What does a louse look like on a person, what are its signs, and how is it treated? - briefly
A louse is a small, wingless, flattened insect about 2–4 mm long, gray‑brown in color, that attaches to hair shafts and produces itching along with visible nits glued near the scalp. Treatment involves applying a pediculicide shampoo or lotion as directed, then combing out live lice and nits and laundering personal items.
What does a louse look like on a person, what are its signs, and how is it treated? - in detail
A head louse is a tiny, wing‑less insect measuring 2–4 mm in length. Its body is flattened, with a broad head that bears six short bristles (chaetae) and a pair of clawed legs adapted for gripping hair shafts. The abdomen is segmented and covered with fine, translucent scales that give the insect a grey‑brown hue. Adult females appear slightly larger and more robust than males, while nymphs resemble miniature adults but lack fully developed reproductive organs.
Typical indicators of infestation include:
- Small, live insects moving quickly through the hair, especially near the scalp.
- Nits (lice eggs) attached firmly to the side of hair shafts, within 1 cm of the scalp; they appear as oval, white or yellowish bodies and cannot be easily brushed off.
- Itching or a crawling sensation on the scalp, caused by the louse’s saliva.
- Red, inflamed patches on the scalp or neck, sometimes accompanied by secondary bacterial infection from scratching.
Effective management involves both chemical and mechanical strategies:
- Pediculicidal agents – apply a recommended concentration of permethrin 1 % or pyrethrin‑based shampoo, leave for the specified contact time, then rinse thoroughly. For resistant cases, use a 0.5 % malathion lotion or a dimethicone‑based product, following the manufacturer’s instructions.
- Nit removal – comb the hair with a fine‑toothed nit comb on wet, conditioned hair after treatment; repeat every 2–3 days for at least two weeks to eliminate newly hatched nymphs.
- Environmental control – wash bedding, hats, and hair accessories in hot water (≥ 60 °C) and dry on high heat; seal non‑washable items in a sealed plastic bag for two weeks.
- Follow‑up inspection – examine the scalp and hair 7–10 days after initial treatment; retreat if live lice are still present.
Prompt, thorough application of these measures eradicates the parasite and prevents re‑infestation.