How do lice jump onto another person? - briefly
Head lice move only by crawling; they transfer to a new host when heads touch or when hair and clothing are shared. They lack the ability to jump or fly.
How do lice jump onto another person? - in detail
Lice move between hosts primarily through direct head‑to‑head contact. Adult females lay eggs (nits) close to the scalp; when a person with an infestation touches another’s hair, the insects crawl onto the new host within seconds. The insects lack the ability to jump or fly; locomotion relies on six legs equipped with tiny claws that grip hair shafts. Contact can occur during:
- Close physical interaction (e.g., hugging, sharing helmets, scarves, or hats).
- Transfer of combs, brushes, or hair accessories that have insects or nits attached.
- Use of bedding, towels, or upholstered furniture that has recently harbored lice, though this route is less efficient because the insects quickly die without a host.
The crawling speed of a head louse averages 0.5 cm per minute, sufficient to reach the scalp after initial contact. Environmental conditions such as temperature (around 30 °C) and humidity (70‑80 %) enhance survival and mobility, allowing the insects to remain active long enough to locate a suitable host. Once on a new scalp, lice immediately begin feeding on blood, reproduce, and continue the cycle of transmission.