How does a tick crawl under the skin? - briefly
The parasite detects a vulnerable spot with its front legs, then inserts the barbed «hypostome» into the epidermis to anchor itself. Muscular contractions draw the body deeper into the dermal layer while saliva lubricates the passage.
How does a tick crawl under the skin? - in detail
Ticks attach to a host by detecting heat, carbon dioxide and movement. Once contact is made, the parasite inserts its fore‑legs to grasp the skin surface and then raises its body to position the capitulum, the specialized feeding apparatus, against the epidermis.
The capitulum consists of chelicerae and a hypostome. The chelicerae cut a shallow groove in the outer layer, while the hypostome, covered with microscopic barbs, pierces the epidermis and advances into the dermal tissue. Muscular contractions of the tick’s body drive the hypostome forward, allowing it to slide beneath the superficial layers without breaching deeper structures.
During penetration, the tick secretes a cocktail of enzymes and anticoagulants. Salivary proteins degrade keratin and collagen, soften the extracellular matrix, and prevent blood clotting. This chemical action reduces resistance and creates a lubricated channel for the hypostome to progress.
The process proceeds as follows:
- Detection of host cues and initial attachment.
- Grasping of skin with fore‑legs; elevation of the body.
- Deployment of chelicerae to create an entry point.
- Advancement of the barbed hypostome into the dermis, aided by muscular force.
- Release of salivary enzymes that dissolve tissue components and inhibit hemostasis.
- Stabilization of the feeding site through cement‑like secretions that harden around the hypostome, anchoring the tick securely.
The tick remains partially embedded, with only the dorsal shield visible, while the mouthparts stay concealed within the host’s skin. Continuous feeding is sustained by the anti‑inflammatory and immunomodulatory compounds in the saliva, which suppress local immune responses and facilitate prolonged blood intake.