The results of the location of the germs in the throat or in wounds
depend on whether the individual is susceptible or immune. One attack
of scarlet fever is followed by immunity which usually lasts through
life. A second attack is very rare. Many persons probably are immune
because they have sometime passed through very mild forms of the
disease which were not recognized as scarlet fever at all. If the germs
have secured a footing in a susceptible person they grow and produce
their poisons or toxines. These cause inflammation of the tonsils, and
other parts of the throat and as the toxines enter the blood and are
carried to all parts of the body they cause fever, an eruption of the
skin, and injury to various organs, especially the heart and kidneys.