Overview

Lice are tiny, wingless, parasitic insects that feed on your blood. Lice are easily spread — especially by schoolchildren — through close personal contact and by sharing belongings.

There are three types of lice:

• Head lice. These lice are found on your scalp. They're easiest to see at the nape of your neck and over your ears.
• Body lice. These lice live in clothing and on bedding and move onto your skin to feed. Body lice most often affect people who aren't able to bathe or launder clothing regularly, such as homeless or transient individuals.
• Pubic lice. Commonly called crabs, these lice occur on the skin and hair of your pubic area and, less frequently, on coarse body hair, such as chest hair, eyebrows or eyelashes.

People can have good personal hygiene and still get lice. Unless treated properly, this condition can become a recurring problem.

Source: http://www.mayoclinic.com

Symptoms

Signs and symptoms of lice include:

• Intense itching.
• Tickling feeling from movement of hair.
• Lice on your scalp, body, clothing, or pubic or other body hair. Adult lice may be about the size of a sesame seed or slightly larger.
• Lice eggs (nits) on hair shafts. Nits resemble tiny pussy willow buds. Nits can be mistaken for dandruff, but unlike dandruff, they can't be easily brushed out of hair.
• Small red bumps on the scalp, neck and shoulders.

When to see a doctor

Usually you can get rid of lice by taking self-care steps that include using nonprescription shampoo that's specifically formulated to kill lice.

However, see your doctor if:

• Nonprescription shampoo doesn't kill the lice — your doctor can prescribe a stronger, prescription shampoo
• You're pregnant — don't use any anti-lice shampoo until you talk to your doctor
• You have any infected hives or skin abrasions from scratching

Source: http://www.mayoclinic.com

Causes

You can get lice by coming into contact with either lice or their eggs. Eggs hatch in about one week. Lice can't fly or walk on the ground. They spread through:

• Head-to-head or body-to-body contact. This may occur as children or family members play or interact closely.
• Proximity of stored belongings. Storing infested clothing in closets, in lockers or on side-by-side hooks at school, or storing personal items such as pillows, blankets, combs and stuffed toys in proximity at home can permit lice to spread.
• Items shared among friends or family members. These may include clothing, headphones, brushes, combs, hair decorations, towels, blankets, pillows and stuffed toys.
• Contact with contaminated furniture. Lying on a bed or sitting in overstuffed, cloth-covered furniture recently used by someone with lice can spread them. Lice can live for one to two days off the body.
• Sexual contact. Pubic lice usually spread through sexual contact and most commonly affect adults. Pubic lice found on children may be a sign of sexual exposure or abuse.

Source: http://www.mayoclinic.com

Diagnosis

During an examination, your doctor may look for lice using a magnifying lens and check for nits using a special light, called a Wood's light, which makes the nits look pale blue.

Head lice

A diagnosis of head lice can be made after a live young or adult louse in the hair or on the scalp is found, or after one or more nits is seen on hair shafts located within 1/4 inch (6.4 millimeters) of the scalp.

If you don't see any live lice or you see nits that are more than 1/4 inch away from the scalp, the infestation is probably no longer active. Nits should be removed to prevent a recurrence.

Body lice

A diagnosis of body lice may be made if eggs or crawling lice are found in the seams of clothing or on bedding. It's possible to see a body louse on skin if it crawls there to feed.

Pubic lice

Pubic lice are diagnosed when moving lice or nits are seen on hair in the pubic area or on other areas of coarse hair, such as chest hair, eyebrows or eyelashes.

Source: http://www.mayoclinic.com

Prevention

It's difficult to prevent the spread of head lice among children in child care and school settings. There's so much close contact among children and their belongings that lice can spread easily. It's no reflection on your hygiene habits or those of your children, and it's not a failure on your part as a parent if your child gets head lice.

Some over-the-counter products claim to repel lice, but more scientific research is needed to prove their safety and effectiveness.

A number of small studies have shown that ingredients in some of these products — mostly plant oils such as coconut, olive, rosemary and tea tree — may work to repel lice. However, these products are classified as "natural" so they aren't regulated by the Food and Drug Administration (FDA), and their safety and effectiveness haven't been tested to FDA standards.

Until more research proves the effectiveness of head lice prevention products, the best approach is simply to take thorough steps to get rid of the lice — and their eggs — so that you don't have more lice to deal with.

• Ask your child to avoid head-to-head contact with classmates during play and other activities.
• Instruct your child not to share personal belongings such as hats, scarves, coats, combs, brushes, hair accessories and headphones.
• Instruct your child to avoid shared spaces where hats and clothing from more than one student are hung on a common hook or kept in a locker.

However, it's not realistic to expect that you and your child can eliminate all the types of contact that may result in the spread of lice.

Your child may have nits in his or her hair but not necessarily develop a case of head lice. Some nits are empty eggs. However, nits that are found within 1/4 inch (6.4 millimeters) of the scalp should be treated — even if you find only one — to prevent the possibility of hatching.

Nits that are farther away from the scalp are probably from an old infestation, but should be removed to prevent a recurrence.

Alternative medicine

A number of home or natural remedies, such as mayonnaise or olive oil, are used to treat head lice infestations, but there's little to no evidence of their effectiveness.

For parents looking at alternative treatment methods, at least two have weak evidence supporting their use. However, more research is needed. For the first, you apply the over-the-counter cleanser Cetaphil to the hair and scalp, dry it with a hair dryer, and then leave it overnight and wash it out in the morning. Repeat this treatment once a week for three weeks.

The other is a special machine that uses hot air to dehydrate head lice and their eggs. The machine requires special training and is currently available only at professional lice treatment centers.

A regular hair dryer can't be used to do this at home as it's too hot and could burn the scalp. The machine at the clinics uses air that is cooler than most hair dryers but at a much higher flow rate to kill the lice by drying them out.

Source: http://www.mayoclinic.com

Lifestyle and home remedies

You can get rid of lice with a patient, thorough approach that involves cleaning yourself or your child and any personal belongings that may be contaminated.

These steps may help you eliminate lice infestations:

• Check other household members for lice and nits. Treat anyone who has signs of an infestation.

• Use lotions and shampoos. Choose from among several over-the-counter lotions and shampoos (Nix, Rid, others) designed to kill lice. Apply the product according to package instructions.

  You may need to repeat treatment with the lotion or shampoo in about nine days. These lotions and shampoos typically aren't recommended for children under age 2.

• Comb wet hair. Use a fine-toothed or nit comb to physically remove the lice from wet hair. Repeat every three to four days for at least two weeks. This method may be used in combination with other treatments and is usually recommended as the first line treatment for children under age 2.
• Wash contaminated items. Wash bedding, stuffed animals, clothing and hats with hot, soapy water — at least 130 F (54 C) — and dry them at high heat for at least 20 minutes.
• Seal unwashable items. Place them in an airtight bag for two weeks.
• Vacuum. Give the floor and furniture a good vacuuming.
• Wash combs and brushes. Use very hot, soapy water — at least 130 F (54 C) — or soak combs and brushes in rubbing alcohol for an hour.

One thing you don't need to worry about is your household pets. Lice prefer people to pets, so your pets don't need any treatment for lice.

Source: http://www.mayoclinic.com