Bed bugs may be mistaken for other insects, such as booklice, small cockroaches, or carpet beetles; however, when warm and active, their movements are more ant-like, and like most other true bugs, they emit a characteristic disagreeable odor when crushed. Bed bugs are obligatory bloodsuckers. They have mouth parts that saw through the skin and inject saliva with anticoagulants and painkillers. Sensitivity of humans varies from extreme allergic reaction to no reaction at all (about 20%). The bite usually produces a swelling with no red spot, but when many bugs feed on a small area, reddish spots may appear after the swelling subsides. Bedbugs prefer exposed skin, preferably the face, neck, and arms of a sleeping person. Bed bugs are attracted to their hosts primarily by carbon dioxide, secondarily by warmth, and also by certain chemicals. There is strong evidence that bed bugs can respond and orient towards human odors, independently of all other host cues. Cimex lectularius feeds only every five to seven days, which suggests that it does not spend the majority of its life searching for a host. When a bed bug is starved, it leaves its shelter and searches for a host. It returns to its shelter after successful feeding or if it encounters exposure to light. Cimex lectularius aggregate under all life stages and mating conditions. Bed bugs may choose to aggregate because of predation, resistance to desiccation, and more opportunities to find a mate. Airborne pheromones are responsible for aggregations. Spread
Infestation is rarely caused by a lack of hygiene.
References
External links

Bed bug on the University of Florida/IFAS Featured Creatures Web site
National Geographic segment on Bed bugs on YouTube
Bed bugs – University of Sydney and Westmead Hospital Department of Medical Entomology
Understanding and Controlling Bed Bugs – National Pesticide Information Center
CISR: Center for Invasive Species Research More information on Bed Bugs, with many photos and video
EPA bedbugs information page
A Code of Practice for the Control of Bed Bugs in Australia, ICPMR & AEPMA, Sydney Australia, September 2011. ISBN 1-74080-135-0. "Bed Bug Home Page". Bedbug.org.au. 14 October 2005. Retrieved 11 November 2013.