How do bedbugs locate people? - briefly
Bedbugs sense a host through body heat, carbon‑dioxide emissions, and vibration cues. They move short distances toward the source of these signals to reach a sleeping surface.
How do bedbugs locate people? - in detail
Bedbugs (Cimex lectularius) rely on a combination of sensory inputs to identify a suitable host. The primary drivers are airborne chemical signals, thermal gradients, and mechanical disturbances generated by a sleeping human.
Airborne cues include:
- Elevated carbon‑dioxide levels emitted by respiration, which create a concentration plume that bedbugs follow up‑gradient.
- Body heat that produces a measurable temperature rise; thermoreceptors in the insect’s antennae detect gradients as small as 0.1 °C.
- Volatile organic compounds (VOCs) from skin secretions, sweat, and breath; specific kairomones such as lactic acid, ammonia, and fatty acids attract the insects.
- Pheromonal traces left by conspecifics that signal the presence of a recent blood meal and enhance host‑seeking efficiency.
Mechanical cues complement chemical detection:
- Subtle vibrations caused by breathing, cardiac activity, and movement transmit through the mattress and bedding; mechanoreceptors in the legs and antennae register these signals.
- Direct tactile contact with fabric fibers or skin initiates a rapid probing response, prompting the insect to commence feeding.
Integration of these modalities occurs in the central nervous system, where signal weighting adjusts according to environmental conditions. In darkness, thermal and CO₂ cues dominate; in confined spaces with limited airflow, vibrational information becomes more salient. The resulting behavior is a directed locomotion toward the host, followed by a probing phase that culminates in blood ingestion.