Head Lice (Pediculosis) The dreaded word when school starts each year: Head Lice. Lice feed on human blood that can cause severe local itching. It can take 2 – 3 weeks for a person to notice the intense itching. Lice are spread through head to head contact or objects such as, combs, brushes, hats and scarves. Indication of head lice is usually itching at the back of the head and around the ears. Parents of school-aged children should perform scalp examinations on a consistent