Head Lice

Head lice is a parasitic insect that can be found on the head, eyebrows, and eyelashes of people.

Head lice survive by feeding on blood.

Head lice are a nuisance but do not spread disease.

IDPH Getting Rid of Head Lice: Simple 14-Day Treatment Schedule Brochure

What is Super Lice?

  • Super lice are head lice that have become resistant to some lice treatment products.
  • They look and act the same as 'regular' head lice (they are not bigger or faster)
  • Resistance to head lice treatments has been reported for decades and recent studies show the trend is continuing

What does head lice (including Super Lice) look like?

Head Lice: Egg Egg/Nits: These are the eggs laid by the adult female at the base of the hair shaft, nearest the scalp.
Head Lice: Nymp Nymp: This is the immature louse that hatches from the egg. It looks like the adult head louse, but is smaller.
Head Lice: Adult Adult: This is a fully grown, adult louse.  It is about the size of a sesame see, has six legs, and is tan to grayish-white in color.

How do head lice spread?

  • Head lice (including Super Lice) crawl - they do NOT hop or fly
  • Most spread is by head-to-head contact
  • Much less commonly, spread is through contact with clothing (scarves and hats) or other personal items (brushes and towels)

How long do head lice live?

  • Head lice (including Super Lice) live less than two days if they fall off a person and nits (eggs) will die if they are not kept at the same temperatures as that found close to the scalp.

What do you do if you (or someone in your family) have head lice?

  • Machine wash and dry clothing, bed linens, and other items that an infested person wore or used during the two 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 two weeks.

  • Vacuum the floor and furniture, particularly where the infested person sat or lay. Spending a lot of time and money on housecleaning activities is not necessary.

  • 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.

Why does treatment of head lice sometimes fail?

  • Applying the treatment to hair that has been washed with conditioning shampoo or rinsed with hair conditioner. Conditioners can act as a barrier that keeps the head lice medicine from adhering to the hair shafts; this can reduce the effectiveness of the treatment.
  • Not carefully following the instructions for the treatment that is used. Some examples of this include not applying a second treatment if instructed to do so, or re-treating too soon after the first treatment, before all the nits are hatched and the newly hatched head lice can be killed. Another reason is re-treating too late after new eggs have already been deposited.
  • Re-infestation. The person was treated successfully and the lice were eliminated, but the person becomes infested again by lice spread from another infested person. Sometimes re-shampooing the hair too soon (less than 2 days) after correctly applying and removing permethin can reduce or eliminate any residual (continued) killing effect on the lice.

Head Lice in School

  • Students diagnosed with live head lice do not need to be sent home early from school. They can go home at the end of the day, be treated, and return to school after proper treatment has started.
  • Personal hygiene or cleanliness in the home or school has nothing to do with getting head lice.

External Resource:

Centers for Disease Control and Prevention: Head Lice