How to determine if a person has lice? - briefly
Examine the scalp and hair for active lice and attached eggs, focusing on the nape, behind the ears, and under the hairline; use a fine-toothed comb on damp hair to reveal any specimens. Confirm suspicion by noting persistent itching, redness, or the presence of brownish, oval nits adhered firmly to hair shafts.
How to determine if a person has lice? - in detail
Detecting a head‑lice infestation requires systematic visual examination and awareness of characteristic symptoms. The adult parasite measures 2–4 mm, moves quickly, and lays eggs (nits) firmly attached to hair shafts near the scalp.
First, observe the scalp for itching that intensifies after heat exposure or stress; the itch results from an allergic reaction to saliva. Second, look for small, grayish or white specks adhered to hair strands within ¼ inch of the scalp. These specks are nits; they differ from dandruff by their fixed position and oval shape. Third, use a fine‑toothed louse comb on wet, conditioned hair. Run the comb from the roots to the tips, wiping the teeth after each pass. Any live insects captured on the comb indicate infestation.
Key visual cues include:
- Live lice: brownish, mobile insects, often visible on the neck, behind ears, or at the hairline.
- Nits: translucent, oval, attached at an angle to the shaft; older nits appear darkened.
- Secondary signs: scalp redness, small sores from scratching, or a “tickling” sensation when hair is brushed.
If uncertainty remains after combing, collect a few hairs with attached nits and examine them under a magnifying lens (10×) or a light microscope. Confirmed presence of viable lice or viable eggs warrants treatment.
Regular checks—once a week for two weeks after treatment and monthly during an outbreak—prevent re‑infestation. Proper hygiene, avoiding sharing combs, hats, or pillowcases, and laundering personal items in hot water (≥ 130 °F) complement detection efforts.