How long do clothing lice eggs live? - briefly
Clothing‑lice eggs (nits) hatch in roughly 7–10 days under normal conditions. After about two weeks, unhatched eggs lose viability and will not develop.
How long do clothing lice eggs live? - in detail
Lice eggs (nits) deposited on fabric remain viable for a limited period. After being laid, an egg requires a warm, humid environment to complete embryogenesis. On human scalp, optimal conditions allow hatching within 7–10 days. When the same eggs are transferred to clothing, the surrounding temperature usually drops below the threshold needed for development, and moisture evaporates quickly. Consequently, the eggs cease development and eventually die.
Key factors influencing survival on textiles:
- Temperature: Below 20 °C (68 °F) slows or halts embryonic growth; at 10 °C (50 °F) development stops entirely.
- Humidity: Relative humidity under 50 % reduces egg viability; drying out leads to desiccation.
- Exposure to sunlight: Ultraviolet radiation damages the egg shell, accelerating mortality.
- Mechanical disturbance: Washing, drying, or vigorous agitation removes or destroys eggs.
Under typical indoor conditions (20–22 °C, 40–60 % humidity), lice eggs on clothing can remain intact for up to 48 hours before they become non‑viable. If the garments are left untouched in a warm, moist environment, some eggs may survive up to 5 days, but hatching will not occur without a host scalp. Standard laundering—hot water (≥60 °C) and tumble drying—eliminates all viable eggs within one cycle.
In summary, lice eggs on apparel do not persist beyond a few days, and proper washing guarantees complete eradication.