How does a subcutaneous tick bite a person? - briefly
A tick inserts its mouthparts through the skin, anchoring with a barbed hypostome while secreting saliva that contains anticoagulants and anesthetics. This creates a painless, subdermal attachment that can last for several days as the tick feeds.
How does a subcutaneous tick bite a person? - in detail
A subcutaneous tick attaches by inserting its mouthparts through the skin’s outer layers and anchoring itself in the dermal tissue. The process begins when the tick detects a host through heat, carbon‑dioxide, and movement. Once contact is made, the tick climbs onto the skin and positions its hypostome—a barbed feeding apparatus—perpendicular to the surface.
The hypostome penetrates the epidermis and reaches the dermis, where collagen fibers provide a stable matrix. As the tick’s muscles contract, the barbs embed deeper, preventing easy removal. Simultaneously, the tick secretes a complex saliva containing anticoagulants, immunomodulators, and analgesic compounds. These substances:
- Inhibit blood clotting, ensuring a continuous flow.
- Suppress the host’s immune response, reducing inflammation.
- Numb the bite area, limiting the host’s awareness of the attachment.
After securing the feeding site, the tick inserts a flexible tube called the salivarium, which transports saliva to the bite wound. Blood is then drawn through a second tube, the pharyngeal canal, into the tick’s foregut. The tick expands its body size gradually as it ingests blood, often over several days.
Throughout feeding, the tick’s cement proteins harden around the hypostome, creating a robust seal within the dermal tissue. This cement layer further stabilizes the attachment and protects the feeding site from host defenses. When the tick detaches, the cement may remain embedded, sometimes causing a lingering puncture wound that can serve as an entry point for pathogens.
In summary, the bite involves:
- Detection and mounting on the host.
- Hypostome penetration into the dermis.
- Barbed anchoring and cement secretion.
- Saliva injection with anticoagulant and immunosuppressive agents.
- Continuous blood uptake via the pharyngeal canal.
- Gradual enlargement of the tick’s body until engorgement, followed by detachment.