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Thursday, January 31, 2013

How to Identify and Control Bed Bugs; Guidelines To Help Rid a Home of Bed Bugs. (Compiled by the Housing and Community Environment Program of the Allegheny County Health Department) What are Bed Bugs? bedBed bugs are small wingless insects that feed solely upon the blood of warm-blooded animals. Bed bugs and their relatives have evolved as nest parasites. Certain kinds inhabit bird nests and bat roosts and await the return of their hosts; others have adapted well to living in the ‘nests’ (homes) of people. Hatchling bed bugs are about the size of a poppy seed, and adults are about 1/4 of an inch in length. Looking from above they are an oval in shape, but are flattened from top to bottom when viewing them from the side. Their color ranges from nearly white (just after molting) or a light tan to a deep brown or burnt orange. The host’s blood may appear as a dark red or black mass within the bug’s body. Because they never develop wings, bed bugs cannot fly. When disturbed, bed bugs actively seek shelter in dark cracks and crevices. What Do Bed Bugs Do? Bed bugs seek out people and animals, generally at night while these hosts are asleep, and painlessly sip a few drops of blood. Bed bugs prefer the dark. While feeding, they inject a tiny amount of their saliva into the skin. Repeated exposures to bed bug bites during a period of several weeks or more causes people to become sensitized to the saliva of these bugs; additional bites may then result in mild to intense allergic responses. The skin lesion produced by the bite of a bed bug resembles those caused by many other kinds of blood feeding insects, such as mosquitoes and fleas. How Do Bed Bugs Get In Your Home? Because bed bugs readily hide in small crevices, they may accompany (as stowaways) luggage, furniture, clothing, pillows, boxes, and other such objects when these are moved between apartments, homes and hotels. Used furniture, particularly bed frames and mattresses, are of greatest risk of harboring bed bugs and their eggs. Thus, one should carefully scrutinize and consider the history of any used furniture, particularly ‘street’ items so plentiful at the beginning and end of each academic year. Because they readily survive for many months without feeding, bed bugs may already be present in apparently ‘vacant’ and ‘clean’ apartments. Bed bugs can wander between adjoining apartments through voids in walls and holes though which wires and pipes pass. Bed Bug Feeding Habits howdyBedbugs are generally active only at night, with a peak attack period about an hour before dawn, though given the opportunity, they may attempt to feed at other times of day. Attracted by warmth and the presence of carbon dioxide, the bug pierces the skin of its host with two hollow tubes. With one tube it injects its saliva, which contains anticoagulants and anesthetics, while with the other it withdraws the blood of its host. After feeding for about five minutes, the bug returns to its hiding place. The bites cannot usually be felt until some minutes or hours later, as a dermatological reaction to the injected agents. Although bedbugs can live for up to 18 months without feeding, they typically seek blood every five to ten days. Bed bugs hide in cracks and crevices during daylight hours. They hide in the folds and tufts of mattresses, coils of springs, cracks and hollow posts of bed stands bed rails and headboards. They may be found inside the cabinetry of furniture and the bottom and sides of drawers. They also can be found behind loose wallpaper, behind pictures on the walls, under door and window casings, and behind baseboards. However, they are not restricted to these places. It is important to recognize that not all bites or bite-like reactions are due to bed bugs. Bed bugs or their signs will be present if it is a bed bug bite. Bed bugs do not live under the skin. If you experience biting sensations during the day, it may be an allergy related condition. Bedbugs are often erroneously associated with filth. They are attracted by exhaled carbon dioxide, not by dirt, and they feed on blood, not waste. In short, the cleanliness of the infested environment has no effect on bedbugs. Their numbers may be reduced temporarily by vacuuming, but will recover and require vacuuming again. Health Effects on Humans signgWhile bedbugs have been known to harbor pathogens in their bodies, including plague and hepatitis B, they have not been linked to the transmission of any disease and are not regarded as a medical threat. Some individuals, however, can get skin infections and scars from scratching bites. While bedbugs are not regarded as a vector of transmissible diseases, they are a serious stressor and will create a lot of alarm and distress. With some individuals, it may precipitate mild to moderate cases of delusional parasitosis. How Do I Know If I Have Bed Bugs? You may notice itchy skin welts. You may also see the bed bugs themselves, small bloodstains from crushed insects, or dark spots from their droppings. It is often hard to see them because they hide in or near beds, other furniture, and in cracks. How Do I Search for Bed Bugs? Carefully inspect the bed frame, mattress, and other furniture for signs of bed bugs and their eggs. Although dead bed bugs, cast bug skins and blood spots may indicate an infestation occurred previously; they do not confirm that an infestation is still active. Search for live (crawling) bugs and ensure they are bed bugs before considering treating. Keep in mind the eggs can be as small as a poppy seed and the larvae as small as a grain of rice. Bed bug females lay about 200 eggs, usually at the rate of three or four a day, in cracks and crevices in the floor or bed. Eggs are placed in cracks, crevices and other isolated and protected shelters. Females lay eggs after a blood meal. Eggs will hatch in one or two weeks into Nymphs. Newly hatched bugs(Nymphs) begin feeding immediately. At room temperature, and with an available food supply, the nymphal period will last 14 to 30 days. They shed their skin (Instar)five times before becoming adults. Bed bugs will mate soon after becoming mature, so the time from egg hatch to egg laying will be 4 to 9 weeks, under favorable conditions. Bed Bug Management 1) Look For The Bugs swThe first step to getting rid of bed bugs is to do some investigative work. Remember that bed bugs are visible to the eye. Be prepared to inspect all areas of the room using a bright flashlight and a magnifying glass if you have one available. Bed Bugs can leave reddish- brown spots on mattresses and have a distinct smell. Remember that the bed bug's flat shape and small body enable it to hide easily in cracks and crevices. Bed bugs, eggs, larvae, and fecal deposits will go unnoticed with just a casual inspection. You should leave nothing unturned when doing your inspection for bed bugs and no site should be ignored that may be a bed bug harborage. Bed Bugs could be hiding anywhere! Examples are: wall sconces, behind electrical switch plates, behind wall posters, between books and magazines on shelves and in racks, or even inside an alarm clock, radio or TV. Be prepared to inspect all the places near sleeping areas, which may mean taking the bed frames apart! 2. Prepare The Area A thorough cleaning of the premises will make bed bug control efforts by you and the pest control contractor much more effective. Strip all beds down to the bare sleeping surface. Bedding (sheets, blankets, comforters, covers, and shams) should be washed in very hot water. Very hot water (120+degrees) will kill the bed bugs. Clutter should be removed from furniture tops, bed stands and under/around the bed. Open up the clock radio and phone (that's right, Bed Bugs may be hiding in there too!). Tap the open ends into a bag or on sticky tape so the bed bugs can’t jump and hide. In severe infestations, clothing should be removed from dressers and chests. Utilize a crack & crevice vacuum tool to remove bed bugs from deep harborage such as: under baseboards; under carpet edges (pull up along the tack strip); around switch plates (you may have to remove the plate first); from the bed frame; inside box springs; inside furniture; and from floor cracks. Use a hand-brush attachment to vacuum up most of the bed bugs. Vacuum mattresses and box springs (especially along seams and folds); upholstered furniture; and behind drapes. Also vacuum the floor completely. After vacuuming, remove the bag from the vacuum, tie it tightly, and remove it from the premises ASAP. Remember, really infested bedding may have to be completely discarded. Indirect measures can go a long way in controlling bed bugs: keep bats and birds away from houses; clean furnishings, launder bedding and mattress pads, and steam-clean mattresses. You may also prevent bed bugs from getting into homes by removing debris from around the house, repairing cracks in walls, and caulking windows and doors. 3) Physical Controls. Simple physical control methods include standing the legs of beds in soapy water, coating the legs with petroleum jelly or double-sided sticky tape. Bed bugs cannot climb polished glass or metal easily and they don't fly, so that the legs of beds can also be placed inside glass jars or metal cans. Move the bed away from walls and furniture. Do not use bedding that touches the floor. Wear night clothes/ pajamas with long sleeves and a high neck. 4) Chemical Controls. Chemical control includes the use of common insect repellents on exposed skin (OFF, 6-12, etc.) and applying residual insecticides in cracks and crevices. This can be done to supplement the treatment being applied by a commercial pest control company. Sprays containing natural pyrethrins can be used. Sorptive dusts such as fumed silica (also called diatomaceous earth) are useful in closed, hard-to-reach places. These pesticides can be purchased from local vendors (hardware stores, etc) and from several companies on the internet (see sources below). They can safely be applied by the occupant, as long as the directions on the label are followed. If you feel unsure about using pesticides yourself, they are best done by a professional pesticide applicator. Inorganic materials, such as silica gel, boric acid and diatomaceous earth will provide long term control when used in a dry, indoor environment with low humidity. These materials have very low repellency to insects and can provide good control when applied to cracks and crevices. Diatomaceous Earth is a good example. It is a natural, non-toxic substance made from crushed fossil shells of freshwater organisms and marine life (Old Coral reef). Crushed to a fine powder when seen through a microscope, the particles resemble bits of snowflakes through the lens. It is harmful to any insect and harmless to humans, animals, fish, fowl or food. How it works is that insects have a waxy outer shell covering their bodies and breathing surfaces. The microscopically sharp edges of Diatomaceous Earth and silica gel cut through this waxy layer, causing the bed bug to dehydrate and die. It is especially effective for crawling insects such as bed bugs. The mode of action is strictly mechanical. Bed bugs can not build immunities to this method of pest control such as with traditional pesticides. Liquid and aerosol (aka “Bug Bomb”) pesticide sprays containing either benzalkonium chloride or natural/synthetic pyrethrins can be applied to the whole room and as a spot treatment to cracks and crevices that may harbor bed bugs. These botanical insecticides will repel and knock down bed bugs for a time, but they deteriorate quickly and provide no residual action. The finish on some wooden furniture may also be damaged from the petroleum carriers contained in aerosol pyrethrins. Synthetic pyrethroids like Deltamethrin, lambda-cyhalothrin and others can provide good control if thoroughly applied to bed bug hiding places. They are long lived residuals and will not damage materials that are not harmed by water. Both liquid and dust insecticides are available in hardware stores, pharmacies, mail order catalogues and on-line via the internet. Professional Pest Control contractors can offer a few more pesticide formulations, but to be successful, they all require a very thorough application. There is no magic bullet. A couple of “do it yourself” web sites include www.bed-bug.net, and www.thebugstore.net (external links). Much more information on bed bugs is available from pest control contractors, county agents and university websites (such as this page from the University of Kentucky: www.uky.edu/ag/entomology, external link). Photographs from the Centers for Disease Control and Prevention and the Housing and Community Environment Program of the Allegheny County Health Department

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