Bed bug infestations are primarily the result of two species of insects from genus Cimex: Cimex lectularius (the common bed bug) and Cimex hemipterus. These insects feed exclusively on blood and may survive a year without eating. Adult Cimex are light brown to reddish-brown, flat, oval, and have no hind wings. The front wings are vestigial and reduced to pad-like structures. Adults grow to 4–5 mm (0.16–0.20 in) long and 1.5–3 mm (0.059–0.118 in) wide.
Blood spots found on one’s sheets, bites and the presence of bed bug feces and cast skins are some of the indications of a bed bug infestation. Bites are commonly found on the parts of the body that are more likely to be exposed to bed bugs during sleep – the hands, neck, face, shoulders, legs and arms. While not always the case, bed bug bites are often grouped together in a small area and at times may occur in a line or a zigzag pattern. Bites normally look like small, flat or raised areas that may become inflamed, itchy, red or blistered. Bed bug bite reactions don’t always appear immediately after you’re bitten and may take a few days to begin causing symptoms. However, not everyone reacts to bed bug bites in the same manner.