In 2004, knowing of my medical interest in arthropods, a resident came to my office to discuss an “unusual case” of pubic louse infestation seen at another hospital: a middle-aged woman had been afflicted for months with a skin eruption with excoriation and impetigo that involved the arms and legs but not the pubic area.
See related article, page 207
In a bag, the resident had a dead insect, 5 mm in length, with a brown, lens-shaped body and short hairs on the pronotum that were visible with a hand lens. An attending dermatologist at the other hospital had identified the insect—incorrectly —as a pubic louse.
With deference, I informed the resident that I did not share the opinion that this was a pubic louse, unless the insect represented a new “Cleveland variant” of the species (a reference to the 1975 Bruce Maness sci-fi film, The Tomato That Ate Cleveland). Rather, I stated, “I believe this is a bedbug, but I have not seen many specimens.”
In hindsight, these words were prophetic, for since 2004, the incidence of bedbug infestations has remarkably surged.1 The trend has not abated, making the review by Ibrahim et al in this issue of the Cleveland Clinic Journal of Medicine timely for all practitioners.2
BEDBUGS ARE BACK…
Bedbugs have plagued man for millennia. In 1939, it was estimated that 4 million Londoners (in a city of 8.5 million) were bitten by bedbugs each night.3 However, as Ibrahim et al describe, long-acting pesticides introduced during World War II dramatically reduced infestation rates. By 1997, some college entomology programs reported difficulty in locating a single teaching specimen.4
The modern resurgence of bedbugs is multifactorial, including a ban on long-acting pesticides such as dichlorodiphenyltrichloro-ethane (DDT), as well as population growth and increased travel. In days past, bedbug infestations may have pertained to hygiene and social status. But today, travel is a major factor in the resurgence, and bedbugs now affect a broader segment of the population, including the affluent—something that must be kept in mind in the clinical setting.5
…AND THEY’RE EVERYWHERE
Many prominent US cities are experiencing near-epidemic numbers of bedbug infestations (Table 1). Bedbug infestations occur not only in homes and hotel rooms, but also in hospitals,6 office buildings,7 movie theaters,8 schools,9 and even on subways and trains,10 expanding the number of people potentially exposed.
2016 Top 10 US cities for bedbug infestation
Understanding that bedbugs affect more than people who are in bed, or with hygiene challenges, Ibrahim et al describe the presentation of bedbug bites—useful information for all practitioners, regardless of medical specialty.
Bedbugs bite skin that is exposed during sleep (ie, the distal extremities and the head, face, and neck). Quasilinear bites, in groups of three (the notorious “breakfast, lunch, and dinner” sign) are a good clue to remember. Unusually exuberant reactions to bedbug bites may be confused with autoimmune bullous conditions or primary vasculitides.11
NOT ALL WHO ARE BITTEN HAVE REACTIONS
Intricate entomologic studies have shown that substances in bedbug saliva drive bite reactions.12,13 However, as Ibrahim et al mention, not all bites provoke a reaction in all persons.
This fact cannot be overstated, for providers in primary care and urgent and emergency care settings may have learned to ask questions about scabies such as, “Are other persons in the household similarly affected?” While it is uncommon for a person with scabies not to present with visible skin lesions, one does not want to misinterpret this historical detail in the setting of bedbug bites. If one person in a household has lesions and another does not, this does not exclude a bedbug infestation!
Ibrahim et al emphasize that treatment of bedbug bites is supportive in nature. Most often, extermination in the home or any other setting should be conducted by professionals. During travel, prevention by inspection is widely advocated.5 There has been interest in using oral ivermectin in affected patients to adversely affect the bedbug colony, but to date, early experiments have encountered daunting pharmacokinetic concerns.14
PSYCHOLOGICAL AND OTHER SEQUELAE
A final consideration in bedbug infestations is any lasting sequelae beyond the bites themselves. Bedbug infestations severe enough to cause anemia and exacerbate or trigger adverse cardiac events have been reported.15 While bedbugs carry human pathogens such as methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus faecium, hepatitis B virus, Bartonella quintana, and Trypanosoma cruzi, Ibrahim et al correctly inform the reader that there are no compelling reports of transmission of these diseases via bedbug bites.16
However, there may be lasting psychological sequelae. Anxiety, hypervigilance, insomnia, avoidance behaviors, and personal dysfunction can persist, even long after the infestation has been eradicated.
Bedbugs are a national and even global health problem worthy of familiarity by all healthcare providers, regardless of specialty. In this regard, Ibrahim et al succinctly and accurately provide a functional and clinically useful guide.
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