Where can lice live besides the head? - briefly
Lice can inhabit body hair—including pubic, facial, armpit, and chest hair—and may persist briefly on clothing, bedding, or upholstered furnishings, allowing re‑infestation of a human host.
Where can lice live besides the head? - in detail
Lice that are not confined to the scalp occupy a limited range of environments that provide direct contact with a host, warmth, and protection for egg deposition.
The most common non‑scalp species is the body louse (Pediculus humanus corporis). Adult insects reside in the seams of clothing, especially in tight‑fitting garments such as underwear, socks, and work uniforms. Eggs (nits) are attached to fabric fibers, where they remain viable for several days before hatching. The insects emerge only to feed on the host’s blood, typically at night, and return to the garment for shelter.
Pubic lice (Pthirus pubis), often called crab lice, inhabit coarse hair in the genital region, but they also colonize other body sites that contain similar hair types: the axillae, chest, abdomen, beard, moustache, eyebrows, and eyelashes. Eggs are cemented close to the skin surface, and the insects stay on the host continuously, moving only when transferred during close contact.
Head lice (Pediculus humanus capitis) occasionally appear on facial hair, eyebrows, and eyelashes, especially in children with dense hair in those areas. While the scalp remains their primary niche, these secondary locations provide comparable conditions for feeding and reproduction.
Animal‑specific lice demonstrate similar habitat preferences. For example:
- Cattle lice (Haematopinus irritans) live on the hide, particularly in the neck, dewlap, and udder folds.
- Sheep lice (Bovicola ovis) occupy the wool and skin folds.
- Dog and cat chewing lice (Trichodectes spp.) cling to the fur on the head, neck, and back, laying eggs on hair shafts.
All lice require a host for survival; off‑host viability rarely exceeds 24–48 hours, and they cannot establish colonies on inanimate surfaces without a living host. Consequently, their distribution outside the head is limited to body regions that supply constant warmth, moisture, and a blood source.