Bed bugs have five immature nymph life stages and a final sexually mature adult stage. They shed their skins through ecdysis at each stage, discarding their outer exoskeleton. Newly hatched nymphs are translucent, lighter in color, and become browner as they moult and reach maturity. Bed bugs may be mistaken for other insects, such as booklice, small cockroaches, or carpet beetles; however, when warm and active, their movements are more ant-like, and like most other true bugs, they emit a characteristic disagreeable odor when crushed.
Bedbugs are small, flat, wingless insects with six legs that, like mosquitoes, feed on blood from animals or people. They range in color from almost white to brown, but they turn rusty red after feeding. The common bedbug doesn't grow much longer than 0.2 inches (0.5 centimeters) and can be seen by the naked eye to the astute observer. Bedbugs get their name because they like to hide in bedding and mattresses.
Bedbugs are found all over the world. Bed bug infestations were common in the U.S. before World War II and became rare after widespread use of the insecticide DDT for pest control began in the 1940s and 1950s. They remained prevalent in other areas of the world and, in recent years, have been increasingly observed again in the U.S. Increases in immigration and travel from the developing world as well as restrictions on the use of stronger pesticides may be factors that have led to the relatively recent increase in bedbug infestations. While bedbug infestations are often reported to be found when sanitation conditions are poor or when birds or mammals (particularly bats) are nesting on or near a home, bedbugs can also live and thrive in clean environments. Crowded living quarters also facilitate the spread of bedbug infestations.
Bites on dogs and cats will look much like bites on people, and the pet owner may actually suspect a mosquito or flea bit the pet. As with people, bed bugs do not stay on pets, but return to a protected harborage site after feeding. In addition to bites, the presence of the bug’s feces, cast skins and the animal’s irritation at night are also indicators of bed bugs biting pets. Therefore, one of the best things to do is inspect the pet’s bedding and frequently groom the animal while being vigilant for the telltale signs of bed bug presence.