How do lice appear? - briefly
Lice originate when adult females deposit eggs, called nits, on hair shafts near the scalp. The eggs hatch in 6–9 days into nymphs, which undergo three molts before attaining reproductive maturity.
How do lice appear? - in detail
Lice become detectable when adult females deposit eggs (nits) on hair shafts close to the scalp. The eggs hatch after 7‑10 days, releasing nymphs that resemble miniature adults. Nymphs undergo three molts over approximately 9‑12 days, each stage increasing in size and mobility. Mature lice emerge fully formed, capable of feeding on blood and reproducing.
The infestation cycle proceeds as follows:
- Egg laying: a female lays 5‑10 eggs per day, securing each to a hair strand with a cement‑like substance.
- Hatching: embryonic development completes within a week, producing a mobile nymph.
- Molting: three successive molts occur, each lasting 2‑3 days, during which the nymph grows and gains feeding efficiency.
- Reproduction: adult females begin oviposition after about a week of maturity, sustaining the population.
Transmission typically occurs through direct head‑to‑head contact, allowing mobile lice to migrate onto a new host. Indirect spread via shared personal items (combs, hats, bedding) is less common but possible when eggs remain attached to objects and later contact a scalp. Environmental conditions such as warm, humid settings favor survival and rapid population growth.
Effective control requires interruption of the life cycle: removal of eggs, elimination of live lice, and prevention of re‑infestation. Regular inspection, thorough combing with a fine‑toothed device, and appropriate topical treatments reduce the likelihood of recurrence.