L-1742

BED BUGS

by Harry Howell

    Bed Bugs, generally called "chinches" in Texas, feed on blood , principally that of man, by piercing the skin with their elongated beak. It never has been proven that bed bugs are carriers of disease causing pathogens in the U.S. Bed bugs are spread chiefly by clothing and baggage of travelers and visitors, secondhand beds, bedding, furniture and laundry.

IDENTIFICATION

    The mature bed bug is a dark brown, wingless insect. Its size depends on the amount of blood that the body contains. An unfed bed bug is between 1/4 and 3/8 inch long. The upper surface of the body has a flimsy, crinkly appearance.

    When engorged with blood, the body becomes elongated and swollen, and the color changes from brown to dull red. The change in size, shape and color is remarkably difference from that of an unfed bed bug.

Figure 1: Mature bed bug before engorgement.  Drawing is approximately six times actual size.

Figure 2: Mature bed bug after engorgement with blood (shows distention of body and altered appearance).

     Bed bug eggs are white and about 1/32 inch long. Newly hatched bugs are translucent and nearly colorless. Young bugs are similar in shape to the adults. As they grow, they molt (shed their skins). After each molt they are pale in color, then become brownish.

BIOLOGY AND HABITS

    Under favorable conditions of temperature (above 70N F) and regular feeding, female bed bugs will lay about 200 eggs during her lifetime at the rate of 3 or 4 per day. Eggs are coated with a sticky substance, causing them to adhere to objects on which they are deposited. The eggs hatch in 6 to 17 days and the nymphs begin to feed on blood immediately. After 5 molts, bed bugs reach maturity. There may be 3 or more generations a year. Environmental factors and the availability of food will cause considerable variation in the developmental rate of all stages of growth. Young and old bed bugs may live for several weeks to several months without feeding, depending upon the temperature.

    Bed bugs feed mostly at night, by piercing the skin of people as they sleep. However, if they are very hungry and if the light is dim, they will feed during the day.

    When bed bugs bite, they inject a fluid into the skin that assists them in obtaining blood. Often the fluid causes the skin to become irritated , inflamed and to itch. Elongated, spindle shaped welts develop as a result of the bite. If the bites are on the limbs (arms or legs), these welts will be aligned with the long axis of the limb. This elongated, spindle shape distinguishes the welts from those resulting from mosquito or flea bites. .

    If its feeding is undisturbed, a full grown bed bug becomes engorged with blood in 3 to 5 minutes. It then crawls to its hiding place, where it remains for several days digesting its meal. When hunger returns, the bug emerges from hiding and seeks another meal of blood.

    Habitual hiding places are evident by black or brown spots of dried excrement on surfaces on which the bugs rest. Eggs, egg shells and cast skins also may be seen near these places. There usually is an distinctive odor in rooms where bed bugs are numerous.

    At the beginning of an infestation in a room, bed bugs are likely to be found only about the turfs, seams and folds of mattresses and covers; later they spread to crevices in the bedsteads.

    If allowed to multiply, they establish themselves behind baseboards, window and door casings, pictures and picture moldings, and in furniture, loosened wallpaper, cracks in plaster and partitions.

CONTROL

    To control bed bugs in homes, locate their hiding places such as described above and treat with an insecticide approved for this use. Select a product whose label includes specific directions for bed bug control. Spray or dust beds (slats, springs and frame) and other hiding places about the room.

    Do not use any insecticide on a mattress unless the product label specifically gives directions for this use. Apply a light application to the entire surface of the mattress and as a crack and crevice application along the seams, turfs and folds. Allow 1 to 2 hours for treated surfaces to dry prior to use.

    Because it is impossible to penetrate all hiding places, control is usually not immediate. A few living bugs may be seen for a week to 10 days after application. After 10 days, a second application, equal to the first is necessary to kill the just hatching nymphs. The pesticides used for bedbug control have a short residual life and so this second application is always needed. For heavily infested areas, it is recommended that a commercial pest control operator be consulted to control the infestation.

    Insecticide label clearances are subject to change and changes may have occurred since this publication was printed. The pesticide USER is always responsible for the effects of pesticides on his own plants or household goods as well as problems caused by drift from his property to other properties or plants. Always read and follow carefully the instructions on the container label.

The information given herein is for educational purposes only. Reference to commercial products or trade names is made with the understanding that no discrimination is intended and no endorsement by the Cooperative Extension Service is implied.

Educational programs conducted by the Texas Agricultural Extension Service are open to all people without regard to race, color, sex, disability, religion, age or national origin.

Issued in furtherance of Cooperative Extension Work in Agriculture and Home Economics, Acts of Congress of May 8, 1914, as amended, and June 30, 1914, in cooperation with the United States Department of Agriculture. Zerle L. Carpenter, Director, Texas Agricultural Extension Service, The Texas A&M University System.

ENT

Return to top of page

Return to Departmental Home Page

Last modified: August, 2001 by A. Paulson