What are lice nits? - briefly
Lice nits are the eggs laid by head lice, cemented to hair strands close to the scalp and visible as tiny, oval, white or yellowish shells. They hatch in roughly 7–10 days, releasing nymphs that mature into adult insects.
What are lice nits? - in detail
Lice eggs, commonly called nits, are the oval, translucent capsules that a female head‑lice deposits on a hair shaft. Each capsule measures about 0.8 mm, is firmly glued near the scalp, and contains a single embryo. The adhesive is a protein‑based cement that hardens within minutes, making the egg resistant to removal and to most shampoos.
The life cycle proceeds through three stages: egg, nymph, and adult. After an incubation period of 7–10 days, the embryo hatches, emerging as a nymph that resembles a miniature adult. Nymphs mature into reproductive adults after another 7–10 days, completing a cycle of roughly three weeks. Because a female can lay 6–10 eggs per day, infestations can expand rapidly if left untreated.
Key characteristics that differentiate nits from adult lice include:
- Position: nits are attached to the hair shaft within 1 cm of the scalp; adult lice move freely.
- Mobility: nits are immobile; adults are capable of walking and jumping.
- Appearance: nits appear as tiny, whitish‑gray ovals; adult lice are larger (2–4 mm), gray‑brown, and have six legs.
Identification relies on visual inspection of the hair close to the scalp, often using a fine‑toothed comb on a well‑lit surface. Viable nits are firm and opaque, while empty shells become brittle and turn more translucent after hatching.
Transmission occurs through direct head‑to‑head contact, which explains the prevalence among school‑aged children. Indirect spread via hats, brushes, or bedding is possible but less common because the cement loses its adhesiveness after the egg hatches.
Effective management combines chemical and mechanical strategies:
- Apply a pediculicide approved for lice treatment, following the product’s timing instructions to target both live insects and newly hatched nits.
- After the initial application, repeat treatment after 7–9 days to eliminate any lice that survived as eggs.
- Use a nit‑comb (metal or fine‑tooth plastic) on wet, conditioned hair to remove attached eggs; comb in sections from scalp outward, wiping the comb after each pass.
- Wash clothing, bedding, and personal items in hot water (≥ 50 °C) or seal them in airtight bags for two weeks to kill any surviving stages.
Prevention focuses on reducing head‑to‑head contact, avoiding sharing personal items, and conducting regular screenings in environments where infestations are common. Early detection and prompt, thorough removal prevent the spread and minimize the duration of an outbreak.