Group A streptococcus is a type of bacteria that can live in the back of the throat or on the skin, especially in children. It can spread between people through close contact or coughing and sneezing. In most people, it either causes no illness or only mild throat or skin infections or scarlet fever. Children with scarlet fever have a sandpaper-like rash over their body, often with fever and sore throat and a “strawberry tongue” – where the tongue is red with a white covering.