Why do bedbugs bite humans? - briefly
Bedbugs bite humans to obtain a «blood meal» required for reproduction and development. They locate hosts by sensing body heat, carbon‑dioxide emissions, and specific chemical cues.
Why do bedbugs bite humans? - in detail
Bedbugs are obligate hematophagous insects that obtain nourishment exclusively from the blood of warm‑blooded hosts. The primary driver of feeding is the requirement for protein, lipids, and iron to support development and reproduction; each female must ingest several blood meals before laying a viable clutch of eggs.
Feeding is initiated by a suite of sensory cues. Bedbugs locate a host through:
- Detection of elevated temperature emitted by the body.
- Sensing of carbon dioxide exhaled during respiration.
- Recognition of skin‑derived chemicals such as lactic acid and fatty acids.
These cues trigger a rapid movement toward the exposed skin, typically during the night when the host is at rest.
The feeding apparatus consists of a slender, needle‑like proboscis that penetrates the epidermis. Saliva injected during the bite contains anticoagulant proteins that prevent clotting, as well as anesthetic compounds that reduce the host’s perception of the puncture. The insect extracts blood for 5–10 minutes before disengaging, leaving a faint, often unnoticed mark.
Environmental conditions influence feeding frequency. Ambient temperatures between 24 °C and 30 °C accelerate metabolism, increasing the number of meals required per day. High population density and limited hiding places heighten competition, prompting more aggressive host seeking.
Repeated bites may provoke cutaneous reactions ranging from mild erythema to intense pruritus. Scratching can introduce bacterial pathogens, leading to secondary skin infections. Although bedbugs are not known to transmit disease agents, the psychological impact of infestation can be significant.
Understanding the physiological and behavioral mechanisms behind blood feeding informs control strategies, emphasizing early detection, environmental management, and targeted insecticide application.