Bed bugs are flat, oval, almost wingless (wings represented by small stubs), parasitic insects that feed exclusively on blood.
The adults are reddish-brown and usually less than a quarter-inch long. They can run with surprising speed, and at night, they hunt for sleeping mammals (humans, rats, mice or rabbits) or birds in order to obtain a blood meal. They have been associated with humans for thousands of years, and they were brought to North America by the early colonists.
Their preferred habitat is a warm building and especially near or inside beds and bedding or other sleep areas. Bed bugs tend to tend to be active mainly at night, but they are not exclusively nocturnal. They prefer exposed skin, preferably the face, neck and arms of a sleeping person, and they usually feed on their host without being noticed.
The modified mouth parts of a bed bug can saw through the skin of its host and inject saliva with anticoagulants and an array of special proteins that block the host’s pain sensations. Pressure from a pierced blood vessel can fill the insect with blood in about three to five minutes Usually, it will not feed again until it has either completed a molt or, if an adult, has thoroughly digested the meal.
In the early 1940s, bed bugs had decreased in prevalence throughout most of the developed world, but since 1955, they have become more of a problem pest again even in the best of homes, inns, motels and hotels. This is most likely due to a combination of pesticide resistance and governmental bans on the most effective pesticides.
Fortunately, bed bugs are not known to transmit any human diseases, but their bites can cause a number of adverse health effects, such as skin rashes, psychological effects and allergic symptoms.
Bed bugs can be used as forensic evidence at a crime scene. DNA from a human blood meal can be recovered from them for up to about 90 days, identifying on whom the bed bugs have fed. Maybe you can figure out a way to weave this fact into your next mystery novel.