Acknowledgement: Some of the material in this article is being used with permission of Harvard University
Not long ago bed bugs were considered has beens of the pest world. Now, however, in the wake of restrictrions on the most powerful pesticides, increased travel, and urban congestion, bed bugs have made a serious comeback. In this article we consider the phenomenon of bed bug return, and we will look at the life style and life cycle of this ubiquitous pests.
Bed bugs are part of the insect family Cimicidae. There are three Cimicidae species that feed on people. The most common bedbug one found in human infestations is Cimex lectularius. Bedbugs may feed on any type of warm blooded mammal, including bats, birds, and rats.
Cimex lectularius is most often seen in the northern temperate climates of North America, Europe, and Central Asia and is most adapted for city dwelling areas. It is found more sporadically in southern temperate regions. In Florida and tropical locales it is replaced by C. hemipterus. At one time, as a result of effective insecticides such as DDT, bedbug infestations were greatly diminished in number. In recent years, however, because of the ban on the most powerful insecticides, greater urban congestion and the increase in international travel, they have made a comeback.
IDENTIFICATION AND LIFE CYCLE
Mature bed bugs have no wings and are 1/5 inch long oval rusty red or mahogany in color. Bed bug bodies are very thin and have long antennae. Bedbug eyes are small, and the area behind their head puffs out on either side giving the appearance of a renaissance ruff collar. Immature bedbugs appear identical to adults except for their size, thinner cuticle, and a lighter, yellowish white color. Bed bugs are readily distinguished from kissing bugs, the vector of Chagas disease by their smaller size, more rounded shape, and lack of wings as adults.
Bed bugs can multiplying rapidly, and even a single pregnant female can infest a home. A single fertilized female lays anywhere from 200 to 500 eggs (in batches of 10 to 50). They lay their eggs in very readily available places including rough surfaces such as wood or paper. Bed bug eggs are covered with a sticky substance and hatch in about 10 days. Even after the eggs hatch, the shells frequently remain on the substrate.
Subsequently, bed bugs pass through five nymphal stages of growth. Characteristically, the nymphs require a single blood meal before molting to the next stage. The entire life cycle from egg to adult stretches over a span of time lasting anywhere from 5 weeks to 4 months, depending on temperature. Bed bugs develop more quickly in a warm climate with thermometer readings ranging from 72 to 80 degrees. Both nymphs and adults most commonly take their blood meal at night and hide in crevices during the day. Common hiding places include mattresses and box spring seams, cracks in bed frames, spaces behind loose wallpaper, backs of picture frames, and insides of furniture fabric coverings.
Bed bugs can live for 80 to 140 days without any nourishment; more mature ones can live longer without feeding than younger ones. Adult bed bugs have continued without nutrition for as long as 550 days. A bed bug can ingest six times its weight in blood, and their meals can extend 3 to 10 minutes. They generally live about 10 months and can produce up to 3 or 4 generations of oppspring in the course of a year.
Bed bugs may be picked up in theaters, on buses and trains, and subsequently brought into homes on clothing, bedding, luggage, or even firewood. Additionally, although much less commonly, bed bugs that feed on other mammals and birds (chickens, mice, rats, and rabbits) that live near the home may under some circumstances feed on humans if, for example, their primary hosts disappear.