Head lice survive less than one or two days if they fall off the scalp and cannot feed. Head lice eggs (nits) cannot hatch and usually die within a week if they do not remain under ideal conditions of heat and humidity similar to those found close to the human scalp.
But unfortunately, the nits will not simply fall out your hair. The lice themselves take 7 to 11 days to hatch, so after that what is attached to the hair is the empty eggshell or the dead nit. These will stay attached to the hair and as the hair grows you will find them further and further down the hair shaft.
Off the host, adult head lice can live about two to four days at 74 degrees Fahrenheit (F) and one to two days at 86 degrees. Nits will remain alive off the host for up to 10 days; they will not hatch at or below room temperature (68 degrees F).
As with furniture and carpets, adult lice typically live for around 2 days on pillows and sheets without human contact. Nits will not hatch and will die within a week. People should machine wash any pillows or sheets someone with lice has used in hot water of more than 130°F (54.4°C) .
The proportion of lice killed varied from 10% with the bonnet‐style hair dryer to 80% with the Louse‐Buster with hand piece.
After each treatment, checking the hair and combing with a nit comb to remove nits and lice every 2–3 days may decrease the chance of self–reinfestation. Continue to check for 2–3 weeks to be sure all lice and nits are gone.
Can someone have nits but no lice? It may be possible to have nits but no lice. If a person cannot find any nymphs or adult lice in the scalp and the nits are more than a quarter of an inch from the scalp, these may be dead and from an old infestation.
You shouldn't see any crawling head lice after the first treatment if you applied it correctly. If you are still seeing live crawlers, then you may have missed a step or the treatment is not effective against the type of lice your child has.
There are no over-the-counter or prescription treatments that totally kill both lice and nits. Nits cannot be washed out or brushed out of the hair. They must be picked or pulled out with a special nit comb or by hand. Various natural remedies exist for treating lice but there is no scientific proof that they work.
Shaving the head does not cure lice. The itching should go away within a few days, but the medicated treatment will need to be repeated in 5 to 7 days to kill any new lice that may have hatched since the first treatment.
Coconut, tea tree oil, lavender, eucalyptus, rosemary, lemon grass, and peppermint are scents popularly believed to repel lice. Using any coconut scented shampoo and conditioner is an easy way to increase your defense. At 1% concentration, tea tree oil killed 100% of head lice after 30 minutes.
Head lice nits usually take about 8–9 days to hatch. Eggs that are likely to hatch are usually located no more than ¼ inch from the base of the hair shaft.
It is important that all members of the family with symptoms of an infestation are treated. It is also important to wash bedding, clothing and towels. Treatment involves using prescription or over-the-counter medicine to kill the lice.
New eggs are attached to the hair shaft very close to the scalp. Eggs that still contain a louse embryo are brownish in color, while the empty egg shells are white to grey.
In fact, it can take up to six weeks for a child or adult to develop the typical itchiness that might prompt a head check. And even then, half the people with lice still won't exhibit any symptoms associated with lice.
Vinegar contains properties that kill and get rid of nits and lice. This mixture should be applied directly to the whole scalp. Mix 1 cup of vinegar with 1 cup of warm water. Next, distribute this mixture onto the scalp and cover your hair with a hair cap.
The only way to prevent them from hatching would be to remove them with a good metal nit comb, or your fingernails. Nits are laid by the mother and attached with a glue she formulates, to sit on the hair shaft in the perfect spot to incubate and hatch.
Washing clothes in hot water (>60°C) for >10 min kills clothes lice and their eggs (30).
A buzz cut is not going to solve the problem. Head lice can live and lay nits in even ¼” of hair, so a buzz cut isn't an effective lice treatment. In fact, a buzz cut can actually make the head lice removal process more difficult. That's because with a buzz cut, the short hairs stand straight up.
Tea tree oil works by repelling lice because of its insecticidal properties. In addition to keeping the hair tied up and artificially dirty, you can use tea tree oil to repel a head louse looking for a new home. You may also include lavender essential oil or peppermint essential oil for this purpose.