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.
Generally, if no live crawling insects are seen three weeks after the treatment, it's safe to assume that they are gone. Nits would have hatched by that time if they were alive. Nits and their shells may remain in the hair for some time but won't be viable.
Nits may remain after lice have gone. They are empty eggshells and stick strongly to hair. They will eventually fall out. If you prefer, a fine-toothed 'nit comb' can remove them.
Most treated nits (lice eggs) are dead after the first treatment with Nix. The others will be killed with the 2nd treatment. Removing the dead nits is not essential or urgent. However, it prevents others from thinking your child still has untreated lice.
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.
If you do not comb out all the remaining nits, they will hatch and restart the cycle in 7-10 days from that point. That's why we recommend 3 treatments over a 12-day period of time. This stops the life cycle of lice. These are nits at different stages and a louse.
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.
Nits are often confused with other things found in the hair such as dandruff, hair spray droplets, and dirt particles. If no live nymphs or adult lice are seen, and the only nits found are more than ¼-inch from the scalp, the infestation is probably old and no longer active and does not need to be treated.
Lice and nits can live on pillows and sheets. Lice glue their eggs to the hair strands of their host. However, if a piece of hair with an egg falls out while the lice host is sleeping, an egg could end up on pillows or sheets.
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.
How soon do symptoms appear after exposure? Some people may not have symptoms, particularly with the first infestation or when the infestation is light. It may take 4-6 weeks for itching to appear the first time a person has head lice.
Can you go to work if you have head lice? Unless your employer has a 'no-nit' policy, then there is no reason you cannot go to work if you have head lice. There is no guidance saying children should be kept off school if they have head lice,3 so the likelihood of your employer wanting you to stay off work will be low.
After Treating with Lice Medicine
Check for lice again in 8 to 12 hours. Use the nit comb to remove dead lice and nits. If some are still present but moving slowly, do not shampoo again. If lice are still active and no dead lice are found, call your health care provider.
If you leave head lice untreated, the symptoms of lice infestation will worsen. The lice will continue to feed on the scalp, spreading from person to person, and the itching and discomfort will become more severe. As the lice population grows, so will the amount of eggs they lay, raising the risk of reinfestation.
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.
Adult head lice can survive for 2 days and nits for around 1 week on a hairbrush. Soaking combs or hairbrushes in hot water of at least 130°F (54.4°C) for 5–10 minutes will kill any lice and nits.
How many head lice are usually found on an infested person? Typically, 10–15 head lice are found. The number of lice often depends on personal hygiene, for example, how often the person bathes, shampoos, or changes and washes his/her clothing.
Dead nits are often black in colour and are found well away from the scalp. Nits are laid on the hair shaft within 1cm of the scalp and take about 7-10 days to hatch into head lice.
Head lice check in dry hair
Lice move in dry hair and they may therefore be easier to spot, at least if there are many.
Detection combing
A comb with flat-faced teeth and a tooth spacing of 0.2-0.3mm is best. Detection combing can be carried out on dry or wet hair. Dry combing takes less time, but wet combing is more accurate because washing with conditioner stops head lice moving.
HEAD LICE SHOULD NOT CAUSE EMBARRASSMENT
They don't discriminate based on income, race, hygiene or pretty much any other factor. If you have a head of hair with a scalp underneath it, that warm, moist environment, clean or dirty, is just what they're looking for.
Suffocate the Lice
Soak your child's head in olive oil or coconut oil. Cover with a shower cap for at least 2 hours (or preferably overnight). When ready, remove the shower cap, and separate the hair into small sections, then use a metal nit comb to carefully remove the lice and eggs. Rinse the hair well with shampoo.