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Illustration of head lice

Also called: Pediculosis

Head lice are parasitic wingless insects. They live on people's heads and feed on their blood. An adult is called a louse and is about the size of a sesame seed. The eggs, called nits, are even smaller - almost like a dandruff flake. Lice and nits are easiest to detect at the neckline and behind the ears.

Head lice are extremely contagious. Close contact or sharing personal belongings, such as hats or hairbrushes, puts people at risk. Children ages 3-11 and their families get head lice most often. Personal hygiene has nothing to do with getting head lice.

Symptoms are

  • Tickling feeling in the hair
  • Frequent itching
  • Sores from scratching

The most important step in treating head lice is to treat the person and other family members with medicine to kill the lice.

Centers for Disease Control and Prevention

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  • Head Lice(Centers for Disease Control and Prevention)
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