Lice are the most common of human parasites. Parasites feed of another animals. Head lice are six legged wingless parasitic insects with claws. They can grow to the size of a match head so can be seen with the naked eye. They feed by drawing blood when they bite the scalp.
INFESTATION
Clean hair offers no protection against head lice. Head lice infestation affects people of all ages and backgrounds. A female's average life span is about a month. A female can lay up to 8 eggs a night. The eggs are individually glued on to the base of the hair shaft. As hair grows on average 1cm per month, the position of the egg on the hair shaft from the base of the scalp indicates the length of time they have been present. The eggs are creamy-brown in colour.
After 7-10 days the lice will emerge from the egg leaving behind the empty white case known as a nit. After 7 days the lice has reached sexual maturity and can reproduce. They can be found all over the hair but are more easily detected in the hair behind the ears and at the base of the neck.
Head lice can be passed between family members, close friends & in situations of close head contact. As the lice cannot fly they pass when heads are in close contact. Children aged 4-9 are most affected because of close contact through playing.
SYMPTOMS OF INFESTATION
Symptoms of itching only occur in 36% of affected people. Itching is caused by an immune reaction to the lice feeding on the scalp.
The most reliable method is frequent combing to see if a louse can be detected. Finding live lice means there is infestation. Once a case has been identified those in contact with that person must be checked.