About Head Lice

What are Head Lice?
The head louse is a parasite which lives on the human scalp, feeding on human blood. The "bite" made to suck the blood does not hurt, but the substance the louse excretes to prevent the blood from clotting can cause itching and allergic reactions. Lice have a lifespan of 40 days, during which each lays about 200 eggs (also called nits), attaching one egg per strand of hair with a very strong natural "glue". Most of these hatch within seven to ten days. Given the average growth rate of hair, by the time the egg hatches it is located about 5mm (about 1/5 of an inch) from the scalp.

Who gets Head Lice and how are they transmitted?
Children up to the age of 12 are the most susceptible to head lice, but it does affect older children as well. Since lice transfer easily from one head to another through physical contact or sharing clothing, hats or brushes, they are easily contracted by children in schools, day care centers, camps and similar locations. Once thought to be primarily a "back to school" problem, head lice have now become a year-round issue.

Life Cycle of the Lice (from the CDC)
The life cycle of the head louse has three stages: egg, nymph, and adult.
Eggs: Nits are head lice eggs.  They are hard to see and are often confused for dandruff or hair spray droplets.  Nits are laid by the adult female and are cemented at the base of the hair shaft nearest the scalp.  They are 0.8 mm by 0.3 mm, oval and usually yellow to white.  Nits take about 1 week to hatch (range 6 to 9 days).  Viable eggs are usually located within 6 mm of the scalp.
Nymphs: The egg hatches to release a nymph.  The nit shell then becomes a more visible dull yellow and remains attached to the hair shaft.  The nymph looks like an adult head louse, but is about the size of a pinhead.  Nymphs mature after three molts and become adults about 7 days after hatching.
Adults: The adult louse is about the size of a sesame seed, has 6 legs (each with claws), and is tan to grayish-white.  In persons with dark hair, the adult louse will appear darker.  Females are usually larger than males and can lay up to 8 nits per day.  Adult lice can live up to 30 days on a person’s head.  To live, adult lice need to feed on blood several times daily.  Without blood meals, the louse will die within 1 to 2 days off the host.

Do many people actually suffer from head lice?
Yes. In the United States , roughly six million cases are reported annually by school nurses. Experts believe that the problem is under-reported, and that in fact there may be as many as 20 million cases each year. Many children suffer from recurring infestation, or re-infestation, which can happen when returning to a classroom or similar situation where an ongoing problem exists. Many schools will not allow children back into a classroom until their head lice is gone, creating significant hardship for both child and parents.

How do you treat head lice?
There are a variety of ways to treat head lice - topical medications, Lice & Egg Removal Shampoos, Egg & Lice Combs, and with the Robi Comb - a new electronic comb. In addition, many experts recommend treating clothing and bed linens to help prevent re-infestation.

Detect & Destroy

Currently there is only one device that both detects and destroys lice in dry hair- the Robi Comb.

The Robi Comb is a small (3" x 2 ¾") comb with metal coated teeth, powered by a single AA battery. As the comb slides through a child's hair, it makes a soft humming sound until it encounters a louse. At that time, the sound stops and a small electrical charge passes from one of the comb's teeth through the louse to the next tooth, zapping the louse. This is an easy and fast way to detect lice on dry hair. The zapped lice are also destroyed in the process. Using the small brush included in the Robi-Comb package, the user removes the dead louse from the comb's teeth and resumes combing. Find out more about the Robi Comb.

Remove Lice & Eggs

Removal of lice and lice eggs (also called nits), is an important part of the lice treatment process. Because nits hatch up to ten days after being laid, their continued presence in the hair can lead to an ongoing infestation even after treatment with a "lice killing shampoo". Using Robi-Comb, one can deal with this issue by combing every day for 10 days, killing the lice as they hatch until there are no more eggs left to hatch. Another way to quickly remove lice and lice eggs, is by using a Lice & Egg Shampoo and then Combing the lice and eggs out of the hair. There are a number of lice shampoos on the market, which can be divided into two groups- Toxic and Non-Toxic.

Toxic Shampoos
The most common method for removing lice and eggs until now has been the use of topical medications usually in the form of a Toxic Shampoo, whose active ingredients include pesticides such as Pyrethrum or Permethrin. These chemicals are poisons that attack the louse's nervous system. While these medications have long been considered effective, they can damage the mucous membranes of the eyes, nose, and mouth. (This can occur accidentally, or the pesticide can be absorbed through wounds on the scalp caused by scratching, since head lice can cause itching of the scalp.)

Recently, many parents and school nurses have shared concerns that head lice are developing resistance to pesticides, and have reported treatment failures using pesticide based products. Scientific studies in the US and other countries have reported pesticide-resistant head lice. After seven to ten days, the pesticide shampoos recommend a second application to insure that as the eggs hatch they are destroyed. (Pesticides are generally not terribly effective on the young eggs, as they have no central nervous system for the chemical to attack.)

Non-Toxic Shampoos
Another alternative is a non-toxic shampoo such as LiceGuard's SAFE Lice Egg Removal Shampoo - although it does not kill lice, it does make egg removal much easier. It has an original formula that softens and untangles the hair and has been shown to be very effective in removing nits. In a clinical trial, LiceGuard SAFE Lice Egg Removal Shampoo removed 85% of the nits in one group of children after just five minutes of combing with a fine-toothed comb, compared to only 25% of the nits when LiceGuard SAFE Lice Egg Removal Shampoo was not used.

Other hair treatments such as olive oil, petroleum jelly, mayonnaise and a variety of other natural remedies have also been reported.

Lice and Egg Combs
Use of a hair treatment or shampoo should be followed by the proper use of a Egg & Lice Comb.Very fine-toothed metal combs should be used to remove lice and nits. This treatment must be performed on wet hair. After lice eggs have been loosened, the Egg & Lice Comb pulls them off the hair.

Prevent Lice

LiceGuard Lice Repellent Spray helps protect a child from head lice by preventing the transfer of lice from other infested children. Sprayed and combed through a child's hair once in the morning, the repellent works all day. Its patented, water-based formula (proprietary fragrance RB-1) is a mixture of non-toxic substances which are safe for daily use and cause no irritation to the skin or eyes.

In clinical and laboratory studies conducted in England, France, Israel and the United States, LiceGuard Lice Repellent Spray was shown to provide up to 85% protection from the spread of head lice. In Israel, a study was done on 82 children in a school where 30% of the children had head lice. For five weeks, 40 children used LiceGuard Spray daily. A control group of 42 children was treated with a placebo (water). At the end of the five weeks, none of the 40 children treated daily with LiceGuard Spray had become infested, while 30% of the children treated with the placebo were infested with head lice. The pediatrician conducting the study confirms the results prove that daily use of LiceGuard Head Lice Repellent Spray helps prevent the transfer of head lice from one child to another.

If lice are found or suspected, adults should also do a careful cleaning of all items in the home. Hats, coats, scarves and bed linens should be machine washed in hot water and dried in the hot cycle for 20 minutes or more. Articles which are not washable should be dry-cleaned and placed in a sealed plastic bag for about two weeks. Brushes and combs should be disinfected by soaking in very hot water. Thorough vacuuming a child's room and play areas is also suggested. Lice need to feed a number of times a day, so they cannot live for long periods away from a human host. Taking the above suggested steps will help end the possibility of re-infestation, caused by lice located on a household item, waiting to "hitch a ride" on another head.