Head Lice

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What are head lice?

Head lice are tiny insects, the size of a sesame seed, that live on the human head. Their color varies from tan to grayish white. They do not jump or fly, but crawl from hair to hair and feed on blood several times a day. Head lice are found on the scalp, eyebrows, and eyelashes of people. Adult lice, eggs (nits), and nymphs (immature lice) are often found around and behind the ears and near the neckline at the back of the head.

Who can get head lice?

Anyone can get head lice regardless of their personal hygiene practices. Head lice are very contagious.  A person with head lice can spread them until all of the lice and nits are destroyed. Head lice are most common in pre‐school and elementary school age children and household members of infested individuals.

How do you get head lice?

Head lice can be passed from one person to another in a number of ways:

  • Head‐to‐head contact.
  • Sharing items like combs, brushes, towels, bedding, hats, helmets, coats, scarfs, ribbons and barrettes, and stuffed animals.
  • Placing heads on furniture, rugs, pillows, or car seats recently used by someone with lice.

What are the signs & symptoms of head lice?

  • Lice on the scalp. Lice are difficult to spot because they're small, avoid light and move quickly.
  • Nits near the scalp, stuck on hair shafts. Nits may also be difficult to see because they're very tiny and can be mistaken for dandruff. Empty nits may be easier to spot because they're lighter in color and farther from the scalp.
  • Tickling feeling of something moving in the hair.
  • Itching, caused by an allergic reaction to the bites of head lice.
  • Irritability and difficulty sleeping; head lice are most active in the dark.
  • Sores on the head caused by scratching.

Do head lice spread disease?

Head lice do not spread illness or disease and are not considered a public health hazard. Skin infections may occur from scratching the bites.

Is there a treatment for head lice?

There are several prescription and over‐the‐counter head lice products available through your healthcare provider or drugstore.

  • Before applying treatment, it may be helpful to remove clothing that can become wet or stained during treatment.
  • Do not use a combination shampoo/conditioner or conditioner before using lice medicine. Do not re–wash the hair for 1–2 days after treatment.
  • Apply lice medicine, according to the instructions contained in the box or printed on the label. If the person has very long hair (longer than shoulder length), it may be necessary to use two bottles. Pay special attention to instructions on the label or in the box regarding how long the medication should be left on the hair and how it should be washed out.
  • Have the infested person put on clean clothing after treatment.
  • Nit combs, often found in lice medicine packages, should be used to comb nits and lice from the hair shaft. Many flea combs made for cats and dogs are also effective. Put removed lice and nits directly in a lined trash container and discard immediately after treatment.
  • If a few live lice are still found 8–12 hours after treatment, but are moving more slowly than before, do not re-treat. The medicine may take longer to kill all the lice. Comb dead and any remaining live lice out of the hair using a nit comb.
  • After 8–12 hours of treatment, if no dead lice are found and lice seem as active as before, the medicine may not be working. Speak with your health care provider; a different treatment may be needed.
  • After each treatment, check the hair and comb with a nit comb to remove nits and lice every 2–3 days. Continue to check for 2–3 weeks to be sure all lice and nits are gone. Check the head of each family member and close contact daily as well.   
  • Re-treatment is meant to kill any surviving lice before they produce new eggs. Re-treatment may be recommended about a week after the first treatment (7–9 days).

Cleaning steps

  • Disinfest combs and brushes used by someone with head lice by soaking them in hot water (at least 130°F) for 5 – 10 minutes.
  • Machine wash and dry clothing, bed linens, car seat covers, and other items that someone with head lice wore or used during the 2 days before treatment using the hot water (130°F) laundry cycle and the high heat drying cycle.
  • Clothing and items that are not washable can be dry-cleaned OR sealed in a plastic bag and stored for 2 weeks.
  • Vacuum the floor and furniture, particularly where the person with head lice sat or lay. Spending much time and money on housecleaning activities is not necessary to avoid reinfestation.
  • Do not use fumigant sprays or fogs; they are not necessary to control head lice and can be toxic if inhaled or absorbed through the skin.

How do I avoid Head Lice?

  • Avoid head-to-head (hair-to-hair) contact during play and other activities at home, school, and elsewhere (sports activities, playground, slumber parties, camp).
  • Do not share clothing such as hats, scarves, coats, sports uniforms, hair ribbons, or barrettes.
  • Do not share combs, brushes, or towels.
  • Do not lie on beds, couches, pillows, carpets, or stuffed animals that have recently been in contact with someone with head lice.
  • Regularly check your child's head for lice.

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