What are head lice?
Head lice are small, usually pale- to grey-colored insects that live and reproduce in the hair on human heads. Head lice feed on human blood and can survive only on people. Their oblong eggs (called “nits”) are usually tan- or brown-colored but can appear whitish under bright lights. They are about 1 to 2 mm long and attach to the hair close to the scalp. The nits hatch after about 1 week then pass through 3 stages (over 1 to 2 weeks) before becoming full-sized adults that are about the size of a sesame seed. One female produce about 6 or 7 eggs a day during her life span.
How do you get them?
Head lice move between people when their heads have direct contact. Lice cannot fly or jump from one person to another but may move from one person to another by sharing objects such as combs, brushes, hats or towels. Head lice do not survive for very long when not on a person. Infestations are much more common in school-aged children than in adults.
What are the symptoms of head lice?
The first “symptom” may be seeing the lice or their eggs. Louse feeding may cause the scalp to itch. However, the amount of itching can vary from being a nuisance or causing severe scratching that breaks the skin. Other symptoms may include: - a tickling feeling or a sensation of something moving in the hair; - irritability and sleeplessness; and - sores on the head caused by scratching. These sores caused by scratching can sometimes become infected with bacteria normally found on a person’s skin. Head lice do not transmit diseases.
When do symptoms start?
Head lice infestations can be asymptomatic. Itching (called "pruritus") is the most common symptom of head lice infestation and is an allergic reaction to louse bites. It may take 4-6 weeks for itching to appear the first time a person has head lice.
Should a person with head lice stay away from work or school
Yes, until they are properly treated. A person with head lice should limit their contact with others for 24 hours after starting effective treatment.
For how long is a person contagious?
A person is contagious as long as they have live lice in their hair.
What is the treatment for head lice?
Very careful examination and combing, using a nit comb, can be an effective method to eliminate head lice. Medicated hair treatments can control head lice and should be used when live lice are found in the hair.
How do you keep from getting it?
Reduce the risk of catching head lice by avoiding both direct head-to-head contact and close sharing of items that might accidentally transfer lice (hats, brushes, etc.). For more information, see the CDC’s website at http://www.cdc.gov/parasites/lice
