Lice

Head lice (Pediculus capitis) affect only humans, and cannot be passed on to, or caught from, animals. Infestation with head lice is also known as pediculosis.

Head lice are tiny (pin-head sized) grey-brown, wingless insects that live by sucking blood from the scalp. Their eggs, which look like tiny white specks, are known as nits and are laid glued to the base of hairs.

The eggs hatch after seven to 10 days, and 10 to 14 days after hatching the lice are mature and 2-4mm long (the size of a sesame seed). Once mature they start to reproduce, so numbers can grow alarmingly if not treated.

Head lice are common in schoolchildren, particularly between the ages of four and 11, but anyone with hair can catch them.

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