Taking the Bite Out of Bed Bugs
(E1538, Revised February 2024)The common bed bug, Cimex lectularius, the species most adapted to living with humans, has resurged throughout the world and in many parts of the U.S. in recent years. This species was introduced to the U.S. in the 17th century by early colonists.
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Description
Adult bed bugs are oval, flattened, brown, wingless insects that are about 1/4 to 3/8 inch long (Fig. 1). Nymphs resemble adults but are much smaller, only 1/16 inch long, and colorless except after feeding (Fig. 2). Eggs are white, about 1/32 inch long and upturned at the tip (Fig. 3). Bed bugs have piercing, sucking mouthparts that they use to pierce the skin of their hosts to consume a blood meal (Fig. 4). After feeding, the abdomen elongates and the insect is more cigar-shaped and noticeably darker due
to the ingestion of blood (Fig. 5).
Bite Symptoms
Bed bug bites are painless and almost always occur while a person sleeps. Individuals may differ in their sensitivity to bites. Exhaled carbon dioxide, body heat and other chemical cues attract bed bugs to their hosts. Bed bugs inject saliva containing an anticoagulant and an anesthetic when they bite, and this causes the bite area to become irritated. Bed bugs feed mainly on exposed skin of the face, neck and arms. Feeding takes about five to 10 minutes. Typically, a small welt develops at the site of each bite. Rows of three or four welts are characteristic of bed bug bites (Fig. 6). Although bed bug bites may cause anxiety, stress and insomnia in their victims, bed bugs are not known to transmit any diseases. The fecal droppings of bed bugs pollute homes with allergens and may cause severe allergic reactions and asthma in some individuals.
Integrated Pest Management (IPM)
Detecting Bed Bugs – Hiding Spots
Bed bugs are secretive and may be found in any room in the house. However, research has shown that 85% to 90% of bed bugs are found in the bedroom on the mattress, box springs or within 15 feet of the bed. Dwellings with a high rate of occupant turnover, such as hotels, motels, hostels, dormitories, shelters, apartment complexes and prisons, are at higher risk of having bed bug infestations. If living in an apartment building, adjacent apartment units also should be inspected. Bed bugs can infest airplanes, ships, trains and buses as well.
Initially, bed bugs are located in bedding and mattress seams (Fig. 7). As bed bugs multiply, they spread to bed frames, plaster cracks, baseboards, partitions, loose wallpaper, dressers and even picture frames. Any habitat that offers darkness and isolation is a potential hiding place. They are spread readily to new locations in clothing, luggage, used beds and second-hand furniture. Since bed bugs can survive up to six months without feeding, they already may be present in vacant and apparently clean apartments.
Thoroughly examine mattress seams, box springs, bed frames, luggage, furniture cushions, peeling wallpaper, picture frames, wall baseboards, electronic appliances (TVs, radios and clocks) and other potential hiding areas for bed bugs. Use flashlights to inspect any dark hiding places. Also look for small rusty stains on mattresses and box springs about the size of this dot • (Fig. 8). These stains are made when bed bugs excrete liquid fecal drops after consuming a blood meal (Fig. 9). If sleeping people accidently crush bed bugs, reddish stains on bed sheets or mattresses can be observed. Eggs and casted skins of nymphs are another sign of bed bug activity. If a bed bug infestation is heavy, a pungent, sweet smell may be noticeable. Again, inspect all potential hiding areas thoroughly. Although expensive, dogs have been trained to detect the scent of bed bugs and may be useful in difficult cases.
Bed Bug Traps
Several types of bed bug traps are available. Sticky traps or glue boards have not been very successful in monitoring for bed bugs (Fig. 10). Because bed bugs are attracted to carbon dioxide and chemical cues such as lactic acid and octenol, baited pitfall traps, such as the Nightwatch™ trap (www.bedbugsupply.com/nightwatchbed-bug-monitor.html) have been developed and are commercially available. Another type of trap called the Climbup™ uses humans as the bait (www.jteaton.com/ bed-bugs/climb-up/). This trap uses bed beg behavior of climbing the legs of a bed. It has two concentric plastic bowls, with the inner side of each bowl coated with talcum powder to prevent bed bugs from climbing up and escaping. The inner bowl captures bed bugs hiding on the bed as they move off the bed, and the outer bowl captures bed bugs moving to the bed from other areas (Fig. 11). Use of new, improved traps may help with bed bug detection and monitoring, and when used with other strategies, may help reduce the bed bug population.
