> Table of Contents > Bed Bugs
Bed Bugs
Fawn Winkelman, DO
Adam Strosberg, DNP, ARNP-BC
image BASICS
DESCRIPTION
  • Nocturnal obligate blood parasites that take refuge on furniture and bedding
  • 5 to 7 mm oval, reddish brown, flat, wingless
EPIDEMIOLOGY
Incidence
  • According to the 2013 “Bugs Without Borders” survey, bed bug infestations are increasing and continue to remain the most difficult pest to treat, more difficult than cockroaches, termites, and ants (1)[B].
  • Resurgence is due to the use of less toxic, less persistent insecticides as well as increased travel, use of secondhand furniture, and a high-turnover rate of residents in hotels.
Prevalence
  • Infestations are increasing across the United States.
  • Sharp increase in prevalence, as only 11% of survey respondents reported bed bug calls >10 years ago.
  • Bed bug encounters have become more common in public places (schools, hospitals, hotels/motels, aircrafts) than in previous years, increasing by 10-30% (2)[B].
ETIOLOGY AND PATHOPHYSIOLOGY
  • Insect family Cimicidae
  • Three species that bite humans: Cimex lectularius, Cimex hemipterus, and Leptocimex boueti (2)[B]
  • Most prevalent species are the C. lectularius (2)[B].
  • Found in tropical or temperate climates
  • Hide in crevices of mattresses, box springs, headboards, and baseboards
  • Infestations occur in hotels/motels, hospitals, cinemas, transportation vehicles, aircrafts, and homes.
  • Reactions range from an absent or minimal response to a more typical reaction presenting as pruritic, erythematous macules and papules or a less common urticarial and anaphylactic response.
  • Skin reactions are due to host immunologic response to the parasite salivary proteins.
  • Papular urticarial reactions are mediated via immunoglobulin (Ig) G antibody response to salivary proteins (3)[B].
  • Bullous reactions are caused by an IgE-mediated hypersensitivity to nitrophorin, the substance that transports nitric oxide in bed bug saliva (3)[B].
  • Bed bugs locate warmth and carbon dioxide production, which allows them to migrate to humans (4).
GENERAL PREVENTION
  • Bed bug monitors and traps can be purchased, which contain carbon dioxide as well as heat to attract and trap the bugs but can be cost-prohibitive (5)[B].
  • Avoidance of bed bugs: vacuum regularly, reduce clutter, seal cracks in walls, inspect luggage and clothing
  • Launder all bedding and cloth items in 130°F (50°C) or hotter for 2 hours or 20°F (−5°C) or cooler for 5 days.
  • If present in the home, eradication is essential via professional extermination. Some pest control companies have employed pest control canines to detect live bed bugs and eggs based on pheromones from the bed bugs but are expensive and generate false positives and negatives depending on the training of the dog (5)[B].
RISK FACTORS
  • Immunologically weak or compromised
  • Recent travel
  • High turnover environment
  • Secondhand furniture in home
image DIAGNOSIS
PHYSICAL EXAM
  • Characteristic lesions are erythematous pruritic papules in an irregular linear pattern.
  • Found on body surfaces exposed during sleeping such as face, neck, arms, legs, and shoulders
  • May appear hours to days after being bitten
  • Patients are usually asymptomatic but may be anaphylactic and present with papular urticaria, diffuse urticaria, and/or bullous lesions.
DIFFERENTIAL DIAGNOSIS
  • Urticaria
  • Insect or spider bite
  • Scabies
  • Dermatitis herpetiformis
DIAGNOSTIC TESTS & INTERPRETATION
Initial Tests (lab, imaging)
  • Skin scraping with mineral oil preparation
  • Skin biopsy
Test Interpretation
  • Skin scraping is negative with mineral oil, which helps to exclude scabies.
  • Skin biopsy shows nonspecific perivascular eosinophilic infiltrate consistent with arthropod bite reaction.
P.117

image TREATMENT
GENERAL MEASURES
  • Self-limited and resolves within 1 to 2 weeks
  • Treat symptomatically
  • Avoidance of the bed bugs by inspection
  • Prevention by laundering bedding and cloth
MEDICATION
First Line
  • Disease is self-limited; treat symptoms.
  • Oral antihistamines (i.e., diphenhydramine, hydroxyzine)
  • Topical antipruritics (i.e., pramoxine/calamine ointment or doxepin cream)
  • Topical low to midpotency corticosteroids for 2 weeks (i.e., hydrocortisone, triamcinolone)
  • Systemic corticosteroids (severe cases)
ADDITIONAL THERAPIES
  • If secondarily infected, use topical or oral antibiotics against Staphylococcus and Streptococcus spp. (i.e., cephalexin, tetracycline, doxycycline, clindamycin, topical mupirocin).
  • Epinephrine for anaphylaxis
  • Professional extermination may be necessary.
image ONGOING CARE
FOLLOW-UP RECOMMENDATIONS
  • Not necessary as disease is self-limited
  • Recommended in extreme cases or if anaphylaxis ensues
PATIENT EDUCATION
  • Avoid scratching to prevent superinfection.
  • Inspect bedding, furniture, and luggage regularly.
  • CDC: http://www.cdc.gov/parasites/bedbugs/
  • EPA: http://www2.epa.gov/bedbugs
  • MYTH 1: Bed bugs are invisible. They actually are nocturnal and hide during the daytime and adult bugs are about 1/4-inch long while eggs are the side of a pin head (6).
  • MYTH 2: Bed bugs reproduce rapidly. Their life cycles are about 4 to 5 weeks (6), which is longer than the typical house fly.
  • MYTH 3: Bed bugs can live without feeding. Bugs can only live about 3 to 5 months without a blood meal depending on climate (6).
REFERENCES
1. Studdiford JS, Conniff KM, Trayes KP, et al. Bedbug infestation. Am Fam Physician. 2012;86(7):653-658.
2. Kolb A, Needham GR, Neyman KM, et al. Bedbugs. Dermatol Ther. 2009;22(4):347-352.
3. Goddard J, deShazo R. Bedbugs (Cimex lectularius) and clinical consequences of their bites. JAMA. 2009;301(13):1358-1366.
4. Williams K, Willis MS. Bedbugs in the 21st century: the reemergence of an old foe. Lab Medicine. 2012;43:141-148.
5. Vaidyanathan R, Feldlaufer MF. Bed bug detection: current technologies and future directions. Am J Trop Med Hyg. 2013;88(4):619-625.
6. Ogg B. Bed bug myths—rely on research for facts. The Nebline, University of Nebraska-Lincoln Extension. 2012;347-348.
Additional Reading
  • Lancaster Extension Education Center at http://lancaster.unl.edu/pest/bugs.shtml
  • The National Pesticide Information Center (NPIC) 1-800-858-7378 or email at [email protected]
  • Thomas I, Kihiczak GG, Schwartz RA. Bedbug bites: a review. Int J Dermatol. 2004;43(6):430-433.
Codes
ICD10
  • S00.96XA Insect bite (nonvenomous) of unspecified part of head, initial encounter
  • S10.96XA Insect bite of unspecified part of neck, initial encounter
  • S40.269A Insect bite (nonvenomous) of unspecified shoulder, initial encounter
Clinical Pearls
  • 90% of infestations occur within 3 feet of beds.
  • Wash bedding/clothing regularly in hot water.
  • Vacuum carpet daily or steam clean daily.
  • Inspect furniture, bedding, and luggage regularly.
  • Use professional services if necessary.
  • Patient education and vigilance is paramount for bed bug prevention and avoidance.
  • Over-the-counter (OTC) products that contain pyrethroids are ineffective at killing bed bugs as they have become resistant over the years. These products can be identified with a suffix “-thrin” including permethrin, cyfluthirin, bifenthrin, and deltamethrin or fluvalinate and esfenvalerate (6).