Dust Mites
House dust mites are microscope bugs that primarily live on dead skin cells regularly shed from humans and their animal pets. Dust mites are generally harmless to most people. They don't carry diseases, but they can cause allergic reactions in asthmatics and others who are allergic to their feces. People sometimes confuse dust mites with bed bugs.
Skin cells and scales, commonly called dander, are often concentrated in lounging areas, mattresses, frequently used furniture and associated carpeted areas, often harbor large numbers of these microscopic mites. Since the average human sloughs off 1/3 ounce (10 grams) of dead skin a week. That gives dust mites a lot to eat. Cats and dogs create far more dander for dust mites to eat.
A typical mattress can contain tens of thousands of dust mites. Sick yet? Nearly 100,000 mites can live in one square yard of carpet. Ready to convince your spouse to start bathing regularly? Did you know a single dust mite produces about 20 waste droppings each day, each containing a protein to which many people are allergic. Yuck! The proteins in that combination of feces and shed skin are what cause allergic reactions in humans. Depending on the person and exposure, reactions can range from itchy eyes to asthma attacks. And finally, unlike other types of mites, house dust mites are not parasites, since they only eat dead tissue. Gross, but true.
Where do they live?
Beds are a prime habitat (where 1/3 of life occurs). A typical used mattress may have anywhere from 100,000 to 10 million mites inside. (Ten percent of the weight of a two year old pillow can be composed of dead mites and their droppings.) Mites prefer warm, moist surroundings such as the inside of a mattress when someone is on it. A favorite food is dander (both human and animal skin flakes). Humans shed about 1/5 ounce of dander (dead skin) each week. About 80 percent of the material seen floating in a sunbeam is actually skin flakes. Also, bedroom carpeting and household upholstery support high mite populations.
The University of Manchester performed a 2005 medical study of pillows that found up to 16 species of fungi in a single pillow. They tested feather and synthetic pillows in a range of ages, finding thousands of spores of fungus per gram of pillow ; more than is found on an average used toothbrush.
And just when you thought they were confined to your home and bedroom, there is a news story in USA Today in which Jill Holdsworth is an infection preventionist and president of the DC Metro Chapter of the Association for Professionals in Infection Control and Epidemiology says the car can be another place where dust mites live and a very big place to pass bacteria back and forth if you are not careful, saying "The No. 1 hot spots would be anywhere that you touch with your hands," Holdsworth said. These areas include the steering wheel, radio, gear shift, cup holders and car seats."
Are they harmful? What do they do?
For most people, while they are disgusting, house dust mites are not actually harmful. However, the medical significance of house dust mites arises because their microscopic cast skins and feces are a major constituent of house dust that induces allergic reactions in some individuals. There is a genetic predisposition to dust mite allergies, but like many allergies it can also develop over time.According to Darryl C. Zeldin, acting director of the National Institute of Environmental Health Services, in the Wall Street Journal (January 5, 2010, Page D2), 18% to 30% of Americans are allergic to dust mites' waste products, and almost 50% of American homes have allergen levels that are high enough to cause sensitivity in people who were nt previously allergic to dustmites. In other words, high levels of dust mites and their wastes, can cause previously non-allergic people to develop an allergy. In addition to producing allergic reactions, dust mites can also cause nasal polyps growths within the nose (see this article at 24 Medica). The constituents of house dust are show in the following figure:
Organisms in household dust:
Constituents
of
House Dust*
ash, cigarette; ash, incinerator; combustion products; fiber, synthetic textile; fibers: wool, cotton, paper and silk; fingernail filings; food crumbs; glass particles; glue; graphite; hair, human and animal; insect fragments; oil soot; paint chips; plant parts; pollen; polymer foam particles; salt and sugar crystals; skin scales, humans; skin scales, pets; soil; spores, fungal; stone particles; tobacco; wood shavings *Drawn primarily from van Bronswijk, 1981.
For those individuals, inhaling the house dust allergen triggers rhinitis allergica or bronchial asthma. People with allergies to house dust usually also have allergic reactions to house dust mite fecal material and cast skins. Studies have shown that the most potent house dust allergens can be extracted from the feces produced by dust mites. Other important allergen-producing organisms that are found in house dust are found in Figure 1. The rest of this fact sheet, based on Chapter 10, "Mites," in Common-Sense Pest Control by Olkowski, Daar and Olkowski, will discuss biology of dust mites and will emphasize non-chemical control tactics. An allergist, a medical doctor specially trained to treat allergies, should be consulted for proper diagnosis and treatment of allergies.
One of the most strongly allergenic materials found indoors is house dust, often heavily contaminated with the fecal pellets and cast skins of House Dust Mites. Estimates are that dust mites may be a factor in 50 to 80 percent of asthmatics, as well as in countless cases of eczema, hay fever and other allergic ailments. Common causes of allergy include house dust mites, cat dander, cockroach droppings and grass pollen. Symptoms are usually respiratory in nature (sneezing, itching, watery eyes, wheezing, etc.), usually NOT A RASH. However, there are reports of a red rash around the neck. Other allergic reactions may include headaches, fatigue and depression.
The wheeze-inducing proteins are digestive juices from the mite gut which are quite potent. An exposure to the mites in the first, crucial year of life can trigger a lifelong allergy. There is no cure, only prevention. One must control house dust mite levels.
Beds are a prime habitat (where 1/3 of life occurs). A typical used mattress may have anywhere from 100,000 to 10 million mites inside. (Ten percent of the weight of a two year old pillow can be composed of dead mites and their droppings.) Mites prefer warm, moist surroundings such as the inside of a mattress when someone is on it. A favorite food is dander (both human and animal skin flakes). Humans shed about 1/5 ounce of dander (dead skin) each week. About 80 percent of the material seen floating in a sunbeam is actually skin flakes. Also, bedroom carpeting and household upholstery support high mite populations.
How to Recognize the Symptoms of Allergies to Dust Mites
The protein substances in the dust mite feces produces antibodies in humans who are allergic when these are inhaled or touch the skin. These antibodies cause the release of histamines which causes to nasal congestion, swelling and irritation of the upper respiratory passages. The Mayo Clinic, WebMD and NIH collectively provide this list of typical symptoms of an allergy to dust mites; You may experience all or just some of them:
Hay fever, atering eyes,Runny nose, Sneezing,Asthma, difficulty in breathing,Infantile eczemaItchy, red or watery eyesNasal congestionItchy nose, roof of mouth or throatPostnasal drip CoughFacial pressure and painFrequent awakeningSwollen, blue-colored skin under your eyes In a child, frequent upward rubbing of the nose
A doctor can use skin tests and blood tests to confirm a suspected dust mite allergy. In a news story in the New York Times (March 4, 2011) Dr. Diego Saporta, an otolaryngologist in Elizabeth, N.J., who specializes in allergy management., says to ask: Do I have persistent sniffles and sinus headaches? Do I often wake up with scratchy eyes? Do I sneeze repeatedly first thing in the morning? “Sometimes symptoms are obvious, but sometimes they are subtle,” said Dr. Saporta says. “Your only symptom might be chronic nasal congestion.”
What else makes the symptoms worse?
Poor ventilationHigh humidityHigh temperatures (above 70 F / 20 C)Indoor air pollution such as tobacco smoke or car fumes.
Walking over a rug, sitting down in a chair, or shakings the bed clothes, makes the dried dust mite feces become airborne, making allergic person's symptoms worse.
Detection
House dust mite presence is often suspected before they are actually seen and accurately identified. Requests for control often come from individuals who have been diagnosed by medical personnel as allergic to the house dust mite or the allergens produced.
The presence of house dust mites can be confirmed microscopically which requires collecting samples from mattresses, couches or carpets. Also, it requires the use of a microscope with sufficient magnification and the technical ability to recognize house dust mites under the microscope. In general practice, testing is unnecessary. dustmites are extremely common in household environments. They virtually always show up in a test, so testing just adds expense. A better question than "are dust mites present?" is "How can I control or remove them?"
What Can You Do?
Control measures and Sanitation
A number of researchers, like those at the University of Nebraska, have studied dust mite control and have a set of recommendations that are proven to be effective. Recommendations focus on "dust control." One must reduce the concentration of dust borne allergens in the living environment by controlling both allergen production and the dust which serves to transport it. For the bedroom environment you will want to use some or all of the following methods. We have listed them in order of practicality combined with effectiveness.:
- The most effective means is to enclose the mattress top and sides with a plastic cover or other dust mite impervious cover (available here, click on allergy bedding on the left in the new page), thoroughly vacuuming mattress pillows and the base of the bed. Put an airtight plastic or polyurethane cover over your mattress. This is the method recommended by Consumer Reports (see their article here). This tip is number one for a reason: it is in your bed (including the baby's crib) that you are closest to the mites and their feces and enclosing the mattress and pillows in a dust mite cover virtually eliminates the mites here. There is a website, The Allergy Store, that we recommend that sells allergy controls, like the dustmite-proof fitted sheets. Mattresses covered with "fitted sheets" help prevent the accumulation of human skin scales on the surface. These sheets have the advantage of being waterproof, too, which helps protect your mattress from spills, babies and toddler's waste, too.
- Reduce temperature and humidity: Dust mites love warm, humid conditions, above 70 F (21 C) and 50% or greater humidity.
Temperature: Keep the thermostat in the house below 70 degrees.
Humidity: The National Institute of Health says an effective control of mites would require the maintenance of relative humidity's below 50 percent. Here is a range of dehumidifiers from a large basement or ground floor model, to a small room model. The big ones are pricey, but they last for many, many years. (we have one in the office that is 20 years old!)
A study (Feb 2005) by Kingston University (London UK) shows that simply by leaving your bed unmade each morning, with the sheets to be exposed to the air, allows the sheets to dry out, and substantially reduces the numbers of dust mites. Now, you have a legitimate reason not to make your bed!
Some researchers feel it is important to focus on decreasing indoor humidity, especially during the winter period to reduce dust mite populations. One might forsake humidifier use during winter periods (or limit it to the bedroom only at night, then ventilate the room during the day). It will help to use dehumidifiers during high-humidity periods, or use central air conditioning. So if you use a humidifier in the winter, adjust it to produce 35% to 45% humidity. Some humidifiers have this control built in; with others, you'll need a humidity gauge (usually sold with a thermometer at Costco, Sam's Club, Wal-Mart, Target, etc.). And generally, homes that have their air conditioners on constantly in the summer and dry heat in the winter have lower mite counts than non-air conditioned homes. - Wash your sheets, pillows and blankets in very hot water. Wash the sheets and blankets at least every two weeks. Wash your pillow every week or put a dust mite-proof cover (available here) on it and wash once per year. Your pillowcase goes over the dust mite cover. How hot is hot? The water used to wash your sheets and blankets should be at least 130°F (54°C). Set your washing machine to it's hottest setting. If the water doesn't seem to be coming out hot, you may want to check your hot water heater - you may not realize that most household hot water heaters have a knob that can adjust the temperature of the water it produces. For fabrics that may not be washed in hot water; just pop it into the freezer for 24 to 48 hours to kill dust mites.
And for those who travel and stay in hotels (or with less hygienic friends and family): Take a dust mite impervious cover (available here), along for when you stay at hotels - just think how disgusting their pillows must be! - Use Synthetic fabrics: Replace feather and down pillows with those having synthetic fillings. Replace woolen blankets with nylon or cotton cellulose ones. And don't forget the children's stuffed animals: be sure to get washable stuffed animals in the future! Memory foam mattress manufacturers claim that their mattresses create an environment that is unfavorable to dust mites. Even so, an encasement (dust mite impervious cover) is still advised, also because it can stop bedbugs (which are a rapidly growing problem)
- Clean weekly: Weekly change pillowcases, sheets, and under blankets, and vacuum the bed base and around the covered mattress. Clean flooring: Use a damp mop or rag to remove dust. Never use a dry cloth or broom, since this just stirs up mite allergens.
- Clean daily: Daily damp dust the plastic mattress cover.
- Frequently wash all bedding (blankets, mattress pads and comforters) in hot water (130 degrees F [or 60°C] weekly). Cold and warm water won't kill mites. Also wash curtains.
- Steam clean surfaces and materials that cannot put put through the washing machine: Using pure steam dissolves dirt and grime, while removing germs and bacteria from the surfaces that you're cleaning. Steam is also an economical and environmentally friendly thing to do. There is no longer the need to use harsh and toxic chemicals. It is also a great way to kill dust mites and bed bugs. See this steam cleaner: New Vapamore MR100 Primo Steam Cleaner.
- Remove carpeting and install laminate flooring, wood, tile, linoleum, or vinyl floor covering. Remove cloth drapes and blinds. (If you have carpet, vacuum every day.) Vacuuming your carpets and upholstery every week can help. See the caution about vacuuming below under tips. Vacuums with high-efficiency filters pick up more dust mites, but even standard vacuums work well enough.
- Freezing and sunlight kills mites but does not remove their residue. In addition to freezing temperatures and washing items in temperatures greater than 130 degrees F, extended exposure to sunlight, and low levels of humidity also destroy the mites.
- Children's soft cloth toys: Regularly place soft toys in the freezer for 24 hours before you wash them, or wash them in hot water. Removing them, or at least reducing the numbers of them on the beds, will help, too.
- Air Purifiers: While it is better to stop the dust mites at the source, reducing the dust levels in the air is a good secondary measure. Some pest control firms sell air purifiers to eliminate the food source of house dust mites. Although ozone air purifiers emit a low level of ozone (activated oxygen) that attaches to fungus, mold, and bacteria on skin flakes, EHSO does not recommend ozone generators (neither does the US Food and Drug Administration). The same ozone that is oxidizes the dust mites is bad for your health. Air purifiers that use HEPA filtration are more effective and safe to use. Various types of air purifiers can be attached to the central air return to decrease irritants. Most filters remove 50 to 70 percent of material. HEPA filters will remove up to 99 percent of the material; not just dust mite feces, but also all types of other allergens, like animal dander, dust, pollen, cockroach feces, etc... See this page for information about selecting an air purifier.
- Furnace Air Filters: Clean or replace the air filters on your furnace or air conditioner at least once a month. Filters that are rated to trap allergens are obviously more effective than plain spun glass.
BED BUGS
Bedbugs are small, oval, brownish insects that live on the blood of animals or humans. Adult bedbugs have flat bodies about the size of an apple seed. After feeding, however, their bodies swell and are a reddish color.
Bedbugs do not fly, but they can move quickly over floors, walls, and ceilings. Female bedbugs may lay hundreds of eggs, each of which is about the size of a speck of dust, over a lifetime.
Immature bedbugs, called nymphs, shed their skins five times before reaching maturity and require a meal of blood before each shedding. Under favorable conditions the bugs can develop fully in as little as a month and produce three or more generations per year.
Although they are a nuisance, they do not transmit diseases.
Where Bed Bugs Hide
Bedbugs may enter your home undetected through luggage, clothing, used beds and couches, and other items. Their flattened bodies make it possible for them to fit into tiny spaces, about the width of a credit card. Bedbugs do not have nests like ants or bees, but tend to live in groups in hiding places. Their initial hiding places are typically in mattresses, box springs, bed frames, and headboards where they have easy access to people to bite in the night.
Over time, however, they may scatter through the bedroom, moving into any crevice or protected location. They may also spread to nearby rooms or apartments.
Because bedbugs live solely on blood, having them in your home is not a sign of dirtiness. You are as likely to find them in immaculate homes and hotel rooms as in filthy ones.
When Bedbugs Bite
Bedbugs are active mainly at night and usually bite people while they are sleeping. They feed by piercing the skin and withdrawing blood through an elongated beak. The bugs feed from three to 10 minutes to become engorged and then crawl away unnoticed.
Most bedbug bites are painless at first, but later turn into itchy welts. Unlike flea bites that are mainly around the ankles, bedbug bites are on any area of skin exposed while sleeping. Also, the bites do not have a red spot in the center like flea bites do.
People who don't realize they have a bedbug infestation may attribute the itching and welts to other causes, such as mosquitoes. To confirm bedbug bites, you must find and identify the bugs themselves.
Signs of Infestation
If you wake up with itchy areas you didn't have when you went to sleep, you may have bedbugs, particularly if you got a used bed or other used furniture around the time the bites started. Other signs that you have bedbugs include:
- Blood stains on your sheets or pillowcases
- Dark or rusty spots of bedbug excrement on sheets and mattresses, bed clothes, and walls
- Bedbug fecal spots, egg shells, or shed skins in areas where bedbugs hide
- An offensive, musty odor from the bugs' scent glands
If you suspect an infestation, remove all bedding and check it carefully for signs of the bugs or their excrement. Remove the dust cover over the bottom of the box springs and examine the seams in the wood framing. Peel back the fabric where it is stapled to the wood frame.
Also, check the area around the bed, including inside books, telephones or radios, the edge of the carpet, and even in electrical outlets. Check your closet, because bedbugs can attach to clothing. If you are uncertain about signs of bedbugs, call an exterminator, who will know what to look for.
If you find signs of infestation, begin steps to get rid of the bugs and prevent their return.
Bedbug Treatments
Getting rid of bedbugs begins with cleaning up the places where bedbugs live. This should include the following:
- Clean bedding, linens, curtains, and clothing in hot water and dry them on the highest dryer setting. Place stuffed animals, shoes, and other items that can't be washed in the dryer and run on high for 30 minutes.
- Use a stiff brush to scrub mattress seams to remove bedbugs and their eggs before vacuuming.
- Vacuum your bed and surrounding area frequently. After vacuuming, immediately place the vacuum cleaner bag in a plastic bag and place in garbage can outdoors.
- Encase mattress and box springs with a tightly woven, zippered cover to keep bedbugs from entering or escaping. Bedbugs may live up to a year without feeding, so keep the cover on your mattress for at least a year to make sure all bugs in the mattress are dead.
- Repair cracks in plaster and glue down peeling wallpaper to get rid of places bedbugs can hide.
- Get rid of clutter around the bed.
If your mattress is infested, you may want to get rid of it and get a new one, but take care to rid the rest of your home of bedbugs or they will infest your new mattress.
Bedbug Extermination
While cleaning up infested areas will be helpful in controlling bedbugs, getting rid of them usually requires chemical treatments. Because treating your bed and bedroom with insecticides can be harmful, it is important to use products that can be used safely in bedrooms. Do not treat mattresses and bedding unless the label specifically says you can use them on bedding.
Generally it is safest and most effective to hire an experienced pest control professional for bedbug extermination.
