Head Lice: How Do You Get It?

Lice don’t have wings, so they only crawl. However, they can be surprisingly fast. Here’s an overview of how lice spread — and what you can do to stop them.

Head lice spread by direct contact with an affected person’s hair. Kids will hug each other and literally put their heads together. You can’t completely prevent this, nor do many parents want to. But be cautious of any child who’s scratching their head constantly or who complains of an itchy head, and follow up with the school nurse or the child’s parents.

Head lice can also be spread by indirect contact with personal items that the affected person used:

• Hats, scarves, helmets, and caps shouldn’t be shared. Even shared lockers or coat racks can harbor head lice.
• Make sure your child has their own comb or brush.
• Make sure your child uses their own hair ties, barrettes, scrunchies, and hair pins and doesn’t borrow these from other children. Be open and honest with your kids — they don’t want head lice any more than you do.
• If your child is involved in a sport, make sure they have their own gear, and keep track of it. At the pool or gym, make sure your child has their own towels and other personal items.

A few signs of head lice may be noticeable right away, especially if your child doesn’t normally have these issues:

• excessive or abnormal itchiness on the scalp
• head scratching
• complaints of tickling sensations on the scalp
• bumps or irritation on the scalp from scratching
• trouble sleeping, as head lice are nocturnal and can be the most bothersome at night
• tiny yellow or tan dots on the shaft of the hair strands, which may be lice eggs (or nits)

You may not notice the symptoms of head lice right away. Head scratching is not uncommon for children, and some symptoms may take weeks to appear.

Head scratching and tiny white specks in the hair can also be symptoms of dandruff. Dandruff is a condition where dead skin cells flake off the scalp. But if your child rubs their hair and the specks don’t fall off the hair, you might be seeing nits.

As soon as you notice these symptoms, brush through your child’s hair with a comb, magnifying glass, and bright light to find and identify any nits or adult lice. While nits look like tiny dots, adult lice are about the size of a small seed and are usually tan or gray.

Once you’ve identified lice in your child’s hair, treat your child right away.

If your child appears to have a severe infestation, see a doctor to ask about the most effective course of treatment.

Over-the-counter treatments

If the infestation is mild, you can treat it at home with an over-the-counter treatment by doing the following:

1. Treat your child’s dry hair with a special liquid head lice medicine called a pediculicide. It’s available as a shampoo or lotion. Some options include pyrethrin, synthetic pyrethrin, or permethrin. Be sure to carefully read the instructions regarding age and usage requirements.
2. Have your child put on clean clothes once the treatment is finished.
3. Wait 8-12 hours to see if the lice and nits have been killed.
4. Use a nit comb (like a flea comb for dogs and cats) to get all the dead eggs and lice out of the hair.

Read more: Lice treatments and medications »

After the infestation has been stopped:

1. Check your child’s hair every few days to make sure no lice survived to lay more eggs.
2. Wet your child’s hair and comb through all of it from the scalp to the end of each section of hair. Use conditioner and a nit comb to remove any remaining dead eggs or lice.

You may need at least two bottles of the lice treatment if your child has long hair. You’ll most likely need to apply the medicine several times before the nits and lice are effectively treated.

Prescription treatments

If you still see lice moving around, try the treatment again and wait to see if the second treatment is effective. If you still see live lice, see your child’s doctor, especially if you’ve tried several over-the-counter treatments. They can tell you about prescription treatments like benzyl alcohol or malathion. Children who are at least 6 years of age can be treated with malathion, and children at least 6 months of age can be treated with benzyl alcohol.

Essential oils

You can also use essential oils in the hair, such as tea tree oil or nerolidol, to help kill lice and nits. You can also try smothering agents like olive oil and butter. These can be applied to the scalp and kept on the head overnight under a shower cap to kill the lice by suffocating them.

Avoid these

Never use any flammable treatments, such as kerosene, as these treatments can potentially be deadly. Don’t use any pet’s flea treatment shampoos. They haven’t been tested on children and may be unsafe to use.

It isn’t necessary to spray your home and belongings with potentially dangerous insecticides. Lice are “obligate parasites,” which means that they don’t survive very long without a human host. They die within 24 to 48 hours after being removed.

After you treat your child’s head and have removed all the nits, there are several recommended follow-up steps:

• Everyone in the household should change their clothing and bed linens. These items, as well as any hats, scarves, coats, and gloves, should be washed in hot water (at least 140^oF, or 60^oC) and dried with heat for at least 20 minutes.
• If something isn’t machine washable, take it to the dry cleaner. But first, warn the dry-cleaning staff about the article’s exposure to lice.
• Vacuum all chairs, sofas, headboards, and anything that may have come into contact with anyone’s head.
• Soak combs, brushes, and hair ties in a 10 percent bleach or 2 percent Lysol solution for one hour. You can also heat them in water as close to boiling as possible. You can also go out and get new combs, brushes, and hair ties, which may be a safer option.

If your child has reoccurring infestations, talk to your doctor about treatments or lifestyle changes that can help. Lice can sometimes develop a resistance to certain medications, so you may need to try several before you find the best treatment for head lice.

Head lice don’t cause any long-term health effects and are more annoying than harmful. Most of the time, they’re easily treated at home with over-the-counter medicine. They’re also easily prevented by practicing good hygiene, washing affected clothes and items after an infestation, and being cautious about sharing clothes, hats, brushes, or other items that come into contact with your hair.