The Facts of Lice

Also called Pediculul humanus capitis (peh-DICK-you-lus HUE-man-us CAP-ih-TUS), head lice are parasitic insects found on the heads of people. Having head lice is very common.

• Tickling feeling of something moving in the hair.
• Itching, caused by the allergic reaction to the bites.
• Irritability.
• Sores on the head caused by scratching. These sores can sometimes become infected.

Nits are more readily seen even though they are only about 1/16th of an inch long. They are most often found along the hairline at the back of the head and neck and behind the ears. The color of the nits is variable (white, grey, dark brown, or somewhat translucent). Nits should not be confused with an accumulation of hair spray, hair gels or dandruff. Dandruff can be easily flicked off the hair; nits cannot because they are firmly attached to individual hair.

There are three forms of head lice: the nit, the nymph, and the adult.
 

 
Nymph: the nit hatches into a baby louse called a nymph. It looks like an adult head louse, but is smaller. Nymphs mature into adults about 7 days after hatching. To live, the nymph must feed on blood.
 

• direct head contact with an infested person;
• sharing personal items such as combs, brushes, other hair-care items, towels and pillowcases;
• sharing clothing, headgear (hats, scarves, football and batting helmets, head phones, etc.), ribbons and other head coverings.

Shared school lockers and unassigned wall hooks for coats have been associated with higher rates of infestation than individual lockers. Even if schools have individual lockers, remember that there may be other times during the day when children's clothing comes together (e.g., throwing coats in a pile before or after recess).

How did my child get head lice?

• By contact with an already infested person.
• By wearing infested clothing such as hats, scarves, coats, sports uniforms, or hair ribbons.
• By using infested combs, brushes, or towels.
• By lying on a bed, couch, pillow, carpet, or stuffed animal that has recently been in contact with an infested person.

Treat the infested person/any infested family members:

Requires using an OTC or prescription medication. Follow these treatment steps:

• Before applying treatment, remove all clothing from the waist up.
• Apply lice medicine according to label instructions. If your child has extra long hair you may need to use an extra bottle.

WARNING: Do not use a crème rinse or combination shampoo/conditioner before using lice medication. Do not rewash hair for 1-2 days after treatment.

• Have the infested person put on clean clothing after treatment.
• If some live lice are still found 8-12 hours after treatment, but are moving more slowly than before, do not retreat. Comb dead and remaining live lice out of the hair. The medicine sometimes takes longer to kill the lice.
• If no dead lice are found 8-12 hours after treatment and lice seem as active as before, the medicine may not be working. See your health care professional.
• A nit comb should be used to remove nits and lice from the hair shaft. Many hair combs made for cats and dogs are also effective.
• After treatment, check hair every 2-3 days and use a nit comb to remove any nits or lice you see.
• Retreat in 7-10 days.
• Check all treated persons for 2-3 week after you think that all lice and nits are gone.

Treat the household:

• To kill lice and nits, machine wash all washable clothing and bed linens that the infested person touched during the 2 days before treatment. Use the hot water cycle (130° F) to wash clothes. Dry laundry using the hot cycle for at least 20 minutes.
• Dry clean clothing that is not washable, (coats, hats, scarves, etc.) OR
• Store all clothing, stuffed animals, comforters, etc., that cannot be washed or dry cleaned into a plastic bag and seal for 2 weeks.
• Soak combs and brushed for 1 hour in rubbing alcohol, Lysol®, or wash with soap and hot (130°) water.
• Vacuum the floor and furniture. Do not use fumigant sprays, they can be toxic if inhaled.

Here are some of those reasons:

• Misdiagnosis of head lice infestation.
• Not following treatment instructions fully.
• Medication not working at all (resistance).
• Medication kills crawling bugs, but is not able to penetrate the nits.
• New infection.