Head lice are tiny, flat, wingless insects that live and feed on blood from the human scalp. These insects are about 2mm long, range in colour from light brown to grey, and are commonly found in people’s hair.
Adult female lice can lay about 7 to 10 eggs (nits) per day and may live up to 1 month. These eggs hatch in about a week and the lice mature to adulthood over the next 7 days. When away from a host, head lice can survive for about 2 to 4 days.
Contrary to popular belief, head lice do not jump or fly from one person to another. Instead, they are spread by direct contact with an infected person and their belongings (e.g. brushes, combs, hair accessories, caps, towels, blankets, pillows and stuffed toys).
Head lice are common among school children because they tend to share personal belongings and also spend time in close contact with each other. Pets do not transmit head lice, and lice can infect both dirty and clean hair. Therefore, its presence is not a reflection of poor personal hygiene.
The diagnosis of head lice is usually made by finding nits attached to hair shafts. Nits are tiny, white, oval eggs that look like dandruff but cannot be shaken off the hair easily.
Live lice move quickly so they are seldom seen. However, their red bite marks and nits can often be found along the back of the head and neck, as well as behind the ears where the skin is warmer. A common symptom is an intense localised itch on the head that is caused by substances in the lice saliva. This itch may continue for 1 week even after the lice infestation has been cleared.
Over the counter products available in Singapore for head lice treatment include:
Malathion Shampoo or Lotion -
A pediculicide which affects the lice nervous system.
Repeat treatment once per week until all the lice are killed.
Do not use for longer than 3 consecutive weeks.
Consult a doctor for advice before using if pregnant or breastfeeding.
Disadvantage: Flammable, not safe for use in children under 6 months of age.
Benzoyl Benzoate Lotion -
Another pediculicide which affects the lice nervous system.
Leave the medicine on the affected areas for 24 hours before rinsing.
Olive Oil -
A smothering agent that blocks the holes on the sides of lice to stop their breathing.
Advantage: Few allergies, inexpensive.
Triple Action Lice Comb -
A comb with narrow and extra-narrow spaced, round-tipped teeth to give 3 times the
Non-slip for easy, comfortable combing.
Works on all hair types and style.
After treating the head lice, additional steps should be taken to prevent re-infection or spreading of the infection to other people:
- Treat all close contacts and family members who may be infected.
- Check for, and remove nits in bright light (preferably in the day under the sun).
- Remove all dead lice and nits with a fine-toothed comb (lice comb), tweezers, or fingernails.
- Dip the lice comb in vinegar before combing it through the hair. Vinegar helps loosen up the nits by making them less sticky.
- Disinfect all brushes, combs, and hair accessories in a lice shampoo solution, soapy water, or alcohol for an hour or soak in very hot water (65 °C) for about 10 minutes.
- Wash all recently worn clothing and used bed linens, pillow cases, and towels in hot water, and dry them in a hot dryer for at least 20 minutes. Dry clean or iron any items that cannot be washed.
- Seal stuffed toys and other non-washable items in a plastic bag for 2 weeks or place them in the freezer (in sealed plastic bags) for 12 to 24 hours. The lice will die because they will have nothing to feed on.
- Cover furniture with a plastic cover for 2 weeks.
- Vacuum all carpets, rugs, mattresses, pillows, furniture, and car seats to remove lice and eggs.
- Consult a doctor if there are signs of bacterial infection on the scalp.