. Besides hardwood, tile and vinyl are good flooring alternatives. You will still need to remove traces of dust on them and on woodwork, however, by cleaning with water and Safe Solutions, Inc. Enzyme Cleaner with Peppermint, then wax or oil regularly. Even using a damp cloth with diluted Safe Solutions, Inc. Enzyme Cleaner with Peppermint or diluted alcohol every day helps. Small rugs and throws, if they are washable - and laundered often in borax - are all right. Low pile carpet usually is not as troublesome to an allergy sufferer as high shag. A vacuum with a high-efficiency particular air (HEPA) filter will capture particles without spewing exhaust dust, as a standard vacuum's paper filters does. A HEPA filter eliminates 99% of dust. There are chemical carpet products that reduce or destroy allergens - A moist powder is sold in all states but California. A tannic acid spray is acceptable there. A central or portable air purifier with a HEPA or electrostatic filter will remove particles and some dust mites - Keep in mind it is only effective on airborne irritants.

A refrigerated air conditioning system which, if ducts are professionally and routinely cleaned, can prevent hot and humid conditions that stimulate mite growth. Central heating ducts demand similar maintenance and synthetic filters to prevent dirt particles. Keep indoor relative humidity below 50% by using a dehumidifier, especially during humid seasons. Pets: Animal dander, saliva and other irritants, including dust that their fur collects, may cause allergic reactions, so keep them out of bedrooms or use an air filter.

Windows: Choose washable curtains or roller shades over draperies or blinds. When you clean, move all furniture to the center of the room so you can reach all of the corners and, with a damp cloth, wipe all of the moldings, light fixtures, shelves and door and window tops. Clean wood or linoleum floors daily with a specially treated dust cloth and mop cover. Don't use dusters, dust mops. bag-equipped vacuum cleaners or brooms - these utensils merely rearrange the dust or provide breeding grounds for additional dust mite/allergen growth.

Medical-grade air filters circulate and effectively clean up to 300 cu. ft. of air per minute. Inexpensive table top models generally are ineffective. 30 drops of tea tree oil in your sprayer, washing machine or rinse-and-vac will kill mold and dust mites. The distinct tea tree odor disappears when dry. Air out for 1 - 2 hours before re-entry. Repeat as needed. Metabolic gases emitted from molds and fungi growing inside buildings may be a significant source of volatile organic compounds (VOC's) that can cause indoor air quality problems known collectively as the "sick building syndrome". Spray or wash with 1 oz. Safe Solutions, Inc. Enzyme Cleaner with Peppermint per gallon of water. Tape an activated charcoal filter on both sides of a window fan - turn on and filter mites/dust from the air. Change filters as needed. Install and properly maintain dehumidifiers and/or air conditioning. Lower the relative humidity below 50% and control this pest. Remove all dust and dead skin routinely and thoroughly.

If you are still having problems with dust mites, & read The Best Control© or The Best Control II© on CD-ROM.


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