How many days pass since lice infection? - briefly
Head lice eggs typically hatch within 7‑10 days, and symptoms such as itching or visible nits appear by the end of the second week after exposure. Full adult populations can develop in about 9‑12 days from the initial infestation.
How many days pass since lice infection? - in detail
The period between the initial contact with head‑lice and the first visible signs typically spans several days. Female lice lay eggs (nits) within 24 hours of attachment; each egg hatches after about 7–10 days, depending on temperature and hair condition. Consequently, the earliest observable symptoms—itching caused by saliva injection and the presence of live lice—appear roughly one week after infestation.
A practical timeline:
- Day 0‑1: Adult female attaches, begins oviposition.
- Day 2‑4: Eggs mature but remain opaque; no symptoms.
- Day 7‑10: Eggs hatch; nymphs emerge, start feeding, causing mild itching.
- Day 10‑14: Population expands as nymphs mature into adults; itching intensifies, visible lice become common.
- Day 14‑21: Full infestation established; detection and treatment are most effective during this window.
Treatment should commence as soon as live lice or viable nits are confirmed. Effective products eliminate adults and prevent hatching, but a second application 7‑10 days after the first is recommended to target any newly emerged nymphs. Regular combing with a fine‑toothed lice comb every 2‑3 days for two weeks ensures removal of residual eggs and reduces the risk of re‑infestation.
Monitoring the timeline helps differentiate between a recent exposure and a mature infestation, allowing precise intervention and minimizing unnecessary repeat treatments.