ALl about

1. Introduction
There are many types of lice that infest animals and birds. However, only three types of lice infest humans. The most common are head lice which is the subject of this website. The second most common are pubic lice (crabs) which infest the genital area, and are usually spread by sexual relations. The least common are body lice, which are very similar to headlice in appearance, but are associated with poor hygiene, can live in soiled clothing & can carry disease such as typhus. 

The nuisance of headlice infestation occurs worldwide. It’s a very common infestation of all colours & classes of people. It usually occurs in children up to the age of about 12 years, but is easily transmitted from children to adults. Unfortunately, headlice infestation is not a transient or self-limiting condition. It needs to be treated to avoid advancement and to reduce the risk of transmission.  Prevention and home treatment is what this website is about. 

2. What are head lice?
Headlice, scientific name Pediculus humanus capitis, are wingless parasitic insects commonly found on human heads (& rarely on eyelashes, eyebrows and beard). Headlice are perfectly adapted to life on their human hosts. Their success is due to their small size (sesame seed), camouflage ability, prolific feeding and breeding habits, and ability to spread to new hosts by contact. With large claws on the ends on their six legs, headlice can quickly move along individual hairs to  feed, socialise, reproduce, and lay eggs - all on the head of their human host. 

3. What do head lice look like?
There are three stages of lice: the nit, the nymph, and the adult.

Nit: Nits are head lice eggs. In cooler climates they are laid very close to the scalp to use its warmth as an incubator. They are hard to see and are often confused with dandruff or hair spray droplets. Nits are found firmly attached to the hair shaft with a strong wax-like cement that also protects the maturing lavae. They are oval and usually yellow to white. Nits take about 1 week to hatch.

Nymph: The nit hatches into a baby louse called a nymph. It looks like an adult head louse, but is smaller. Nymphs mature into adults about 7 days after hatching. To live, they must feed on blood. Their colour depends on the colour of the hair on which they mature.

Adult: The adult louse is about the size of a sesame seed, has 6 legs, and is tan to greyish-white. In persons with dark hair, the adult louse will look darker. Females are usually larger than males, and outnumber them 4 to 1. Adult lice can live up to 30 days on a person’s head. To live, adult lice need to feed on blood from the scalp. If the louse falls off a person, it weakens and dies in about 1 or 2 days.

4. Where are head lice most commonly found?
On the scalp behind the ears, on the crown of the head and around the back of the neck. Headlice hold on to hair with hook-like claws found at the end of each of their six legs. Headlice are rarely found on the body, eyelashes, or eyebrows. They are not found on - nor caught from - pets or other animals. They can exist only if they obtain regular blood meals from human heads, which they extract like a mosquito or flea (but they don’t fly or jump...right?)

5. What problems do headlice cause?
Although no known diseases are transmitted, repeated headlice bites can cause an itchy skin reaction. Abrasions caused by repeated, prolonged or vigorous scratching may lead to secondary bacterial infection. Infestations may be distressing to sufferers and their families, causing anxiety and stress. In children this may lead to distractions from school work or exacerbate other conditions such as psoriasis, sleep disorders and rhinitis.

6. How do headlice feed?
Headlice feed only on a diet of human blood, about 5 times a day. Their retractable fangs penetrate the scalp and probe around to find a blood vessel. Before feeding, a head louse injects its saliva which contains an anaesthetic, anticoagulant and enzymes. These stop awareness of the bite, stop clotting of blood to enable easy withdrawal, and aid digestion. Digested blood is eventually passed as black powdery excreta which is loose enough to fall onto a pillow or over the face.

7. Who is at risk of getting head lice?
Anyone who comes in close contact with someone who already has head lice, contaminated clothing, shared hair-ware, etc. Children 3-10, and their families are infested most often. Girls get head lice more often than boys, women more than men. Social habits and hair length probably account for most headlice transferrals. Social or economic class, or hair cleanness make no difference to headlice. 

8. What can’t headlice do?
Headlice can’t fly because they have no wings, and their legs are not built to jump. The only way they can be passed on is by crawling during close head-to-head contact via a ‘hair bridge’. They can’t live in bedding, furniture, carpet, or clothes. They need to spend their life in contact with a human’s hair & scalp.

9. What are the signs and symptoms of infestation?
Often there are no symptoms. However, many people report:

• Tickling feeling of something moving in the hair. 
• Itching, caused by an allergic reaction to the bites.
• Irritability, and lack of concentration.
• Sores on the head caused by scratching. These sores can sometimes become infected. 
• Lice droppings: these show as black specs on pillow cases or collars.