How can you identify lice in hair? - briefly
Examine the scalp and hair for live, gray‑brown insects roughly the size of a sesame seed and for oval, white nits glued within ¼ inch of the scalp. Persistent itching or a tickling sensation typically confirms an infestation.
How can you identify lice in hair? - in detail
Lice detection begins with a thorough visual inspection of the scalp and hair shafts. Use a fine-toothed metal comb, preferably a lice comb with teeth spaced 0.2 mm apart, on dry or slightly damp hair. Run the comb from the scalp to the ends in small sections, wiping each pass on a white tissue or towel to reveal any organisms.
Key indicators include:
- Live insects: Adult head lice are about 2–3 mm long, grayish‑white, and move quickly when disturbed. They cling to hair shafts close to the scalp.
- Nits: Oval, oval‑shaped eggs measuring 0.8 mm, attached firmly to the hair shaft at a 45° angle. Viable nits appear white or yellowish; empty shells (nits that have hatched) are translucent and may crumble when pressed.
- Egg shells: Look for a “capped” appearance where the shell’s operculum is still intact, indicating an unhatched egg.
- Scalp irritation: Redness, scratching marks, or small sores may accompany infestation, though they are not definitive without visual confirmation.
During inspection, focus on typical habitats:
- Hairline and behind ears – areas with warm, moist conditions.
- Neck and nape – where hair is dense and close to the skin.
- Parting lines – especially in school‑age children, where hair is frequently combed.
If a comb pass yields several live lice or multiple firmly attached nits per 1‑cm segment of hair, an infestation is present. Isolated, loose nits without the characteristic 45° angle may be remnants from a previous infestation.
Confirmatory steps:
- Microscopic examination (optional): Place collected specimens on a slide, cover with a coverslip, and examine at 40× magnification to differentiate live lice from shed exoskeletons.
- Repeat inspection after 24–48 hours: New nits become visible as eggs hatch, reinforcing the diagnosis.
Accurate identification relies on systematic combing, recognition of the lice’s morphology, and assessment of attachment patterns rather than solely on subjective symptoms.