Head lice are tiny brown, wingless insects, that live by sucking blood from the scalp. Their eggs, known as nits, are laid glued to the base of hairs, and look like tiny white specks. The eggs hatch after 7 to 10 days, and 10 to 14 days after hatching the nymph louse is mature and between 2 and 4 millimetres long. Once mature they can reproduce again so numbers can grow alarmingly if not treated. The head louse (Pediculus capitis) affects only humans, and cannot be passed on to, or caught from animals. Infestation is also known as pediculosis, named after the insect family Pediculidae. Head lice are common in schoolchildren, particularly between the ages 5 and 11, but anyone with hair can catch them.

Infestation often causes itching of the scalp, but may also go unnoticed. If you suspect head lice, check base of hairs for eggs and comb the hair over a piece of white paper to see if you can spot any dark mature lice.

Causes

Head lice are transferred by close hair-to-hair contact. They cannot jump or fly, but walk from one hair to another. It is a misconception that head lice infestation is a result of dirty hair and poor hygiene; in fact, head lice prefer clean hair and skin.

Treatment

Head lice are notoriously difficult to remove completely due to their size, reinfestation rate, life cycle, and their ability to develop immunity to insecticides. Lice can be a persistent and recurring nuisance, so vigilance in treatment is required. Once infestation is confirmed it can be treated at home either using wet combing with conditioner, or medicated shampoos, combined with a special nit comb available from pharmacies.

The Bug Buster Kit containing nit combs and treatment advice is produced by Community Hygiene Concern and recommended by the Department of Health for the wet combing method.

• wash the hair as normal
• apply conditioner liberally (this causes the lice to lose their grip on the hair)
• comb the hair through with a normal comb first
• with a fine tooth nit comb, comb from the roots along the complete length of the hair and after each stroke check the comb for lice and wipe it clean. Work methodically over the whole head for at least 30 minutes
• rinse the hair as normal
• repeat every three days for at least two weeks

Medicated shampoo

Ask your pharmacist for an over-the-counter insecticide shampoo or lotion. Apply the shampoo according to instructions, and remove the lice and eggs with a fine-toothed nit comb. Care should be taken when applying treatment because they are usually toxic. The normal advice is to treat once, and check for baby lice hatching 3-5 days after application. Repeat the process seven days later.

Always ask for advice before using insecticide medication on young babies (under 6 months), pregnant women or people with asthma and always read the instructions carefully.

There are complimentary therapy products such as tea tree oil which may also work.