What do lice look like and how can they be eliminated? - briefly
Lice are small, wing‑less insects 2–4 mm long, with a flattened, elongated body, six grasping legs, and a gray‑brown to reddish coloration; their eggs (nits) appear as tiny, oval, cement‑attached shells on hair shafts. Effective eradication combines a medicated shampoo or lotion containing permethrin or dimethicone, meticulous nit‑combing, and a repeat treatment after 7–10 days to target newly hatched insects.
What do lice look like and how can they be eliminated? - in detail
Lice are small, wing‑less insects measuring 2–4 mm in length. Adult bodies are flattened laterally, facilitating movement through hair shafts. Color ranges from gray‑white to brown, often darkening after a blood meal. Antennae consist of five segments, and each leg ends in a claw that grips hair. Nymphs resemble miniature adults, undergoing three molts before reaching maturity. Eggs, known as nits, are oval, 0.8 mm long, and firmly attached to the base of a hair strand with a cement‑like secretion; they appear white or yellowish and are difficult to detach without breaking the hair.
Detection relies on visual inspection of the scalp or body hair under adequate lighting. Live insects are mobile, moving quickly when disturbed. Nits are identified by their proximity to the scalp—typically within 1 cm of the skin—whereas shed shells are found farther away. A fine‑toothed comb can separate lice and nits from hair, allowing confirmation of infestation.
Elimination strategies include mechanical, chemical, and environmental measures:
- Mechanical removal: Use a nit‑comb with 0.2 mm teeth, combing each section of hair from scalp to tip. Repeat every 2–3 days for at least two weeks to capture newly hatched nits.
- Topical insecticides: Apply pediculicides containing permethrin (1 %) or dimethicone (4 %). Follow label instructions regarding application time and repeat treatment after 7–10 days to target emergent lice.
- Oral medication: In cases of resistance, prescribe ivermectin (200 µg/kg) as a single dose, with a possible second dose after one week.
- Environmental control: Wash bedding, clothing, and personal items in hot water (≥ 60 °C) and dry on high heat for at least 30 minutes. Seal non‑washable items in sealed plastic bags for two weeks to deprive lice of a host.
Consistent application of these methods, combined with thorough inspection, reduces the population to zero and prevents reinfestation. Regular monitoring for at least four weeks after treatment confirms successful eradication.