How does an encephalitis tick look under the skin in a human? - briefly
When attached, the tick presents as a small, dark, raised nodule about 2–5 mm across, often showing a central punctum where it inserts its mouthparts. As it feeds, the body expands and may become reddish‑brown, giving the spot the appearance of a tiny bump beneath the skin.
How does an encephalitis tick look under the skin in a human? - in detail
The tick that can transmit encephalitis attaches by inserting its hypostome into the dermis. Initially it appears as a small, flat, gray‑brown organism about 2–3 mm in length. Its dorsal shield (scutum) is smooth and bears faint, irregular patterns that may be difficult to see without magnification. The legs are clearly visible, extending outward in a forward‑facing stance; each leg ends in tiny claws that grip the skin.
Within a few hours the tick begins to feed, and its abdomen swells. Engorgement produces a rounded, balloon‑like shape, increasing the overall size to 5–10 mm or more. The body surface becomes a lighter, pinkish hue as blood fills the midgut. The mouthparts remain embedded, with the palps and hypostome forming a dark, needle‑like projection that may be seen as a tiny black point at the center of the attachment site.
Visible signs on the skin include:
- A localized, raised bump matching the tick’s outline.
- A central dark puncture corresponding to the feeding apparatus.
- Possible erythema or slight redness surrounding the area, often subtle.
- No immediate ulceration; the skin remains intact over the attachment point.
If the tick is removed prematurely, the mouthparts may remain partially embedded, appearing as a small, black filament protruding from the skin. Complete removal of the organism, including the hypostome, eliminates the visible structure but may leave a faint scar or discoloration that fades over weeks.
Microscopic examination reveals the tick’s dorsal plates, the arrangement of its eight legs, and the engorged abdomen filled with blood, confirming its identity and feeding status.