Lice Facts

What are Head Lice?

Head lice are tiny 2-4 mm wingless insects. They cannot fly or jump, but they can crawl./ 24 hours after mating, female head lice lays her eggs (nits) on the hair shaft about ¼ inch away from the scalp, although they can be found anywhere on the scalp.

Lice can live up to a month and can lay up to 10 eggs a day.

Baby lice (nymphs) are almost transparent. In a week they will mature and become grayish white to reddish brown. Once mature, they will mate and start laying eggs again.

What are nits?

Nits are poppy seed sized eggs attached at an angle to the hair shaft. They can be yellowish or grayish white ovals, most often found near the ears and at the nape of the neck.

Symptoms

• Itching
• Red bite marks on scalp
• Tickling feeling of something moving through hair
• Less common are sores caused by scratching which may become infected.

Who is at risk?

• Anyone who has had head to head contact with infected people.
• Sharing hats, combs, or personal items like towels that belong to an infected person.
• Preschool and school age children 3-11, and their siblings and parents.
• Hygiene is immaterial to head lice, they enjoy clean and dirty hair equally

How can I tell if what I'm seeing is really a nit?

Cut the hair and look at the nit closely. It would be difficult to remove, tear drop shaped, and yellowish white or tan. Most scalp particles will flake off - eggs do not move.

How do I remove lice with shampoo?

Over the counter pesticide shampoos will kill live lice, but children under the age of 2, people with asthma, allergies, seizures, pregnant and breastfeeding women should consult their doctors before applying these shampoos. These shampoos do not kill the eggs under the age of 4 days, so manual removal is still the most important step in eradicating all lice.

The National Pediculosis Association believes that mechanical removal with a comb is the safest and most effective way to remove nits and lice. Combing removes both nits and lice when done correctly, but hair must be dampened with conditioner to immobilize the live lice.

Why are lice so hard to get rid of if they sell shampoos that claim to do that?

Lice preparations kill only 50-70 % of nits. If all the nits are not removed they will hatch into crawling lice, generating a cycle of self re-infestation.Most people mistakenly believe one application of an over the counter shampoo will be enough to control the infestation. Unfortunately, that is not the case.

According to Harold George Scott, Ph.D., Board Certified Entomologist, "Resistance is a reflection of populations undergoing selection to produce survival of the fittest. Resistance does not occur all at once. It develops over time in louse populations, so, in any particular location, both resistant and nonresistant populations may exist. This can cause much confusion, because pediculicides that work one day fail to work the next." Therefore, relying on pediculicides alone may fail to eliminate head lice.

More and more lice are growing resistant to Nix, Rid, and typical permethrine-based treatments. Mechanical nit removal is the only way to prevent reinfestation.