What does a tick look like under a human's skin? - briefly
Under the epidermis a feeding tick appears as a small, dark, flattened or round spot, resembling a tiny black dot or a swollen, translucent sac. As it fills with blood, the body expands to a pale, balloon‑like shape that can be felt as a firm bump.
What does a tick look like under a human's skin? - in detail
A feeding tick attaches its head‑quarters, the capitulum, deep within the epidermal layers. The mandibles and hypostome pierce the skin, creating a narrow tunnel that is often invisible to the naked eye. The visible portion of the parasite remains on the surface, but the abdomen swells dramatically as it fills with blood.
The engorged body exhibits several distinct visual cues:
- Shape: a rounded, balloon‑like silhouette that can expand from a few millimeters to over a centimeter in diameter.
- Color: a transition from tan or reddish‑brown in the unfed state to dark gray, purple, or black when fully engorged.
- Surface texture: a smooth, glossy cuticle that may appear slightly translucent, allowing underlying blood to be seen as a faint reddish hue.
- Scutum: a hardened dorsal plate present on the anterior half of many species, remaining a lighter, matte patch amid the swollen abdomen.
- Legs: eight slender appendages that may be partially hidden beneath the expanded body, often giving the tick a flattened appearance against the skin.
Internally, the tick’s gut is filled with a liquid mixture of host blood and digestive enzymes. This content creates a visible bulge beneath the epidermis, sometimes mistaken for a cyst or allergic reaction. The feeding canal, measuring 0.1–0.2 mm in diameter, anchors the parasite and prevents the host’s immune cells from reaching the interior.
The surrounding skin often reacts with a small, erythematous halo. The halo’s margin is usually sharp, indicating the precise location of the mouthpart insertion. In some cases, a thin serous fluid may seep around the attachment site, forming a clear halo that outlines the tick’s position.
Overall, a tick in the feeding phase presents a rapidly enlarging, darkened, smooth‑shelled mass on the skin surface, with a concealed mouthpart tunnel that penetrates the epidermis and a surrounding reddened rim that marks the point of attachment.