The first thing to understand is that head lice actually prefer clean hair, so having head lice does not mean you are "dirty". Lice look like little insects without wings. They lay their eggs call nits near the base of the hair close to the scalp. The nits look like little grains of sand. They are stuck on the hair shaft.
They cause itchiness and can be spread by close contact. It is important to check your children for head lice regularly. They must be treated properly to prevent lice spreading to others. You only need to use a head lice treatment if you actually have head lice. Using head lice preparations if there are no lice does not prevent head lice. It can irritate the scalp and cause resistance to that preparation.
Ask your Pharmacist which is the best head lice treatment for you. There are many products available including some natural ones which are also very effective. Remember to always use the product as per the instructions. In many cases, a second treatment is needed after 7 days.
Once a product is used, the nits will still be present and need to be removed with a fine tooth comb. To make it easier to remove the nits, you can put olive oil through the hair or spray a mixture of vinegar and water onto the hair. Then use the fine tooth comb to remove. Using tea-tree oil mixed with water and sprayed onto the hair daily can sometimes prevent head lice.
Some people also spray a small amount of hairspray onto the hair each day which makes it harder for the lice to attach themselves to the hair shaft. Note that even after treatment, the head can still be itchy for up to a week. So if there are no lice or nits present, there is no need to worry.
Remember to inform the school and parents of any other children your child has been playing with so they can check their hair also.