Bed bugs are small parasitic insects that feed on the blood of mammals and birds. Adult bed bugs have flat bodies about one-quarter of an inch in length; they are copper colored and wingless. Bed bugs do not fly; they either crawl or are carried from place to place. In homes, hotels, or other dwellings, bed bugs feed primarily on human blood, usually at night when people are sleeping.
According to the Centers for Disease Control, the United States is one of many countries now experiencing a resurgence in the population of bed bugs. Though the exact cause is not known, experts suspect the resurgence is associated with increased resistance of bed bugs to available pesticides, greater international and domestic travel, lack of knowledge regarding control of bed bugs due to their prolonged absence, and the continuing decline or elimination of effective vector/pest control programs at state and local public health agencies.
Bed bugs are not known to transmit disease. However, bed bug bites can cause large, itchy welts on the skin. The California Department of Public Health, Vector-borne Disease Section, recommends hiring a licensed pest control operator to get rid of bed bugs in the room or building where they are found.