Bed Bugs

Synopsis

CAPC Recommends

• Work with a licensed exterminator to eliminate bed bug infestations in the home.

• Recognize that pets are not involved in bed bug infestations and do not serve as a source of bed bugs in the home.

• Understand that flea control products commonly used to protect pets from fleas are not labeled for bed bugs, and because bed bugs feed primarily on people, treating pets would not be expected to be an effective form of control.

Species

Cimex lectularius


Cimex hemipterus

Overview of Life Cycle

• Bed bugs live primarily in the infested home environment, emerging at night to feed on people and other animals.

• Adult bed bugs mate and females deposit eggs in the environment. The larvae that hatch from the eggs are very small (~1.5mm long) and must feed on blood before molting to the next stage.

• Each of five progressive immature stages takes a blood meal before molting.

• Both male and female adult bed bugs repeatedly feed every 3-4 days over several weeks, with females continuously depositing eggs in the environment.

• Adult bed bugs live an average of 6-12 months in the environment; unfed adults may survive for up to a year.

Stages

• Eggs – approximately 1 mm long, deposited in the environment; off-white

• Nymphs (five progressively larger stages) – approximately 1.5mm - 4.5mm unfed, slightly larger upon feeding; light yellow to dark brown color

• Adults – 5.5mm long when unfed, increasing in weight and length upon feeding; red-brown color

Disease

• Feeding by bed bugs elicits distinct erythematous pruritic lesions at the feeding site. Bed bug bites are generally not painful, but the pruritic lesions produced disrupt sleep and can cause anemia, particularly in children in heavily infested environments.

• Not everyone bitten by bed bugs will develop lesions, which sometimes results in delayed identification of the presence of the bed bugs in a given environment.

• Bed bugs also often affect the mental health of people who discover the infestations, including increased anxiety and insomnia.

• Bed bugs are not known to transmit any human or animal disease agents. Occasionally, human blood-borne pathogens have been detected in fed bed bugs but vector competency studies failed to demonstrate that transmission actually occurs.

Prevalence

• Cimex lectularius is the common bed bug found throughout the United States, Canada, and most of the developed world.

• In the United States, reports of premises infested with Cimex lectularius have increased dramatically in recent years, widely thought due to development of insecticide resistance, changes in pest control practices, and increased international travel.

• Reports are particularly common in shared housing facilities that experience frequent resident turnover such as hotels, university dormitories, hospitals, and homeless shelters, although bed bugs are also frequently reported from apartments and single-family homes.

Host Associations and Transmission Between Hosts

• Bed bugs primarily feed on people, and infestations are always associated with human habitation. However, bed bugs may also feed on dogs and cats when pets are present in an infested home.

• Bed bug infestations are introduced to homes in luggage, clothing, used furniture, backpacks, book bags, or similar objects when they are transported from an infested premise into the home.

• Bed bugs may also move between hotel rooms and apartments through air ducts or other shared conduits.

• Although theoretically possible for bed bugs to be transported into a home on a pet or in pet bedding, pets are considered an unlikely route for introducing the pests.

Environmental Factors

• Bed bugs avoid light, hiding in dark areas near where hosts routinely sleep at night, including in mattress seams and inside box springs, behind headboards, and under baseboards and behind loose wallpaper.

• When bed bugs become active at night, they seek warmth from a nearby host on which to feed.  Every stage of the bed bug must feed on blood to molt to the next stage, and adults repeatedly feed and deposit eggs in the environment.

• Bed bugs in dark environments, such as movie theaters, may also be active and feed during the day.

Diagnosis

• In general, because the bite of a bed bug is painless and the pests feed primarily at night, infestations are first suspected when people sleeping in the infested area develop the red, pruritic welts characteristic of an allergic reaction to the feeding bugs.

• In some patients who become sensitized to the bed bugs, the reaction increases with repeated bites, and more severe wheals, diffuse urticaria, nodules, and, rarely, anaphylaxis may develop.

• Close inspection of the bed and immediately surrounding environment will usually reveal evidence of immature and adult bed bugs, casts (shed exoskeletons) from previous molts, and frass, the bed bug feces which appears as small round black flecks in the environment.

• Areas harboring bed bugs often develop a distinct sweet, musty odor.

Treatment

• Bed bug infestations are usually managed by licensed pest control operators who are trained in treating homes with bed bugs.

• Once bed bugs are confirmed in the home, a pest control company will treat the premise using either environmentally applied pesticides or heat treatment. Pets should be removed during application of treatment. Repeated treatments may be necessary to eliminate the infestations.

• The pest control company can also provide advice about cleaning bedding and upholstered materials to eliminate the bed bugs.

• When pets are present, their bedding should be laundered using hot (>120F) water and high heat in the dryer. If a pet bed is torn or has holes preventing thorough cleaning, the bedding should be discarded.

• Premise sprays containing insecticides such as imidacloprid are also available for treating bed bugs and may be of value in managing some home infestations.

Control and Prevention

• Avoid bringing used furniture of unknown origin into the home; inspect all purchased used furniture closely to be sure bed bugs are not present.

• When staying in a hotel, closely inspect the bed, surrounding area, and other furniture upon arrival, and store any suitcases off the floor and bed. A folding suitcase rack is mandated in all hotel rooms in the United States for this purpose. When returning from a premise that may harbor bed bugs, store any suspected, exposed clothing or suitcases in a sealed plastic bag until it can be washed or closely inspected and cleaned, respectively.

• Seal cracks and crevices with caulk to prevent movement of bed bugs between housing units.

• Flea control products commonly used to protect pets from fleas are not labeled for bed bugs. In addition, because the bed bugs feed primarily on people, treating pets would not be expected to be an effective form of control.

Public Health Consideration

• Bed bugs are primarily a parasite of people, living in areas inhabited by or frequented by the human hosts they require for their blood meal and development.

• Although some studies report detection of human blood-borne pathogens in bed bugs after feeding on infected people, these pests have not been found capable of transmitting any human disease agents to date.

Selected References

• Anderson A, Leffler K. 2008. Bed bug infestations in the news: a picture of an emerging public health problem in the United States. J Environ Health 70(9):24-7.

• American Veterinary Medical Association. Public Resources: Pet care. 2012. Bed bugs and pets FAQ. http://www.avma.org. Accessed March 1, 2013.

• CDC/EPA. 2010. Joint statement on bed bug control in the United States from the U. S. Centers for Disease Control and Prevention (CDC) and the U. S. Environmental Protection Agency (EPA). Atlanta. U.S. Department of Health and Human Services. www.cdc.gov. Accessed March 1, 2013.

• Goddard J, deShazo R. 2009. Bed bugs (Cimex lectularius) and clinical consequences of their bites. JAMA 301(13):1358-1366.