How long can lice live without air? - briefly
Lice can survive only a few minutes without breathable air, typically about five to ten minutes.
How long can lice live without air? - in detail
Lice are obligate ectoparasites that obtain oxygen through a pair of spiracles located on the thorax. Their respiratory system functions only while the tracheal tubes remain open to ambient air; when the insects are placed in an airtight environment, oxygen rapidly declines and carbon dioxide accumulates, leading to fatal hypoxia.
Experimental observations indicate the following survival limits in the absence of breathable air:
- In a sealed container at room temperature (20‑22 °C) and normal humidity, head‑lice (Pediculus humanus capitis) lose motility within 30 minutes and die completely after 2–3 hours.
- Body‑lice (Pediculus humanus corporis) exhibit a slightly longer tolerance, remaining active for up to 45 minutes and reaching mortality after approximately 4 hours under identical conditions.
- At lower temperatures (4‑10 °C), metabolic demand decreases; survival without oxygen can extend to 5–6 hours before irreversible damage occurs.
- High humidity (≥80 %) slows desiccation but does not significantly prolong the period of viable respiration; the limiting factor remains the depletion of oxygen.
The physiological basis for these limits is the low‑capacity tracheal system, which cannot store sufficient oxygen to support cellular metabolism beyond a few hours. Once the internal O₂ concentration falls below ~5 %, mitochondrial activity collapses, and accumulation of CO₂ to toxic levels (>10 %) triggers neuro‑muscular failure.
Consequently, lice cannot persist for more than several hours in an environment that completely lacks air exchange. Their survival time is governed primarily by temperature, humidity, and the initial oxygen reserve within their tracheal system.