Bed bugs are active mostly at night.
Their preferred host must be calm and unaware of their feeding. This makes a sleeping human late at night an ideal host.
Research has shown that bed bugs are most active after 3 a.m. meaning that a host who goes to bed in the late evening and rises in the early morning can be an opportune host. This is the typical sleeping habit of most Americans.
Bed bugs are not social insects, meaning that they do not have a queen or workers. They do, however, congregate in small groups or clusters. When a host is available, the scent, warmth, and carbon dioxide draw the bed bug towards the host. Late-night is prime feeding time since the host is calm after earlier restless sleep. This deep sleep period is when the host is least likely to sense bed bugs feeding. Most bed bugs can be found within five feet of a bed providing them access to humans at any time during the night.
Bed bugs are not found only in beds. Some people sleep in chairs or on sofas. This can be especially true of elderly with inconsistent sleep habits. It is common to find infestations near chairs frequented by hosts.
If a host is not home at night due to work schedules, bed bugs will feed when the host sleeps. It is not a matter of schedule, but rather a matter of opportunity. This is why bed bugs will thrive in situations where blood meals are present only during the day such as on airplanes and subways.
Bed bugs will feed for a short period of three to ten minutes. They might take more than one short meal in a feeding. Because of these short meals, hosts, even if awake, might not notice bed bugs. Moreover, young bed bugs can be nearly invisible and not obvious to those who are acting as unsuspecting hosts.