Head lice infestation is a condition caused by a parasitic insect. Live lice can be found anywhere on the scalp; the eggs are most commonly found behind the ears and at the back of the neck. The severity of infestation varies from a few lice to thousands of lice, but a typical infestation might have about 30 lice per head. Head lice infestation is most common in children 4–11 years of age.
Confirming active infestation of head lice includes systematic combing of wet or dry hair with a head lice detection comb. A live louse must be found in order to confirm active head lice infestation. An itching scalp is not sufficient to diagnose active infestation.
The presence of louse eggs alone, whether hatched (nits) or unhatched, does not indicate active infestation as it is hard to distinguish between dead and live eggs with the naked eye, and eggs may maintain a viable appearance for weeks after death.
All members of the household and close contacts should also be checked for head lice as untreated family members and close contacts may cause re infestation in the people, who have been treated.
Treat head lice as soon as you spot them. You should check everyone in the house and start treating anyone who has head lice on the same day. There's no need to keep your child off school if they have head lice.
Lice and nits can be removed by wet combing with a special fine-toothed comb (a detection comb). Do wet combing on days 1, 5, 9 and 13 to catch any newly hatched head lice. Check again that everyone's hair is free of lice on day 17.
A pharmacist may recommend using medicated lotions and sprays. These kill head lice in all types of hair, and head lice should die within a day. Some treatments need to be repeated after a week to kill any newly hatched lice. Check the pack to see if the lotion or spray is OK for you or your child and how to use them. Speak to your pharmacist if you need further advice on any medicated treatments.
If lotions or sprays do not work, speak to a pharmacist about other treatment options.
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