Head lice have nothing to do with hygiene. Anyone can get head lice, although they are more common in children. Head lice are spread through head contact or through the sharing of personal belongings (scarf, cycling helmet, etc.). Young children tend to have closer contact. That is why the primary school is a typical place where head lice are more easily spread. At any time, most schools will have a few children with active living head lice. Head lice do not discriminate between short or long, or clean or dirty hair.