How can fleas bite? - briefly
«Fleas bite by employing needle‑like mouthparts that pierce the skin and inject saliva containing anticoagulants, causing immediate irritation». The resulting puncture appears as a tiny, red, itchy spot.
How can fleas bite? - in detail
Fleas obtain blood through a specialized mouthpart that functions as a piercing‑sucking organ. The head houses a short, hardened proboscis composed of two slender stylets that slide apart to create a channel for fluid intake. One stylet pierces the host’s epidermis, while the other delivers saliva containing anticoagulant compounds that prevent clotting.
The feeding sequence proceeds as follows:
- Detection of host heat, carbon‑dioxide, and movement.
- Rapid insertion of the stylets into the skin surface.
- Injection of salivary enzymes that inhibit platelet aggregation and dilate blood vessels.
- Creation of a capillary‑sized tunnel through which blood is drawn upward by capillary action.
- Withdrawal of the proboscis after a blood meal lasting several minutes.
Saliva components, such as anticoagulants and anesthetics, facilitate uninterrupted feeding and reduce host awareness of the bite. The mechanical action of the stylets produces a minute puncture, often invisible to the naked eye, while the accompanying inflammatory response generates a small, itchy papule at the site.
Repeated feeding can lead to skin irritation, secondary bacterial infection, and transmission of pathogens such as Yersinia pestis or Rickettsia species. Effective control measures target adult fleas, larvae, and eggs to interrupt the feeding cycle and prevent associated health risks.