Color enhanced bedbug (Cimex lectularius) illustration. Bed bugs are not vectors in nature of any known human disease. The common bed bug is found worldwide. Infestations are common in the developing world, occurring in settings of unsanitary living conditions and severe crowding. In North America and Western Europe, bed bug infestations became rare during the second half of the 20th century and have been viewed as a condition that occurs in travelers returning from developing countries. However, anecdotal reports suggest that bed bugs are increasingly common in the United States, Canada, and the United Kingdom. The common bed bug C. lectularius is a wingless, red-brown, blood-sucking insect that grows up to 7 mm in length and has a lifespan from 4 months up to 1 year. Bed bugs hide in cracks and crevices in beds, wooden furniture, floors, and walls during the daytime and emerge at night to feed on their preferred host, humans.