Bedbugs

Bedbugs, including Cimex lectularius, the common bedbug, and C. hemipterus, the tropical bedbug, are flat, brown insects that bite humans to obtain a blood meal. A global resurgence of bedbugs has been observed in the past 30 years. One reason for this resurgence is increasing resistance to insecticides.

Bedbugs thrive in warm, dark environments. They are most commonly found in high-occupancy places such as hotels, motels, hostels, and shelters. They often live in mattresses, furniture, flooring, and walls. Bedbugs are active at night are attracted to humans by their body temperature and exhaled carbon dioxide. 

Bed bug bites cause multiple, itchy, red bumps on exposed areas of the body such as the head, neck, arms, and legs. The bumps can have a dark red mark in the center and may be arranged in a group or a line. Some bites can cause blisters. Skin lesions may be noticeable immediately upon wakening but sometimes develop over the following days. Scratching of pruritic lesions may lead to secondary infections such as impetigo, ecthyma, folliculitis, or cellulitis.

Patients typically present with cutaneous lesions that appear to be bites. However, associating these lesions with bedbug bites may be difficult because people may not know their house has become infested. The presence of exoskeletons or bedbug dark fecal spots on the mattress and bedding is a clear sign of infestation.

Bedbugs have been shown to carry more than 45 infectious agents, and some experimental data have suggested they might transmit disease vectors such as Trypanosoma cruzi, that causes Chaga’s disease, Bartonella quintana, that causes louse-borne trench fever, and Borrelia recurrentis, that causes recurrent fever. There are currently no known cases of transmission of any infectious agents by bedbugs to humans.

References

Parola P and Izri A. Bedbugs, June 4, 2020, N Engl J Med 2020; 382:2230-2237.

Voelker R. What are Bedbugs? JAMA 2025;333:732.