Head Lice Fact Sheet

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Head lice are small insects

They live on the hair, eyebrows, and eyelashes of humans where they feed and lay eggs. Eggs take about 7-10 days, and may be up to 14 days to hatch. To live, adult lice need to feed on blood. If the lice fall off a person, then they will die within 2 days. The adults’ life span is approximately one month, and eggs can survive on clothing for a month.

Anyone can get head lice

It is common in school-age children.  You can catch head lice by coming in direct contact with an infested person's head or with personal belongings such as combs, brushes, and hats. Head lice can spread as long as lice or eggs remain alive on the infested person or clothing.  Dogs and cats do not catch head lice.

Itching of the head and neck is common with head lice

Itching may be mild to intense.  Rarely, irritated skin from head lice can get infected with bacteria.  Signs of such bacterial infection include fever, swollen neck lymph glands, and hot, red skin.

Head lice are diagnosed by the presence of adult lice or eggs

Lice may be difficult to see.  They are most commonly seen at the nape of the neck and behind the ears.  Nits (eggs) may be seen as specks "glued" to the hair shaft. Nits range in color from yellow to grey.

A person infected with head lice can be treated

Medicated shampoos or creme rinses kill lice.  Some medications also kill nits. Permethrin‑based medications (such as Nix) are the treatment of choice and may be purchased over‑the‑counter. Follow package directions closely.  Removal of nits is recommended in addition to proper medication.  Fine‑toothed combs are available to help remove nits from hair. A second course of therapy is sometimes needed.

•    Spraying classrooms or homes with insecticides is not recommended.
•    Vacuum floors, rugs, pillows, and upholstered furniture.
•    Wash hats, scarves, clothing, towels and bed linen in hot water (130°F) and dry using high heat for at least 20 minutes.
•    Dry clean or tie up non‑washable items in a plastic bag for 2 weeks.
•    Combs and brushes can be washed with medicated shampoo or soaked in hot water (130°F).

•    Avoid direct contact with an infested person’s hair.
•    Do not share combs, brushes, hats, scarves, ribbons, or other personal items.
•    Household members and close contacts of a person with head lice should be examined and treated if they are infested.

Maryland Department of Health & Mental Hygiene 
Epidemiology & Disease Control Program
April 2008

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