Head Lice

Head Lice Life Cycle

Head Lice are small parasitic insects found most commonly near the neckline at the back of the neck and behind the ears. In scientific language, head lice infestation is known as ‘Pediculus humanus capitis’. A large number of people in the United States, especially children, are perturbed by head lice.

The Life Cycle of Head lice

The life cycle of Head lice is divided into three stages – the Nit, Nymph and Adult. The life cycle of a single louse from egg to egg is around 1 month.

Nits: The eggs of head lice are called nits. These nits are laid by the adult female louse at the base of the hair shaft. These nits are attached tightly to the hair shaft with strong cement. They are located very close to the hair scalp because they require body heat for incubation. The characteristics of nits are as follows:

• Size: The size of these nits is 0.8mm by 0.3mm
• Shape: Nits are oval in shape
• Color: Their color varies from yellow to white
• Location: Nits basically thrive within a range of 6mm of the scalp
• Duration: Nits take 6-9 days to hatch

Nymphs: When an egg hatches, it gives out a nymph. The shell of the nit stays compounded to the hair and then turns into a dull yellow color. It looks similar to an adult louse but is a bit smaller in size. As a nymph grows, it sheds out of its exoskeleton 3 times before it becomes an adult head lice.

Characteristics of Nymphs:

• Size: The size of a nymph varies, but is normally around the size of a pinhead
• Shape: It is similar to the adult louse
• Color: Yellow to rust-colored
• Location: A nymph inhabits close to the scalp, especially behind the ears and at the neckline
• Duration: Nymphs become adults after about 7 days

Adult: The adult louse feeds itself about 5 times a day by piercing the skin with its claws, injecting annoying saliva and sucking blood. Head lice grips the hair with the hook-like claws found at the end of each of their six legs. An adult Head lice is very active and can move quickly around the head.

The characteristics of adult lice:

• Size: It is as small as a pinhead. The male head lice is smaller than the female head lice
• Shape: An adult head lice is oval in shape and has 3 legs and claws at the end of each leg
• Color: Rust
• Location: A head lice lives close to the scalp especially behind the ears and at the neckline
• Duration: An adult lice can survive as long as 30 days on a person’s head
• Reproduction: It can lay up to eight nits per day.