How long can lice live on a pillow? - briefly
Head lice can survive on a pillow for roughly one to two days, extending up to five days only under optimal humidity and temperature conditions.
How long can lice live on a pillow? - in detail
Lice can remain viable on a pillow for a limited period because they require human blood to survive. Adult head‑lice typically survive 24–48 hours without a host; under warm, humid conditions this can extend to about 72 hours. In cooler, drier environments their lifespan shortens to roughly 12–24 hours. Body lice, which are more tolerant of temperature fluctuations, may persist up to five days, but still cannot feed and will die once energy reserves are exhausted.
Eggs (nits) attached to pillow fibers are more resilient. At optimal temperature (around 30 °C) and relative humidity above 70 %, an egg can hatch within seven to ten days, provided it later contacts a host. If conditions fall below 20 °C or humidity drops under 50 %, embryonic development stalls and the egg will not hatch, eventually dying.
Key factors influencing survival on bedding:
- Temperature: 20–30 °C maintains metabolic activity; lower temperatures accelerate mortality.
- Humidity: 60–80 % preserves moisture; dry air desiccates insects rapidly.
- Access to a host: No blood intake leads to exhaustion of stored nutrients within 1–3 days for adults.
- Egg placement: Nits glued to fabric are protected from environmental stress but still require suitable conditions to develop.
Practical implications:
- Immediate laundering of pillowcases in hot water (≥60 °C) and drying on high heat eliminates both adults and viable eggs.
- Vacuuming and steam cleaning remove detached insects and reduce humidity, shortening survival time.
- Replacement of heavily infested pillows is advisable because residual eggs may remain embedded in the fabric.
Overall, without a human host, lice on a pillow survive no more than three days under typical indoor conditions, while their eggs may persist longer but will not hatch unless favorable temperature and humidity are restored.