Bedbug infestation is the contamination of bedding, clothing, and household furnishings with the insect Cimex lectularius or C. hemipterus, commonly known as bedbugs.
Magnified image of a bedbug, which can often be found clinging to mattresses.
Before 1950, bedbugs were common worldwide. The development of the pesticide DDT eliminated bedbugs from most developed countries. However, since DDT use has been banned because of its harmful effects on the environment, bedbugs have made a comeback. Bedbug infestation is relatively common in developed countries and very common in underdeveloped countries. They spread easily, often through international travelers and are difficult to exterminate. Bedbugs are equal opportunity pests, showing no preference in the age, gender, or race of their victims.
Bedbugs are small (5-8 mm long), oval, reddishbrown insects that feed on blood of birds and mammals. They are primarily nocturnal, feeding at night. During the day, they hide in mattress seams, cracks in bed frames or other furniture, behind loose wallpaper, and in bedding and clothing. Females lay large numbers of eggs that hatch in 4-5 days. Adults can live for months without feeding.
Bedbug bites are painless, but the bites cause an allergic reaction in most people resulting in an itchy, red rash. Although bedbug bites are rarely medically dangerous, they can become infected through scratching.
People often associate bedbugs with poor or dirty living conditions, but bedbugs can be found in pristinely clean environments. In recent years, complaints about bedbugs in both budget and first-class hotels have increased.
The risk of exposure to bedbugs increases with certain activities including:
The bite of a bedbug causes an allergic reaction in most people that can be difficult to differentiate from skin reactions caused by other bites or allergies. The rash caused by bedbugs is a red, itchy rash that is typically darker in the center of the bite. Often, but not always, bites form lines or groups of three, sometimes called "breakfast," "lunch," and "dinner." Although bedbugs will bite any exposed skin, bites are most often found on the face, neck, arms, and hands.
The time it takes a bedbug rash to appear is variable, ranging from as long as 10 days to less than one minute. Generally, the more frequently a person is exposed to bedbugs, the shorter the time it takes for the rash to appear. In rare cases, some individuals can have an extreme, life-threatening allergic reaction to bedbug bites called anaphylaxis or anaphylactic shock.
Bedbugs can be infected with the hepatitis B virus and with the parasite that causes Chagas disease.
Medical diagnosis is not always necessary; the individual can make the diagnosis based on their past experience with bedbugs and recent history of travel or examination of their bedding for signs of infestation. When a medical diagnosis is sought, it is made based on the appearance of the rash along with a detailed history of recent travel and hotel stays. The doctor may also inquire about any drugs, herbs, or supplements being taken to help eliminate other possible causes of the rash. There are no tests to diagnose bedbug bites.
The symptoms and rash associated with bedbug bites go away on their own, usually within a week to 10 days. An over-the-counter skin cream containing hydrocortisone may be applied to reduce itching. An over-thecounter antihistamine containing diphenhydramine (e.g., Benadryl) may also help reduce itching. Parents of affected infants and children, or pregnant and breastfeeding women should consult an appropriate healthcare professional before using these medications.
Ridding an infested environment of bedbugs is considerably more difficult than treatment of the individual. A professional exterminator experienced with bedbug elimination may be required. Because bedbugs can hide in small cracks in furniture, mattresses, and box springs, vacuuming will not remove all of them. Special mattress covers can be purchased to lock out bedbugs, but it may be more effective to purchase a new mattress and box springs. Bedbugs can live for 9-12 months without feeding.
Bedbugs can be killed by heat. Bedding and clothing should be washed in hot water and dried at very hot temperatures. The temperature must reach at least 120 °F (49 °C). Items that cannot be washed can be put in sealed plastic bags and placed in a car with the windows rolled up in the summer when the temperature will reach 120 degrees or more inside the car. Freezing is less effective. Items must be left at temperatures below 32 °F (0 °C) for several days to kill bedbugs.
Insecticides effective against bedbugs include pemethrin and diethyltoulamide. Pemethrin spray can be used on clothing. Diethyltoluamide in high concentrations can be toxic to infants and children. Consult a physician before using. A professional exterminator is the safest way to rid the environment of bedbugs.
Room foggers and sprays against mosquitoes and ticks are ineffective against bedbugs. Many treatments for the elimination or prevention of bedbugs are sold over the Internet. These vary considerably in cost and effectiveness, so it is important to research products before buying.
Almost everyone recovers from bedbug bites within two weeks. Complications may arise from scratching the bites so that they become infected. If infection occurs, then an antibiotic may be prescribed. Very rarely do bedbug bites transmit hepatitis B or Chagas disease to humans.
Prevention is difficult. Avoiding secondhand bed frames, mattresses, and beds is helpful. Birds and bats can carry bedbugs, so they should be eliminated from attics and eaves. Checking the seams of mattresses for dark specks of bedbug excrement in hotels is helpful but not foolproof.