How long can head lice stay in clothing? - briefly
Head lice can remain viable in fabric for up to 48 hours, with most individuals dying after about 24 hours without a host. Washing garments in hot water (≥ 130 °F) or sealing them in a plastic bag for two days eradicates any surviving insects.
How long can head lice stay in clothing? - in detail
Head lice (Pediculus humanus capitis) cannot feed without direct contact with a human scalp. On fabrics, they survive only as inactive organisms, and their longevity depends on temperature, humidity, and exposure to sunlight.
Typical survival estimates:
- At room temperature (20‑25 °C) and moderate humidity (50‑60 %), adult lice remain viable for 24‑48 hours.
- In cooler environments (below 15 °C), metabolic activity slows, extending survival up to 72 hours.
- High humidity (above 80 %) can marginally increase viability, but not beyond three days.
- Direct sunlight or heat above 30 °C accelerates desiccation, reducing survival to less than 12 hours.
Eggs (nits) are more resistant. Under similar conditions, they may remain viable for up to five days, but hatch only when transferred to a scalp.
Practical implications for garment handling:
- Wash clothes, bedding, and hats in hot water (≥60 °C) and tumble‑dry on high heat; this eliminates both lice and nits.
- If washing is unavailable, seal items in a plastic bag for at least 72 hours; lack of a host will cause death.
- Dry cleaning is effective, as solvents remove lice and eggs.
Regular inspection of personal items, combined with prompt laundering, prevents re‑infestation from clothing.