Head lice are spread most commonly by direct head-to-head (hair-to-hair) contact. However, much less frequently they are spread by sharing clothing or belongings onto which lice have crawled or nits attached to shed hairs may have fallen. The risk of getting infested by a louse that has fallen onto carpet or furniture is very small. Head lice survive less than 1-2 days if they fall off a person and cannot feed; nits cannot hatch and usually die within a week if they are not kept at the same temperature as that found close to the scalp.
The following are steps that can be taken to prevent and control the spread of head lice:
- Avoid head-to-head (hair-to-hair) contact during play and other activities at home, school and elsewhere (sports activities, playground, slumber parties, camp).
- Do not share clothing such as hats, scarves, coats, sports uniforms, hair ribbons or barrettes.
- Do not share combs, brushes, or towels. Disinfest combs and brushes used by an infested person by soaking them in hot water (at least 130°F) for 5-10 minutes.
- Do not lie on beds, couches, pillows, carpets or stuffed animals that have recently been in contact with an infested person.
- Machine wash and dry clothing, bed linens, and other items that an infested person wore or used during the 2 days before treatment using the hot water (130°F) laundry cycle and the high heat drying cycle. Clothing and items that are not washable can be dry-cleaned OR sealed in a plastic bag and stored for 2 weeks.
- Vacuum the floor and furniture, particularly where the infested person sat or lay. However, spending much time and money on housecleaning activities is not necessary to avoid re-infestation by lice or nits that may have fallen off the head or crawled onto furniture or clothing.
- Do not use fumigant sprays or fogs; they are not necessary to control head lice and can be toxic if inhaled or absorbed through the skin.
To help control a head lice outbreak in a community, school or camp, children can be taught to avoid activities that may spread head lice.
Symptoms of Infestation
The itching that occurs when lice bite and suck blood from the scalp is a primary symptom of infestation, although not everyone will experience the itching. Children seen scratching their heads frequently or intensely should be examined.
What to look for
Lice are small, (about the size of a sesame seed) wingless insects. They have 6 legs equipped with claws to grasp the hair. They are clear in color when they are hatched, and then quickly develop a reddish-brown color after feeding. They move very quickly and shy away from light, making them difficult to see. Diagnosis is more often made on the basis of finding the nits (eggs) that are laid by the adult female louse. Nits (eggs) are small yellowish-white, oval-shaped eggs that are “glued” to the side of the hair shaft at an angle. They do not move like dandruff or lint/debris in the hair. Nits may be found throughout the hair at any distance from the scalp, but are most often located at the nape of the neck, behind the ears and frequently on the crown. It helps to use natural light and a magnifying glass or reading glasses when looking for them.