How long do lice live on bedding? - briefly
Adult head lice can survive off a host for about 24 hours, rarely extending to 48 hours under optimal conditions; nymphs live a similar period, usually less than a day. Consequently, bedding remains a temporary habitat, losing viability within one to two days.
How long do lice live on bedding? - in detail
Lice can remain viable on mattresses, sheets, pillowcases, and blankets for a limited period after detaching from a host. Survival depends on species, temperature, humidity, and exposure to light.
- Adult head‑lice (Pediculus humanus capitis) survive up to 48 hours on dry fabrics when ambient temperature is 20‑25 °C and relative humidity exceeds 50 %. Lower humidity accelerates desiccation, reducing lifespan to 12‑24 hours.
- Body‑lice (Pediculus humanus corporis) exhibit similar tolerance but may persist slightly longer, up to 72 hours, because they are adapted to clothing environments. High humidity (≥70 %) extends survival to three days.
- Nits (eggs) are not viable off a scalp; they dry out within 24 hours and become non‑infectious.
Key environmental factors
- Temperature – Below 15 °C, metabolic activity ceases, and lice die within a few hours. Above 30 °C, dehydration occurs rapidly, limiting survival.
- Humidity – Moisture retains the insect’s cuticular water. Relative humidity below 30 % causes death in under 12 hours; above 70 % maintains viability.
- Light exposure – Direct sunlight degrades the exoskeleton and shortens lifespan by several hours.
Practical implications for control
- Immediate laundering of bedding at 60 °C (140 °F) or higher eliminates both adults and nits.
- Dry‑heat treatment (e.g., tumble dryer on high for 30 minutes) achieves the same result.
- Vacuuming removes detached insects; however, without heat or chemical treatment, survivors may re‑infest.
In summary, lice on bedding survive no longer than three days under optimal conditions, with typical survival ranging from half a day to one day in ordinary household environments. Prompt cleaning and heat exposure effectively eradicate the risk of reinfestation.