What does a louse look like and how should it be eliminated?

What does a louse look like and how should it be eliminated? - briefly

A louse is a tiny, wing‑less parasite about 2–4 mm long, with a flattened, elongated body, six clawed legs, and a color ranging from gray to brown. Effective eradication combines thorough combing with a nit‑comb after applying an FDA‑approved pediculicide, followed by washing bedding and clothing in hot water.

What does a louse look like and how should it be eliminated? - in detail

Lice are small, wing‑less insects that feed on human blood. Adult head‑lice measure 2–4 mm in length, have a flattened, elongated body, six legs with clawed tarsi for gripping hair shafts, and a tan‑to‑gray coloration that may appear darker after a blood meal. Nymphs resemble adults but are half the size and lack fully developed reproductive organs. Eggs, known as nits, are oval, 0.8 mm long, and firmly attached to the base of each hair strand by a cement‑like secretion; they appear white or yellowish and are difficult to see against the scalp.

Elimination requires a combination of mechanical removal, chemical treatment, and environmental decontamination:

• Mechanical removal
  1. Wet comb the hair with a fine‑toothed lice comb every 2–3 days for two weeks.
  2. Examine each section under bright light; pull out visible insects and nits with tweezers.
• Topical pediculicides
  • Apply a 1% permethrin lotion or a 0.5% malathion solution according to package directions; leave on scalp for the recommended time, then rinse.
  • For resistant infestations, consider a prescription ivermectin lotion (0.5%) applied once, followed by a second application after 7 days.
• Oral therapy
  • Single‑dose oral ivermectin (200 µg/kg) may be prescribed for severe or recurrent cases; repeat after 7 days if needed.
• Environmental measures
  • Wash clothing, bedding, and towels used within the previous 48 hours in hot water (≥60 °C) and dry on high heat.
  • Seal non‑washable items in a sealed plastic bag for two weeks to starve any surviving lice.
  • Vacuum carpets, upholstery, and car seats; discard vacuum bags immediately.

Monitoring continues for four weeks post‑treatment; any newly detected insects indicate treatment failure and necessitate a repeat cycle. Prompt, thorough execution of these steps eradicates the infestation and prevents re‑colonization.