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. Head-to-head contact is common during play at school, at home, and elsewhere sports activities, playground, slumber parties, camp. Although uncommon, head lice can be spread by sharing clothing or belongings.
This happens when lice crawl, or nits attached to shed hair hatch, and get on the shared clothing or belongings. Examples include:. The diagnosis of a head lice infestation is best made by finding a live nymph or adult louse on the scalp or hair of a person. Because nymphs and adult lice are very small, move quickly, and avoid light, they can be difficult to find.
Use of a magnifying lens and a fine-toothed comb may be helpful to find live lice. Nits are often confused with other things found in the hair such as dandruff, hair spray droplets, and dirt particles.
If you are not sure if a person has head lice, the diagnosis should be made by their health care provider, local health department, or other person trained to identify live head lice.
More on: Treatment. Most health departments do not require reporting of head lice infestation. However, it may be beneficial for the sake of others to share information with school nurses, parents of classmates, and others about contact with head lice. CDC is not a regulatory agency. School head lice policies often are determined by local school boards. Local health departments may have guidelines that address school head lice policies; check with your local and state health departments to see if they have such recommendations.
More on: Head Lice Information for Schools. Head lice should not be considered as a medical or public health hazard. Head lice can be an annoyance because their presence may cause itching and loss of sleep. Sometimes the itching can lead to excessive scratching that can sometimes increase the chance of a secondary skin infection. Head lice are spread most commonly by direct contact with the hair of an infested person.
Spread by contact with inanimate objects and personal belongings may occur but is very uncommon. Head lice feet are specially adapted for holding onto human hair. Head lice would have difficulty attaching firmly to smooth or slippery surfaces like plastic, metal, polished synthetic leathers, and other similar materials. Head lice and their eggs nits soon perish if separated from their human host. Adult head lice can live only a day or so off the human head without blood for feeding.
Nymphs young head lice can live only for several hours without feeding on a human. Nits head lice eggs generally die within a week away from their human host and cannot hatch at a temperature lower than that close to the human scalp. For these reasons, the risk of transmission of head lice from a wig or other hairpiece is extremely small, particularly if the wig or hairpiece has not been worn within the preceding 48 hours by someone who is actively infested with live head lice.
Data show that head lice can survive under water for several hours but are unlikely to be spread by the water in a swimming pool. Head lice have been seen to hold tightly to human hair and not let go when submerged under water.
Chlorine levels found in pool water do not kill head lice. Children should be taught not to share towels, hair brushes, and similar items either at poolside or in the changing room.
Is it possible to get head lice from sharing a pillow or hat with a person who has head lice? Lice cannot survive off of a human host longer than 24 hours and they are uniquely adapted for living in human head hair. They generally do not like to leave the protected environment created within head hair.
Head lice are most commonly found on the scalp, behind the ears and near the neckline at the base of the head. Symptoms include a tickling sensation, or feeling something moving through the hair. An allergic reaction to the bites causes itching. The adult louse is no bigger than a sesame seed and is grayish-white or tan.
Nymphs baby lice are smaller, and can be black, clear, or even blood red. Lice eggs, often called nits, look like tiny yellow, tan, or brown dots before they hatch. After hatching, the remaining shell looks white or clear. Nits are literally glued to the hair shaft and are very difficult to remove. Head lice do not jump, fly or swim.
They are good crawlers, however, and will readily move from one person to another when the hair of the two people is in contact. There are no reliable data to suggest that head lice carry or transmit disease organisms.
However, DNA technology shows head lice to be the same species as the notorious body louse which has long been associated with diseases such as typhus and relapsing fever. It may be possible for head lice to carry diseases, but no cases have been reported. Increasing numbers of consumers are finding that the most popular treatments for head lice — including chemical shampoos and home remedies — are largely ineffective.
Head lice are rapidly evolving chemical resistance to many of the traditional pesticide-based control methods [which have never been able to kill eggs nits effectively and usually require repeated treatments]. Louse combs can be effective for removing lice and eggs, but the comb-out process can be very tedious, and many busy parents do not have the time or patience for effective combing. In desperation, some parents resort to home remedies such as bug spray, mayonnaise or kerosene, but there is little hard evidence that these remedies are effective, and some home remedies can actually be harmful.
As a result, parents and school authorities are searching for a safe, fast and effective treatment that will solve the problem and help keep children in or quickly return them to school. Nymphs: Nymphs are immature lice that mature into adults about a week after hatching from the egg. If they come off the host, they die within 24 hours.
Female adult lice lay 4 to 8 eggs per day and can lay or more eggs during their lifetime. The eggs are glued to hair shafts, and hatch in days. It takes another days for the female louse to mature. She mates 24 hours later and starts laying eggs. There is not a difference although a nit is usually referred to as the empty shell and the egg as a viable egg. Sometimes people refer to one or the other in relation to its viability. Children, like adults, do not want nits in their hair- dead or alive.
The time it would take to make the distinction is time far better spent removing ALL the nits. Just because there is a louse inside does not confirm the fact that is was alive. Some products do have an ovicidal effect killing louse in the egg and some eggs are just laid and do not survive.
Head lice actually prefer a clean head of hair. Lice, however, are not prejudicial. To accomplish this, the louse needs to feed and is always looking for the most convenient means of doing so.
When lice are in water, they go into a state of suspended animation but remain firmly locked onto the hair. This is how they survive shampooing, rain, seawater, and swimming pools.
Risk of transmission will occur with the sharing of towels. What are some steps I can take to help prevent and control the spread of head lice? Avoid head to head contact during play, sleepovers, or other activities at home, school, and elsewhere. Do not share combs, brushes or towels used by an infested person.
Do not share clothing such as hats, scarves, coats, hair ribbons or barrettes. Machine wash and dry clothing, bed linens, and other items that an infested person used or wore during the previous 2 days using a hot water laundry cycle and high heat drying cycle. 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.
A magnifying glass and a bright light can help with your inspection. The best way to check is by using a fine-tooth comb on wet hair. After applying lots of conditioner, comb the hair out in very small sections, and look for lice or nits on the comb.
You can wipe the comb onto a tissue or paper towel where it will be easier to see them. If your child is itchy and scratching their head but you're not sure if it's lice, ask your child's doctor or the nurse at school or childcare center to take a look.
Medicine: Medicated shampoos, cream rinses, and lotions are available that kill lice. These may be over-the-counter OTC or prescription medicines. If you buy OTC, be sure it's safe for your child's age. While some over-the-counter shampoos are safe for kids as young as 2 months, others are safe only for kids 2 years and older.
In some areas, lice have developed resistance to some medicines. This means they no longer work to kill the lice. Ask your doctor or a pharmacist to recommend a medicine known to work in your area. The doctor also can prescribe a medicated shampoo or lotion. For very resistant lice, the doctor might recommend taking medicine by mouth.
Whether the medicine is OTC or prescription, always follow the directions closely. Applying too much can be harmful. Applying too little won't work. It is also an option for anyone who doesn't want to use an insecticide. And it is the only option for children 2 months old or younger, who should not use medicated lice treatment.
To do this, use a fine-tooth comb on wet, conditioned hair every 3—4 days for 3 weeks after the last live louse was seen. Wetting the hair temporarily stops the lice from moving, and the conditioner makes it easier to get a comb through the hair.
There's no need to buy electronic combs that claim to kill lice or make nits easier to remove. No studies have been done to back up these claims. You also don't need to buy special vinegar solutions to apply to the scalp before picking nits. Water and conditioner works fine. Though petroleum jelly, mayonnaise, or olive oil are sometimes used to try to suffocate head lice, these treatments may not work.
If medicine doesn't work and you want to try these methods, talk to your doctor first. A few important things to NOT do: Don't use a hairdryer after applying scalp treatments.
Some treatments for lice use flammable ingredients and can catch on fire. Don't use pesticide sprays or hire a pest control company to try to get rid of the lice; these can be harmful.
Don't use essential oils such as ylang ylang oil or tea tree oil to treat lice on the scalp. They can cause allergic skin reactions and aren't approved by the U. Don't ever use highly flammable chemicals such as gasoline or kerosene on anyone. Head lice spread quickly from person to person, especially in group settings like schools, childcare centers, slumber parties, sports activities, and camps. They can't fly or jump, but they have claws that let them crawl and cling to hair.
They spread through head-to-head contact, and sharing clothing, bed linens, combs, brushes, and hats. In the past, kids with head lice were kept home from school.
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