Mark K. Huntington, MD, PhD When bed bugs bite Sioux Falls Residency Program; Department of Family Treating bites is straightforward; helping Medicine, University of South Dakota Sanford patients control and even prevent future is School of Medicine, Vermillion, SD another matter. Here’s how you can help. mark.huntington@usd. edu

The author reported no ed bugs, spp, are a re-emerging public health potential conflicts of interest relevant to this article. Practice problem in the United States. First recorded by the recommendations B ancient Greeks,1 bed bugs have plagued societies for › Provide symptomatic relief centuries. In the United States, infestations peaked in inten- for bed bug bites with antihis- sity in the 1920s and 1930s, then were largely eliminated as tamines or . C a significant concern after World War II, thanks to synthetic, › Advise patients experienc- residual .2 By the mid-1990s, bed bugs were so un- ing an to consider common that specimens could not be obtained for medical the CDC’s recommended education purposes.3 integrated manage- That has all changed. ment program (eg, heat Although commonly perceived as disproportionately treatment, vacuuming, affecting the underprivileged,4 bed bugs are equal- nonchemical pesticides) to opportunity pests, infesting the most posh hotels, retailers, increase the likelihood of and theaters.5,6 According to one news report summariz- successful extermination. C ing data from a national firm, US cities with the Strength of recommendation (SOR) highest infestation rates are, in descending order: Cincinnati, A Good-quality patient-oriented Columbus, , Denver, Detroit, Washington DC, New evidence York, Philadelphia, Dayton, and Baltimore.7 Although bed B  Inconsistent or limited-quality patient-oriented evidence bugs are not known to transmit infectious diseases, they are C  Consensus, usual practice, responsible for significant dermatitis, allergic reactions, and opinion, disease-oriented evidence, case series psychological distress.

Bed bug biology and behavior The bed bug life cycle has 7 stages. All but the egg stage re- quire meals before the can molt to the next stage. Bed bugs are attracted to their hosts by body heat and exhaled , and they feed only through the skin. This makes baiting and trapping challenging, although it’s a common extermination strategy for other domestic pests. Also, unlike , , or other pests, bed bug infesta- tions are not associated with hygienic deficiencies. Improved housekeeping does not significantly affect their populations; bed bugs feed on household inhabitants, not their spilled or improperly stored food. However, clutter does increase their chances of finding refuge. Interestingly, researchers recently discovered that bed bugs are themselves hosts to the endosymbiotic bacterium,

384 The Journal of Family Practice | July 2012 | Vol 61, No 7 Wolbachia.8,9 This genus is found in many more likely due to scratching. Bed bug bites invertebrates and appears to be essential for are allergenic, and they have also been impli- normal bed bug fertility and reproduction. cated in exacerbations and even ana- Targeting the may inhibit the ability phylaxis.10,11 In severe infestations, of bed bugs to breed—something we’ll dis- from the extensive blood-meals can occur.12 cuss a bit later. Experimental studies have found that >45 human —ranging from viruses to methicillin-resistant Staphylococcus au- Clinical assessment reus to helminths—can survive ingestion by Patients with bed bug bites complain about bed bugs, but none have shown pathogens intensely pruritic lesions. These are typically to be transmitted to humans by bed bugs.11 erythematous and indurated and may be hem- Fortunately, bed bugs do not appear to be orrhagic. The pattern of bites is often linear, competent as vectors, although prospective and 3 bites in a row are common, sometimes studies are ongoing.13 In addition to allergic referred to as “breakfast, lunch, and dinner.” manifestations, bed bug bites have been as- Patients typically have no recollection of being sociated with significant, even incapacitating, bitten, as bed bugs feed on sleeping hosts, and psychiatric problems such as anxiety, obses- their bite is usually painless. sion, and depression to the point of suicide.14 z Clues to bed bugs as the source. Sca- The CDC bies mites also cause linear pruritic lesions, recommends but bed bug lesions differ in appearance and Treating symptoms and cause an integrated distribution. lesions are subtle, ap- Management of bed bugs consists of symp- approach pearing as burrows and excoriations, in con- tomatic treatment of the bites and elimina- to fighting trast to the more prominent erythematous tion of the infestation—treating both patients infestation: 15 papule seen with bed bugs and other arthro- and their environments. removing clutter, pod bites. Scabies tend to occur in skin folds, sealing cracks finger webbing, genitals, and areas where Treating patients and crevices, clothing is tight, such as beltlines. In contrast, Treating bed bug bites mainly involves pro- applying heat bed bugs tend to attack easily accessible, ex- viding symptomatic relief with antipruritic treatment, posed areas. Areas covered with loose cloth- agents (, topical or oral cor- vacuuming, ing are less affected, and areas covered by ticosteroids, over-the-counter topical an- and using 16 tight clothing are essentially spared. Multiple esthetics). When, rarely, a bite becomes pesticides. members of the household are often affected. infected, antibiotics may be indicated. Ad- z bite? Bed bug bites may be virtu- dress psychological distress associated with ally indistinguishable from those of other an infestation. Counseling with cognitive be- such as , spiders, or mosqui- havioral therapy is effective most of the time, toes. While the linear 3-bite pattern may although some cases may warrant short-term suggest bed bug exposure, it is not patho­ psychopharmacotherapy. gnomonic. Capturing the arthropod or find- Symptomatic relief will be short-lived, ing evidence of infestation (discussed in a bit) however, without remediation of the underly- is needed to confirm a bed bug as the source ing infestation. If the bugs remain, the of the bite. will continue. The etiology of pruritic papules is broad. Besides arthropod bites, include conditions Treating the environment such as papular eczema, papular pruritic Every object and location in which bed bugs eruption, and eosinophilic folliculitis in the may have taken refuge must be treated. The . first step in eradicating an infestation is to find it. In light infestations, evidence may be Potential for complications limited. However, they are dirty bugs. Sig- As with any break in the skin, secondary in- nificant amounts of litter, including molted fection is a risk, although it is rarely a com- exoskeletons, dark feces, and eggs, are found plication of the bite. If occurs, it is wherever there is an infestation. These signs

jfponline.com Vol 61, No 7 | July 2012 | The Journal of Family Practice 385 TABLE Xenointoxication with has proven effective against several ectoparasite infestations24-28 In vitro research has shown that bed bugs are also susceptible to this class of antiparasitic drugs.

Ectoparasite Condition Ivermectin dosing Scabies 0.2 mg/kg, single dose Pediculus capitis Head lice 0.2 mg/kg every 10 days x 2 doses Pediculus corpora Body lice 0.2 mg/kg every 7 days x 3 doses

of infestation may be found on z Desiccant dusts such as silica gel and or box springs, or in the bottom of bureau , applied along the base- drawers and the corners of rooms. Anywhere boards and the back of bookshelves, have just out of reach of the vacuum cleaner can also demonstrated efficacy.23 As with chemi- harbor their detritus. Some success has been cal pesticides, it is important to follow direc- reported using bed bug detectors/monitors.17 tions when using desiccant dusts to minimize Bed bugs are Bed bug-sniffing have been trained and potential health hazards. good at hiding employed in both identifying infestations z The CDC recommends a comprehen- and can survive and monitoring the efficacy of eradication sive, integrated pest management program for up to a year interventions. to control bed bugs. This program includes a without feeding. A number of extermination methods number of methods, such as removing clut- have been used. The most commonly used ter and sealing cracks and crevices where chemicals are permethrins, the same agents bed bugs take refuge, applying heat treat- that have proven effective in antimalarial bed ment, vacuuming, using nonchemical pes- net programs. This agent is applied to the en- ticides, and cautiously applying effective vironment, not to the patient. Generally, at chemical pesticides.17 An approach such as least 2 applications are required. Although this is labor- and time-intensive, and can be as recently as 1990 no bed bug resistance to costly. permethrin had been reported,18 there is now Given the inadequacies of current strat- widespread resistance.19 Efforts at developing egies in controlling infestations, new ap- new agents are progressing. proaches are needed. One such approach Besides resistance, toxicity to humans is a may be xenointoxication, in which patients concern. The Centers for Disease Control and take an oral arthropodicidal agent, mak- Prevention (CDC) has reported both morbid- ing the blood meal toxic to the parasite and ity and mortality from chemical pesticides decimating the population. Although there used in bed bug extermination efforts.20,21 are no literature reports of its application to Physical methods have also been applied. bed bugs, the technique, using ivermectin, z Thermal treatment (heating or steam- has been successfully applied to other ecto- ing to >48ºC [120ºF] for one hour or freezing parasites, including scabies,24,25 lice,25,26 and to -20ºC [-4ºF] for one hour) has proven effec- the medically important arthropod vectors tive.22 Books, clothing, and other small items Triatoma27 and Anopheles.28 The TABLE shows may be placed in an oven or freezer (as long dosing recommendations for 3 of these as specified temperatures are met); steam- indications. ers are useful for treating furniture and base- In vitro studies demonstrate that Cimex boards. If an oven is used, diligent attention is susceptible to this same class of agents,29 must be paid to avoid too high a temperature, so there is reason for optimism. Future stud- which could create a fire hazard. Let patients ies will reveal the viability of this approach. know that, even at 120°F, some book bindings Another potential approach to bed bug con- and slipcovers could be damaged. trol is targeting the Wolbachia endosymbi-

386 The Journal of Family Practice | July 2012 | Vol 61, No 7 Bed bugs

onts. Elimination of these bacteria has been bor bed bugs. Fumigating used furniture associated with a significant decrease in was once common; it is still a good idea be- parasite reproduction9; this strategy has also fore second-hand items are brought into the been efficacious in treating human filarial house. Cardboard boxes in which used items .30 are commonly stored or transported can shelter bed bugs, too.33 z Deprive bed bugs of hiding places. Preventing infestation Decluttering one’s sleeping quarters decreas- Bed bugs depend largely on humans for their es the number of places bed bugs can hide. dissemination. They take refuge in or near This tactic diminishes the likelihood of an in- their host’s bed during the day, and when the festation becoming firmly established before bed or other object in which they are hiding being discovered. Intervention early in the is moved, they are transplanted to a new lo- course of infestation, when it is limited to a cation. They also migrate directly to adjacent single room, increases the likelihood of suc- apartments, hotel rooms, etc, along plumb- cessful elimination.33 ing and wiring or through cracks.16 Bed bugs and box-spring encasements are effective at hiding, and can survive for up can prevent bed bug infestations by blocking to a year without feeding.31 This contributes movement of the bugs into and out of their to the frequent failure of elimination efforts shelters. If encasements are placed during and the presence of bed bugs in hotels, fur- an infestation, it is important to keep them Tell patients nished apartments, theaters, shopping cen- in place for an extended period, given that that when they ters, airplanes, newly purchased houses, and bed bugs can survive for up to a year without stay at hotels, other places. feeding. Also effective is caulking and sealing it’s advisable Avoiding bites while in an infested facil- molding, joints, and cracks wider than the to keep their ity is difficult, if not impossible. But people thickness of a credit card in the room and in luggage in the can take steps to decrease the likelihood of furniture.33 bathroom. Bed bringing them home. Although there are no Vacuuming is part of the CDC’s recom- bugs typically strong evidence-based guidelines on pre- mendation for household pest control. But shelter within a venting infestation, pest control experts make vacuum cleaners can also transfer bed bugs few feet of their a number of recommendations,32 which you from infested to uninfested rooms. During host’s sleeping can pass on to your patients. an infestation, it’s important to empty vacu- place. z Protect luggage when traveling. um bags immediately. And sharing vacuum When staying in hotels, for instance, patients cleaners between dwellings is best avoided. should keep suitcases tightly closed when not in use. Protection is further enhanced A need for better solutions by placing suitcases in a sealed plastic bag; Although bed bugs are not competent as “contractor” trash bags available at hard- vectors for the transmission of infectious ware stores are large and durable. Keeping diseases, they are responsible for significant suitcases in the bathroom rather than the dermatitis, allergic reactions, and psycholog- sleeping quarters also decreases the pos- ical distress. Treatment of symptoms is effec- sibility of stowaways, as bed bugs typically tive in the short-term, but current methods shelter within a few feet of their host’s - of eliminating infestation are cumbersome, ing place. toxic, and are seldom completely successful. Immediate laundering of clothes upon New strategies are desperately needed. The returning home from a trip, and storing suit- CDC Web page (http://www.cdc.gov/nceh/ cases outside the living quarters can decrease ehs/topics/bedbugs.htm) is regularly up- risk, too.33 There are commercially available dated, and is a good source of information as suitcase heaters that raise the temperature of new approaches are developed. JFP the suitcase and its contents to insecticidal levels, but they are fairly cost-prohibitive. Correspondence z Mark K. Huntington, MD, PhD, Center for Family Medicine, Screen items brought into the home. 1115 East Twentieth Street, Sioux Falls, SD 57105; Used items, especially furniture, may har- [email protected] Continued

jfponline.com Vol 61, No 7 | July 2012 | The Journal of Family Practice 387 References 1. Usinger RI. Monograph of the (- pests of poultry. Annu Rev Entomol. 1990;35:101-126. Heteroptera). Vol VII. College Park, Md: Entomological Soci- 19. Moore DJ, Miller DM. Field evaluations of treat- ety of America; 1966. ment regimens for control of the common bed bug, Cimex 2. Berg R. Bed bugs: the dilemma. J Environ Health. lectularius (L.). Pest Manag Sci. 2009;65:332-338. 2010;72:32-35. 20. CDC. Acute illnesses associated with used to 3. Snetsinger R. Bed bugs & other bugs. In: Hedges S, ed. Mallis’ control bed bugs—seven states, 2003–2010. MMWR Morb Handbook of Pest Control. 8th ed. Cleveland, Ohio: GIE Me- Mortal Wkly Rep. 2011;60:1269-1274. dia; 1997:392-424. 21. Tawatsin A, Thavara U, Chompoosri J, et al. Insecticide re- 4. Eddy C, Jones SC. Bed bugs, public health, and social justice: sistance in bedbugs in Thailand and laboratory evaluation part 1, a call to action. J Environ Health. 2011;73:8-14. of insecticides for the control of and Ci- 5. Hurst S, Humphreys M. Bedbugs: not back by popular de- mex lectularius (Hemiptera: Cimicidae). J Med Entomol. mand. Dimens Crit Care Nurs. 2011;30:94-96. 2011;48:1023-1030. 6. Anderson A. The decade of bedbugs and fear. Environ Health 22. Benoit JB, Lopez-Martinez G, Teets NM, et al. Responses of Insights. 2011;5:53-54. the bed bug, , to temperature extremes 7. America’s 10 most infested cities. The Daily Beast; August and dehydration: levels of tolerance, rapid cold hardening 24, 2010. Available at: http://www.thedailybeast.com/ and expression of heat shock proteins. Med Vet Entomol. articles/2010/08/24/bedbug-outbreak-which-cities-are- 2009;23:418-425. most-infested.html. Accessed August 28, 2011. 23. Benoit JB, Phillips SA, Croxall TJ, et al. Addition of alarm 8. Hosokawa T, Koga R, Kikuchi Y, et al. Wolbachia as a bacterio- pheromone components improves the effectiveness of cyte-associated nutritional mutualist. Proc Natl Acad Sci U S desiccant dusts against Cimex lectularius. J Med Entomol. A. 2010;107:769-774. 2009;46:572-579. 9. Sakamoto JM, Rasgon JL. Geographic distribution of Wolba- 24. Heukelbach J, Feldmeier H. Scabies. Lancet. 2006;367: chia infections in Cimex lectularius (Heteroptera: Cimicidae). 1767-1774. J Med Entomol. 2006;43:696-700. 25. Fox LM. Ivermectin: uses and impact 20 years on. Curr Opin 10. Abou Gamra EM, el Shayed FA, Morsy TA, et al. The relation Infect Dis. 2006;19:588-593. between Cimex lectularius antigen and bronchial asthma in 26. Foucault C, Ranque S, Badiaga S, et al. Oral ivermectin in the Egypt. J Egypt Soc Parasitol. 1991;21:735-746. treatment of body lice. J Infect Dis. 2006;193:474-476. Covering 11. Delaunay P, Blanc V, Del Giudice P, et al. Bedbugs and infec- 27. Dias JC, Schofield CJ, Machado EM, et al. Ticks, ivermectin, mattresses and tious diseases. Clin Infect Dis. 2011;52:200-210. and experimental Chagas disease. Mem Inst Oswaldo Cruz. 12. Pritchard MJ, Hwang SW. Cases: severe anemia from bed- 2005;100:829-832. box-springs at bugs. CMAJ. 2009;181:287-288. 28. Kobylinski KC, Sylla M, Chapman PL, et al. Ivermectin mass home with 13. Delaunay P. Cimex lectularius or bed bug: vector of infec- drug administration to humans disrupts malaria parasite tious agents and pathogenic role. Available at: http://www. transmission in Senegalese villages. Am J Trop Med Hyg. encasements clinicaltrials.gov. Identifier: NCT01089465. Accessed Novem- 2011;85:3-5. ber 29, 2011. 29. Ostlind DA, Cifelli S, Conroy JA, et al. A novel Cimex lectularius– can prevent 14. Rieder E, Hamalian G, Ying P. Psychiatric implications of bed- assay for the detection of systemic ectoparasiticide infestations bugs. Presented at: 164th Annual Meeting of the American activity. Southwest Entomol. 2001;26:181-186. Psychiatric Association; May 14-18, 2011; Honolulu, Hawaii. 30. Tamarozzi F, Halliday A, Gentil K, et al. Onchocerciasis: the by blocking Abstract NR01-51. role of Wolbachia bacterial endosymbionts in parasite biol- movement 15. Roos TC, Alam M, Roos S, et al. Pharmacotherapy of ecto- ogy, disease pathogenesis, and treatment. Clin Microbiol Rev. parasitic infections. Drugs. 2001;61:1067-1088. 2011;24:459-468. of bugs in and 16. Goddard J, deShazo R. Bed bugs (Cimex lectularius) and clini- 31. Kells SA, Hahn J. Prevention and control of bed bugs in resi- out of shelters. cal consequences of their bites. JAMA. 2009;301:1358-1366. dences. Available at: http://www.extension.umn.edu/distri- 17. Centers for Disease Control and Prevention and Environmen- bution/housingandclothing/dk1022.html. Accessed Novem- tal Protection Agency. Joint statement on bed bug control in ber 29, 2011. the United States from the U.S. Centers for Disease Control 32. Got bedbugs? Your hotel might! Available at: http://www. and Prevention (CDC) and the U.S. Environmental Protection smartertravel.com/travel-advice/avoiding-bedbugs-every- Agency (EPA). Atlanta, Ga: US Department of Health and Hu- traveler-nightmare.html?id=4726511. Published April 25, man Services; 2010. Available at: http://www.cdc.gov/nceh/ 2010. Accessed November 29, 2011. ehs/Publications/Bed_Bugs_CDC-EPA_Statement.htm. Ac- 33. US Environmental Protection Agency. Bed bug information. cessed June 15, 2012. Available at: http://www.epa.gov/bedbugs/index.html. Ac- 18. Axtell RC, Arends JJ. Ecology and management of arthropod cessed November 29, 2011. Osteoarthritis as a Chronic Disease: Maximizing Management in Primary Care

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