Bed bugs are parasitic insects that feed on the blood of hosts, often times without being noticed, and are mainly active at night. The name "bed bug" comes from the insect’s affinity for infesting beds or other areas where people sleep. Bed bugs have been pests to humans for thousands of years. They were mostly eradicated from the United States in the 1940’s, but we have seen an increase in the number of infestations in recent years. Adult bed bugs have flattened oval shaped bodies and are a light brown color. They can grow to 4–5 mm in length and 1.5–3 mm wide. Nymphs are translucent and lighter in color.