How does a tick nymph bite? - briefly
A tick nymph penetrates the host’s skin with its hypostome, injects saliva that prevents clotting, and stays attached for several days while ingesting blood.
How does a tick nymph bite? - in detail
A tick nymph locates a host by detecting carbon dioxide, heat, and movement. Upon contact, the nymph climbs onto the skin and searches for a suitable attachment site, typically an area with thin skin and abundant blood vessels.
The feeding apparatus consists of a pair of chelicerae that cut the epidermis and a hypostome, a barbed structure that anchors the nymph in the dermis. The hypostome’s backward‑facing teeth prevent easy removal. Salivary glands release a cocktail of substances that:
- Dilate blood vessels, increasing blood flow.
- Inhibit clotting by disrupting fibrin formation.
- Suppress local immune responses, reducing inflammation.
These secretions allow the nymph to ingest blood continuously for several days. The feeding cycle proceeds as follows:
- Attachment – chelicerae pierce the skin; hypostome embeds.
- Saliva injection – anti‑hemostatic and immunomodulatory compounds enter the bite site.
- Engorgement – blood is drawn through the foregut into the midgut, where it is stored and digested.
- Detachment – after reaching repletion, the nymph releases its grip and drops off the host.
During engorgement, the nymph can acquire or transmit pathogens. Transmission risk rises after the tick has been attached for 24–48 hours, as pathogens migrate from the salivary glands to the bite wound.
The entire process is microscopic, painless, and often unnoticed because the saliva contains anesthetic agents that block sensory nerves. Consequently, a nymph may remain attached for the full feeding period without alerting the host.