While scarlet fever has been widespread for centuries, it has long been confused with other diseases and was only clearly identified at the end of the 19th century. During the years that followed, it was studied more closely, making it possible to develop serums and vaccines. Today, the disease is much more rare. Nevertheless, every winter it still continues to plague children ages 5 to 10.This gives rise to small epidemics that spread among children at school, typically during the colder months. It's rare that it affects children under the age of 2 years old. It is estimated that by 10 years old, 80% of children have already been exposed to the agent responsible for scarlet fever. They will be protected for the rest of their lives, except in rare cases. As such, the disease is very rarely found in adults. What is Scarlet Fever?Scarlet fever is an infectious disease caused by the bacterium Streptococcus pyogenes (group A streptococcus). Once in the body, it secretes toxins that can be of several types: A, B, C, and D. They will cause the appearance of signs of scarlet fever. However, type A toxins will lead to a more virulent form of the disease than type B or C toxins. All four types cause the appearance of "raspberry red" coloration of the skin. The main signs are cutaneous, but scarlet fever is also associated with other symptoms.