Bed bugs are parasitic insects of the cimicid family that feed exclusively on blood. The term most commonly refers to members of the genus Cimex of which Cimex lectularius, the common bed bug, is the best known as it prefers to feed on human blood although other Cimex species are specialized to other animals, e.g., bat bugs, Cimex pipistrelli (Europe), Cimex pilosellus (western US), and Cimex adjunctus (entire eastern US).
The name of the “bed bug” is derived from the preferred habitat of Cimex lectularius: warm houses and especially nearby or inside of beds and bedding or other sleep areas. Bed bugs are mainly active at night, but are not exclusively nocturnal. They usually feed on their hosts without being noticed.
A number of adverse health effects may result from bed bug bites, including skin rashes, psychological effects, and allergic symptoms. Diagnosis involves both finding bed bugs and the occurrence of compatible symptoms.
Bed bugs have been known as human parasites for thousands of years. At a point in the early 1940s, they were mostly eradicated in the developed world, but have increased in prevalence since 1995. Because infestation of human habitats has been on the increase, bed bug bites and related conditions have been on the rise as well.
Dwellings can become infested with bed bugs in a variety of ways, such as:
- Bugs and eggs inadvertently brought in from other infested dwellings on a visiting person’s clothing or luggage;
- Infested items (such as furniture, clothing, or backpacks) brought in;
- Nearby dwellings or infested items, if easy routes are available for travel (through duct work or false ceilings);
- Wild animals (such as bats or birds) that may also harbour bed bugs or related species such as the bat bug;
- People visiting an infested area (apartment, subway, movie theatre, or hotel) and carrying the bugs to another area on their clothing, luggage, or bodies.
Though bed bugs will feed on pets, they do not live or travel on the skin of their hosts, and pets are not believed to be a factor in their spread.