How are lice transmitted between people? - briefly
Lice spread mainly via direct head‑to‑head contact, allowing adult insects or nymphs to move onto a new host; they can also be transferred indirectly through shared items such as combs, hats, or bedding that harbor live lice or viable eggs.
How are lice transmitted between people? - in detail
Lice spread primarily through direct physical contact between individuals. Head lice (Pediculus humanus capitis) move from one scalp to another when heads touch, a common occurrence among children during play or close personal interaction. Indirect transfer occurs when contaminated objects—combs, brushes, hair accessories, hats, helmets, or headphones—contact a clean host. The insects survive up to 48 hours off‑body, allowing them to remain viable on shared items.
Body lice (Pediculus humanus corporis) transmit mainly via contaminated clothing or bedding. Eggs (nits) are laid on fabric fibers; when a person dons the infested garment, lice crawl to the skin to feed. Overcrowded living conditions, limited access to laundry facilities, and infrequent changing of clothes increase the risk of this route.
Pubic lice (Phthirus pubis) are transferred chiefly through sexual contact, as the insects inhabit the coarse hair of the genital region. They can also spread via close skin‑to‑skin contact involving other hairy areas, and rarely through sharing towels, bedding, or clothing that have come into contact with an infested area.
Key factors that enhance transmission:
- Prolonged head‑to‑head proximity
- Sharing personal grooming tools or headwear
- Wearing unwashed clothing or linens for extended periods
- Limited access to regular laundering or hygiene facilities
- Close sexual activity without barrier protection
Preventive measures focus on minimizing these exposure points: regular cleaning of personal items, frequent laundering of clothing and bedding at high temperatures, and avoiding head contact in settings where infestation is known. Early detection and prompt treatment interrupt the life cycle, reducing the likelihood of further spread.