Do Lice Eggs Roll Down Hair Shafts?

Head lice (Pediculus capitis) are small, six legged insects that live on human heads. They are light brown to yellow in color, and can also be referred to as a "louse." An adult louse can lay up to 6 eggs (nits) per day, and about 100 in its life cycle.

Viability

• According to the University of Rhone Island Horticulture program, "Most lice that fall off the hair will not usually survive longer than two to three days, while nits can remain viable for up to 14 days off the human host. Human lice are not transmitted by pets such as dogs, cats, gerbils, birds, etc--these lice do not survive on domestic animals."

Nits

• Nits are oval in shape and are about the size of a period. They range in color depending on their life cycle phase from shiny brown, to yellowish, to translucent white.

Nit-Picking Barriers

• What makes lice in and of itself, such a difficult infestation to get under control, is that lice eggs are actually glued to the hair shaft when they are laid. Therefore, no amount of shampooing and shaking of the head will release a lice egg from its hair shaft. Additionally, most of the over-the-counter treatments kill only the live lice, leaving the eggs still viable and ready to hatch. That is why manual egg removal is the most important process.

Nit Removal

• Some of the store bought lice combs cannot successfully detach a nit from a strand of hair. Cut and immediately dispose of the strands of hair with nits attached.

Modes of Transmission

• Lice spread from person to person, usually as a result of direct contact. The sharing of hats, combs and hairbrushes, may also transmit lice.