Bed bugs are in the insect family Cimicidae and include three species that attack people. Of these, the most important is Cimex lectularius, which may also bite bats, birds, and rodents. Until recently, bed bug infestations were thought to be associated primarily with crowded and dilapidated housing. However, such infestations have undergone a resurgence and can be found even in the finest hotel and living accommodations. The reasons for the resurgence are not totally understood but appear to involve increased human travel, ease of movement of infested luggage and items, and changes in the pesticides available to control this pest.