The head louse is a parasite that is scientifically called the Pediculus Humanus Capitisi, which is found on the head of 
humans and some animals. These parasites are quite known to be living in the hair on the head of humans and those found at the neck. It is important that you differentiate this head louse from the pubic louse, which inhabits the pubic hair, and the body louse, which lives on other parts of the body.
Body Structure
The head louse almost looks similar to a very small ant. This insect is quite the same as other arthropod insects as it has a head, a thorax, and an abdomen. The normal color of the parasite is white and has six legs in front of the body.
Life of a Head Louse
The female head louse is that insect that will lay eggs called the nits in the area just above the scalp. These eggs are white or gray white and can sometimes be mistaken for dandruff. The normal; span for the eggs to hatch would be around seven to nine days. The female parasitic insects will lay around three to seven eggs per day in a month. If the eggs do not hatch properly, they appear dry and will have a dark shade of color.
The head louse would have three stages until it grows into a full parasite. These stages are the nit, the nymph and adult louse. The nit is the eggs of the lice that attaches itself to the hair shaft and are sometimes mistake to be dandruff. The second stage is the nymph or childhood stage, and the louse appears similar to the adult. The only difference is that the nymph is smaller than the adult head louse. In just seven days, the nymph will grow into a full adult head louse.
Human blood is the primary source of food for the head louse. The nymphs would usually attach to the scalp and will suck the blood out from the head. The sizes of the female lice are slightly larger than the males. Once these parasites fall off and attach to other surroundings similar to hair, they will eventually die as they longer have the nourishment to support their system.
Contagious Mode of Living
The head louse is a contagious parasite that will eat away on the blood of humans. These parasites do not have the ability to fly, but they can still rapidly spread from one person to another. Group settings and situations are the ideal conditions to spread the head lice to other people. They would usually cling to hair products such as combs and brushes. When used by others, they would transfer to that person and breed on that new area. Head to head contact is the process by which the head louse will spread.
