Bed Bug Habits and History
By Dr. Barry Galitzer, MD, Dermatologist
November 26th, 2009
The bed bug is an insect of the family Cimicidae. All Cimicidae are blood-sucking ectoparasites of mammals or birds. It is thought that Cimicidae adapted to feeding on humans when cave dwellers took up residence near bats. Cimex lectularius (the common bed bug) is found throughout Europe, North America, North Africa, North India, Siberia, North China, South Africa, Australia, and South America.
Adult bed bugs are reddish-brown, flat, oval bodied, wingless, with microscopic hairs that give them a banded appearance. They range in size from 5 to 7 mm and are easily visible with the naked eye. Females are slightly longer than males. Female bed bugs deposit their pearly white, flask shaped eggs in the crevices of floors and walls, in furniture, bed frames, and mattresses. The eggs, which are 1 mm in length, are already fertilized and partially developed when they are laid. They hatch in 4 to 5 days.
Bed bugs are nocturnal, with a peak feeding period about an hour before sunrise. This is when most bed bug bites occur. They avoid light, hiding in cracks and crevices or behind peeling paint. They respond to warmth and carbon dioxide (i.e., they are attracted to warm, sleeping, breathing bodies). The face, extremities, and areas uncovered by sleeping clothes or blankets, are preferentially involved. When feeding, the bed bug grasps the skin with its forelegs, pierces the skin, and injects its saliva containing an anticoagulant and an anesthetic.
What do Bed Bug Bites Look Like?
Bed bug bites present as painless but itchy red raised bumps, which may appear indistinguishable from mosquito bites. The bites are often in a linear group of three (sometimes referred to as “breakfast, lunch, and dinner”). In the individual not sensitized by a previous exposure no symptoms aside from the red spot that indicates the site of the bite may be noted. In the sensitized person irritated red bumps surmounted by a red dot in the center are the characteristic reaction. In severe reactions large blisters may develop. Bed bugs have been studied to determine if they are a vector for disease. Although Human Immunodeficiency Virus (HIV) was detected in bed bugs up to 8 days after ingesting a highly concentrated amount of the virus in a blood meal, actual transmission of the virus is unlikely. hhh Hepatitis virus is not effectively transmitted by the bed bug either.
Webb PA, Happ CM, Maupin GO, Johnson BJ, Ou CY, Monath TP. Potential for insect transmission of HIV: experimental exposure of Cimex hemipterus and Toxorhynchites amboinensis to human immunodeficiency virus. Journal of Infectious Disease1989 Dec;160(6):970-7. Kolb A, Needham GR, Neyman KM, High WA. Bed bugs. Dermatologic Therapy 2009 Jul-Aug;22(4):347-52.