how long can you have lice before you know?
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You may not notice any symptoms for up to six weeks the first time you get lice.
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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.
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Although lice and their nits are small, they are visible to the naked eye. Head lice can be white, brown, or dark gray.
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Ukus (head lice) are TINY wingless insects, about the size of a sesame seed. They live on the human scalp and feed off of human blood. Adults can live for about 30 days on a person's head. Female lice lay eggs called NITS, which they glue to the hair shafts until they hatch in 8-9 days.
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Body lice live in the seams and folds of clothing. They feed on human blood and lay their eggs and deposit waste matter on the skin and clothing. Lice die within 3 days at room temperature if they fall off a person into most areas of the environment. However, they can live in the seams of clothing for up to 1 month.
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A female louse lays 3-5 eggs a day. The eggs hatch in 7-10 days and it takes another 7-10 day for the louse to mature and lay their own eggs. Do pets get head lice? Head lice cannot be “caught” from pets and cannot survive on pets.
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Repeat the anti-lice shampoo in 9 days. Be sure to do this or the lice may come back. Two treatments are always needed. The second treatment will kill any new lice that have hatched from eggs.
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(The CDC backs this up--they point out that because lice can't live off the human head for more than two days max, "you do not need to spend a lot of time or money on housecleaning activities.") Speaking of... 2. There's no need to wash your child's bedding every day.
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This is how they got the nickname “crabs.” Pubic lice are tan to grayish-white in color. Females lay nits and are usually larger than males. To live, lice must feed on blood. If the louse falls off a person, it dies within 1–2 days.
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Head lice sometimes go away on their own because there are not enough insects to maintain the infestation, or they may persist for an indefinite period without treatment. With proper treatment, the infestation usually goes away within about two weeks.
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Lice can also be spread through the sharing of personal articles like hats, towels, brushes, helmets, hair ties, etc. There is also a possibility of spreading head lice via a pillow, headrest or similar items. Head lice do not jump or fly and generally cannot survive longer than 24 hours off the host.
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It's important to follow this advice. Some treatments only need to be applied to the affected area, but sometimes the whole body must be treated, taking care to avoid the eyes. The treatment usually needs to be repeated 7 days later to get rid of any lice that have hatched during that time.
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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. Nits located further than ¼ inch from the base of hair shaft may very well be already hatched, non-viable nits, or empty nits or casings.
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Do not use a combination shampoo/conditioner, or conditioner before using lice medicine. Do not re–wash the hair for 1–2 days after the lice medicine is removed.
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If you see a small, oval blob on a strand of hair, that's probably a nit. If these little eggs are yellow, tan, or brown, the lice haven't hatched yet. If the eggs are white or clear, the lice have hatched.
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An infestation by body lice is typically diagnosed by looking at the skin and clothing and observing eggs and crawling lice. The insects are about the size of a sesame seed. They are big enough to see with the naked eye, but a magnifying lens can be used to help find them.
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Once the eggs hatch, lice are known as nymphs, an immature form of the parasite that is grayish tan in color. After nine to 12 days the nymphs mature into adults, the average size of which is roughly 2–3 millimeters, or about the size of a sesame seed.