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Bug Bites and Stings
Skin: Bed Bugs
MAJ Daniel Schissel, MC, USAIntroduction: The bed bug (Cimex lectularius) is a 3-5 mm, wingless, 6 legged, reddish brown, flattened,
oval bodied, blood-sucking insect. It hides in crevices, bedding, or furniture, and normally emerges to feed
at night in the dark. It is capable of traveling long distances in search of its blood meal, often from one
house to another. Under normal conditions, it feeds about once a week but has been known to survive
6 months to a year without feeding. It characteristically leaves 3 bite marks in succession on its victim:
“breakfast, lunch and dinner.”
Subjective: Symptoms
Bite is not felt while sleeping; small asymptomatic macule at bite site; if sensitized (having developed an
allergic reaction to the salivary secretions) have intensely pruritic papules that may evolve into a nodule that
persists for weeks.
Objective: Signs
Using Basic Tools: Lesion is variable from a small, erythematous macule in non-sensitized individuals
to an intensely pruritic papule or wheal, often with a central hemorrhagic dimple, in sensitized individuals.
Characteristically 2-3 lesions grouped in a linear fashion on the exposed areas of the face, neck, arms, or
hands. Bullae are more common in younger patients. Secondary infection of the excoriated lesions often
clouds the clinical presentation.
Assessment:
Diagnosis based on clinical morphologic criteria and history of exposure.
Differential Diagnosis - other arthropod assault, nummular dermatitis, irritant or allergic dermatitis (see
appropriate sections).
Plan:
Treatment
Relieve pruritus with antihistamines (e.g., Benadryl) and prevent secondary infection (topical antibiotic lotion,
e.g., Neosporin). Use topical steroid cream (1% hydrocortisone) on more advanced cases.
Patient Education
General: Eliminate the bug from the environment with insecticides (consult preventive medicine).
Follow-up Actions
Evacuation/Consultation Criteria: Evacuation is not necessary. Consult as above.
Skin: Centipede Bites
COL Roland J. Weisser, Jr., MC, USAIntroduction: Centipedes are elongated, cylindrical arthropods having a single pair of legs ending in claws
on each body segment (millipedes have two leg pairs per segment). Centipedes have been reported up to 26
cm long, and are frequently more colorful (red, yellow, black, and blue) than millipedes and thus more likely
to be sought as trophies. They are widely distributed, especially in warm, temperate and tropical regions.
Centipedes live in moist environments, most commonly in forests amongst leaf litter or rotting timber, in
caves, along the seashore (under damp seaweed and other detritus). Most have very poor or non-existent
vision. Unlike millipedes, centipedes are carnivorous. The legs on the first body segment are modified into
fangs that bite and channel venom into prey. In addition to the venom, some species exude defensive