Head lice infestations can occur wherever children congregate and anyone can get them. Parents should check their child(ren) for head lice regularly. If lice or eggs are found, refer to the information provided below.
Pediculus humanus capitis, a louse.
Head lice are very small (less than 1/8" long, about this size [--]), brownish-colored insects that live on human heads and lay their eggs (nits) close to the scalp. The eggs are tiny (about the size of the eye of a small needle) and gray or white in color. Adult lice move quickly and do not like light.
If your child is experiencing itching of the head and neck, look for:
- crawling lice in the hair, usually few in
- eggs (nits) glued to the hair, often found behind the ears and at the
of the neck, and
- scratch marks on the head or back of the neck at the hairline.
Lice do not jump or fly; they crawl and can fall off the head. Lice do not spread to or from pets. Lice are spread by close head-to-head contact during events such as sport activities, scouts, slumber parties, other play activities and by sharing personal items such as:
- combs, brushes, barrettes;
- hats, scarves, sports head gear;
- blankets, sheets, pillowcases;
- stuffed animals, and
- play activity clothes.
Incubation and Viability
Head lice only lay their eggs while on the head, and it takes 7-10 days for the eggs to hatch.
which are more than ½" from the scalp are dead or empty and will not hatch. Eggs will not hatch if they fall off the head. Head lice do not live
longer than 48 hours off the head and do not spread to or from pets.
A person with head lice is contagious until treated with a lice treatment product.
Exclusion from Childcare and School
Children with head lice should not congregate with others until the first treatment is completed and no live lice are seen.
Nits are NOT considered live lice.
- Call a healthcare provider or pharmacist for advice. Recommended treatment
includes using either an over-the-counter (OTC) or prescription (lice
killing) product. Use products that contain permethrin or a pyrethrin-based
shampoo. For the most current head lice treatment guidelines please refer to the Center for Disease Control website.
- Follow the product directions carefully (especially the amount of product to
use, length of time on the hair, and whether to use on dry or damp hair).
Directions will vary, depending on the product used.
DO NOT clean or wash hair immediately prior to applying any type of lice medication to the hair and scalp. Hair should not be washed for 1-2 days after lice treatment.
- With certain products a second treatment is recommended 7 to 10 days later to
kill any lice that may have hatched after the first treatment.
- It may take 24 hours for products to kill lice.
- Lice treatment products are not 100% effective in killing lice, especially nits.
Removing the nits (nitpicking) is an essential part of the treatment for
controlling the spread of head lice. The nits are glued onto the hair shaft as
they are laid and require effort to remove. To remove the nits, use a metal nit
comb, cat flea comb, or your fingernails to slide eggs off the hair shafts, or use
scissors to cut the hair shafts that have nits glued to them. Continue checking
the head and combing hair daily for two weeks. If all nits within ½" of the scalp
are not removed, some may hatch and the child will be infested again.
Remember: it takes at least two weeks to get rid of lice.
- Check all household members for head lice. Treat only household members
with head lice, and treat all at the same time.
- Many alternatives to OTC or prescription head lice control products have been
suggested. Although there is little scientific evidence to support these
treatments, people often use alternative treatments when the usual treatments
have not worked or when there is concern about the toxicity of repeated use of
head lice control products. Some of the treatments being used include applying
mayonnaise, oils (vegetable, olive, mineral, etc.), or petroleum jelly (Vaseline)
to the head. These materials may suffocate and/or make it hard for the lice to
move but do not kill the nits. Some of these products are very difficult to
remove from the hair.
- DO NOT share combs, brushes, other hair grooming items and other hair
accessories (barrettes, etc.), towels, bedding, clothing, hats, and headgear, such
as personal headphones and sports helmets.
- Parents should check their child's head regularly for head lice.
- Sleepovers are a common setting in which head lice are spread.
When a child returns from a sleepover, check the child's head and launder any
bedding that they brought home.
- Clean all combs, brushes, other hair grooming items and accessories (barrettes,
etc.) by doing one of the following:
- soaking in the lice treatment product for 10 minutes;
- cleaning with hot soapy water, or
- boiling for five minutes.
- Vacuum carpets, upholstered furniture, mattresses, and seats in the car(s)
thoroughly. Insecticide sprays are NOT recommended because this will
expose household members to unnecessary pesticides and most viable lice are
found on the head, not in the environment.
- Wash clothing worn in the last three days (e.g., jackets, hats, scarves, pajamas),
bedding, and towels in hot (130 degrees Fahrenheit or higher) water and dry in a hot dryer for at
least 20 minutes before using again. Clothing or backpacks that cannot be
washed or dried, linens, and stuffed toys can be dry cleaned or sealed in plastic
bags for two weeks.
How to Remove Nits
Work in a well-lit room or under a bright lamp (using a magnifying glass may help you see the nits).
- Divide the hair into four parts and divide each part into 1-inch sections.
- Starting at the scalp, use a metal nit comb, cat flea comb, or your fingernails
to comb each hair section individually.
- Use the comb or your fingernail to slide eggs off the hair shaft or use scissors
to cut hair shafts that have nits glued to them.
- Remove all nits each time you comb the hair.
- REMEMBER: it can take at least two weeks to get rid of lice.
For more information, call your school nurse or visit the Centers for Disease Control and Prevention.
Information on this page was adapted from:
- Hennepin County Human Services
- Public Health Department (HSPHD)
- National Association of School Nurses (NASN)
- Center for Disease Control (CDC)