How can you distinguish lice eggs? - briefly
Lice eggs (nits) are oval, 0.8 mm long, firmly glued to the hair shaft within 1 cm of the scalp, and appear white or yellowish, whereas hair dandruff flakes are larger, loosely attached, and lighter in color. The attachment point and proximity to the scalp are the most reliable visual cues.
How can you distinguish lice eggs? - in detail
Lice eggs, commonly called nits, possess distinct characteristics that set them apart from other scalp particles. They measure approximately 0.8 mm in length, are oval‑shaped, and have a smooth, translucent shell that becomes darker as the embryo develops. The shell adheres firmly to the hair shaft at an angle of 30–45°, typically within 1 cm of the scalp where the temperature supports incubation. This attachment is achieved by a cement‑like substance that resists easy removal; a gentle tug with a fine‑tooth comb will often cause the hair to break rather than the nit to detach.
Color progression provides a reliable cue. Freshly laid eggs appear white or pale yellow; after 2–3 days they turn a lighter brown, and by day 5 they become a darker amber. Fully matured nits are solid brown and may display a tiny dark spot at one end, indicating the developing nymph. In contrast, dandruff flakes are larger, irregularly shaped, and lack attachment to the hair; they can be brushed away easily and do not exhibit the same color shift.
Location on the hair also aids discrimination. Nits are most commonly found behind the ears, at the nape of the neck, and along the hairline—areas where the scalp is warm and hair is dense. Dandruff and product residue tend to accumulate on the forehead and scalp surface, not along the shaft.
Magnification enhances identification. A handheld magnifying lens (10×) or a dermatoscope reveals the characteristic oval outline, the clear cement line at the base, and the embryonic outline within. Under a microscope, the shell shows a smooth surface with no ridges, and the interior may reveal a developing organism.
To verify a suspected nit, follow these steps:
- Isolate a single hair strand with the suspected particle.
- Examine under magnification, noting size, shape, and attachment angle.
- Observe color; compare with the known developmental palette.
- Attempt gentle removal with a fine‑tooth comb; a true nit will resist detachment without breaking the hair.
These criteria enable precise differentiation of lice eggs from other scalp debris, ensuring accurate diagnosis and appropriate treatment.