After hatching, the remaining shell looks white or clear and stays attached to the hair shaft. This is when it's easiest to spot them, as the hair is growing longer and the egg shell is moving away from the scalp.
Adult lice and nymphs baby lice. Adult lice are no bigger than a sesame seed and are grayish-white or tan. Nymphs are smaller and become adult lice about 1—2 weeks after they hatch. This life cycle repeats itself about every 3 weeks. Most lice feed on blood several times a day, and they can survive up to 2 days off the scalp. With lice bites come itching and scratching. This is due to a reaction to the saliva spit of lice. But the itching doesn't always start right away.
It depends on how sensitive a child's skin is to the lice. It might take weeks for kids with lice to start scratching. They may complain, though, of things tickling or moving around on their heads. Small red bumps or sores from scratching. Some kids have mild irritation from scratching, while others may get a bothersome rash.
Scratching a lot can lead to a bacterial infection. Watch for swollen lymph nodes glands on the back or front of the neck, and red, tender skin that might have crusting and oozing.
Doctors can treat a skin infection with an antibiotic. How Are Head Lice Treated? The two main ways to treat lice are: medicine removing by hand Medicine: Medicated shampoos, cream rinses, and lotions are available that kill lice.
Are Head Lice Contagious? Pets can't catch head lice and pass them on to people or the other way around. Can We Prevent Head Lice? To get rid of head lice and their eggs, and to help prevent them from coming back: Wash all bed linens, stuffed animals, and clothing used during the 2 days before treatment any lice that fell off before that will not be alive.
Dry clean items that can't be washed. Or put them in airtight bags for 2 weeks. Vacuum carpets and any upholstered furniture in your home or car , and throw away the vacuum cleaner bag. Soak hair-care items like combs, barrettes, hair ties or bands, headbands, and brushes in hot water or throw them away.
Although reliable data on how many people in the United States get head lice each year are not available, an estimated 6 million to 12 million infestations occur each year in the United States among children 3 to 11 years of age.
In the United States, infestation with head lice is much less common among African-Americans than among persons of other races, possibly because the claws of the head louse found most frequently in the United States are better adapted for grasping the shape and width of the hair shaft of other races. Head lice move by crawling; they cannot hop or fly.
Head lice are spread by direct contact with the hair of an infested person. Anyone who comes in head-to-head contact with someone who already has head lice is at greatest risk. Spread by contact with clothing such as hats, scarves, coats or other personal items such as combs, brushes, or towels used by an infested person is uncommon.
Personal hygiene or cleanliness in the home or school has nothing to do with getting head lice. Nits are firmly attached to the hair shaft and are oval-shaped and very small about the size of a knot in thread and hard to see. Nits often appear yellow or white although live nits sometimes appear to be the same color as the hair of the infested person.
Nits are often confused with dandruff, scabs, or hair spray droplets. Head lice nits usually take about 8—9 days to hatch. This is difficult to distinguish with the naked eye. Nymph: A nymph is an immature louse that hatches from the nit. A nymph looks like an adult head louse, but is smaller. To live, a nymph must feed on blood. Nymphs mature into adults about 9—12 days after hatching from the nit. Adult: The fully grown and developed adult louse is about the size of a sesame seed, has six legs, and is tan to grayish-white in color.
Adult head lice may look darker in persons with dark hair than in persons with light hair. To survive, adult head lice must feed on blood. Adult female head lice are usually larger than males and can lay about six eggs each day.
Head lice and head lice nits are found almost exclusively on the scalp, particularly around and behind the ears and near the neckline at the back of the head. Head lice or head lice nits sometimes are found on the eyelashes or eyebrows but this is uncommon. Head lice hold tightly to hair with hook-like claws at the end of each of their six legs.
Head lice nits are cemented firmly to the hair shaft and can be difficult to remove even after the nymphs hatch and empty casings remain. Head-to-head contact with an already infested person is the most common way to get head lice. It feeds on human blood from a person's scalp. Head lice crawl, but they can't jump or fly. Transmission of a head louse from one person to another is often by direct head-to-head contact, often within a family or among children who have close contact at school or play.
Indirect transmission is uncommon, but lice may spread from one person to another by items such as:. Indirect transfer could also occur among items of clothing stored together. For example, hats or scarves hung on the same hook or stored in the same school locker could serve as vehicles for transmitting lice. Because head lice are spread primarily by direct head-to-head contact, the risk of transmission is greatest among younger people who play or go to school together.
In the United States, cases of head lice most often occur in children in preschool through elementary school. If your child scratches an itchy scalp from a head-lice infestation, it is possible for the skin to break and develop an infection.
It's difficult to prevent the spread of head lice among children in child care facilities and schools because there is so much close contact. The chance of indirect transmission from personal items is slight. However, to help prevent a head-lice infestation, you may instruct your child to:.
A worry about head-lice transmission is not considered a good reason to avoid sharing protective headgear for sports and bicycling when sharing is necessary. Mayo Clinic does not endorse companies or products. Advertising revenue supports our not-for-profit mission. These include over-the-counter products, natural remedies, and prescription medications.
However, it is important to note that there are no natural or alternative products recommended by the CDC for the treatment of lice. Getting rid of lice completely involves three steps. No matter what kind of lice you have, the treatment process is essentially the same:.
The most common treatment product for lice involves pediculicide shampoo. After applying this treatment to the affected area, hair should not be washed for up to two days. You should thoroughly vacuum any area of your home where hairs might have fallen. Any bedding or clothing that has been exposed to the lice needs to be machine washed in hot water.
You may wish to avoid the use of lice medications on yourself or your small children. Some natural products promise the same results as pediculicides. A natural product that is not regulated may carry its own risks, especially in small children. Some studies have shown that essential oils may have a role in lice treatment. If you have lice, you may find relief with the following oils:. Lice seem to be building resistance to some commonly used products.
The American Council of Science and Health reports that in certain areas of the United States, traditional lice treatment products are no longer as effective at getting rid of infestations. There is no proven product or method that will completely eliminate the spread of lice, but there are steps you can take to lower your chances of getting it.
Avoid head-to-head contact with other people whenever possible. Never share personal hygiene products, especially combs or brushes. Tell your school-aged children about lice and the steps they can take to help minimize the risk of contracting it. Occasionally, an allergy to lice feces will lead to a rash and additional discomfort in the affected person.
Continuous scratching of an area to relieve itching can lead to breaking the skin barrier and, subsequently, an infection in that area. In rare cases, lice living on eyelashes can lead to eye inflammation and pinkeye.
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