How does a person acquire lice? - briefly
Lice are transferred primarily by direct head‑to‑head contact or by sharing personal items—hats, combs, hair accessories—that have recently touched an infested scalp.
How does a person acquire lice? - in detail
Lice infestations begin when viable nymphs or adult insects transfer from an infested host to a new one. Transfer occurs through direct head-to-head contact, which places the insects’ claws on hair shafts and allows them to crawl onto the new scalp. Indirect transmission can happen when personal items—combs, brushes, hats, helmets, hair accessories, or bedding—retain live lice or freshly hatched nymphs; handling these objects creates a pathway for the parasites.
Key mechanisms include:
- Physical proximity: Close, sustained contact between individuals, especially in crowded environments such as schools, camps, or sports teams, raises the probability of transfer.
- Shared equipment: Items that remain in contact with hair for extended periods serve as reservoirs; lice survive up to 48 hours off a host, making recent use a risk factor.
- Environmental persistence: While lice cannot live long on surfaces, eggs (nits) glued to fabric or hair remnants can remain viable for several days, enabling re‑infestation after initial removal.
Transmission likelihood rises with certain behaviors: frequent head rubbing, swapping of caps or scarves, and insufficient cleaning of personal belongings. Preventive measures focus on minimizing direct contact, avoiding the exchange of hair‑related objects, and regularly laundering fabrics at high temperatures to destroy any lingering stages of the parasite.