How can lice be seen on a comb? - briefly
Run a fine-toothed comb through wet hair, then examine the comb teeth under bright light to detect the insects and their attached eggs. Lice appear as 2–3 mm brownish bodies, while nits are tiny, oval, and firmly glued to the hair shaft.
How can lice be seen on a comb? - in detail
Detecting head‑lice with a fine‑toothed comb requires a systematic approach. The comb separates hair strands, trapping adult insects and their eggs, which become visible against a contrasting surface.
A suitable comb features teeth spaced 0.2–0.3 mm apart. Plastic or metal variants work equally well; the key is rigidity to prevent hair from slipping. Before use, wet the hair with a conditioner or water. Moisture immobilizes the parasites and reduces static, allowing the teeth to glide smoothly.
Procedure
- Place a white towel or sheet on a flat surface; the light background highlights translucent eggs and dark bodies.
- Position a bright lamp or natural daylight directly over the combed area to eliminate shadows.
- Starting at the scalp, pull the comb through a small section of hair, moving from root to tip in a single stroke.
- After each pass, inspect the teeth with a magnifying lens (10–20×) or a smartphone camera set to macro mode.
- Transfer any captured organisms to a disposable container for further examination or disposal.
- Repeat the process across the entire head, focusing on the nape, behind the ears, and near the crown where lice congregate.
What to observe
- Adult lice: brownish‑gray bodies, 2–4 mm long, with six legs. The head and thorax appear broader than the abdomen; legs are clearly visible under magnification.
- Nits (eggs): oval, 0.8 mm long, firmly attached to the hair shaft at a 30–45° angle. Viable eggs are tan‑brown; empty shells are translucent and may crumble when gently nudged.
- Fecal specks: tiny dark particles near the base of the hair, indicating feeding activity.
Tips for optimal visibility
- Use a handheld magnifier or a digital zoom to differentiate live lice from debris.
- Conduct the examination in a well‑ventilated room to avoid condensation on the comb, which can blur the view.
- After each combing session, rinse the comb in hot, soapy water to remove residual organisms and prevent reinfestation.
Following these steps yields a reliable visual confirmation of infestation and guides appropriate treatment measures.