There are many different species of Streptococcus bacteria. Most of them are harmless to humans and some are actually part of the large group of microbes found naturally in our body.
When the streptococcus bacteria gain access to tissue in the body like the blood, blood, muscle, or the lungs they can cause a lot of damage. To eliminate the bacteria in this case the usual treatment is a course of anti-biotic.
Streptococcus bacteria are spread from those that are infected by the bacteria to others when they come in direct contact with mucus from the nose and throat of patient. This happens when the person coughs or sneezes. The bacteria are also spread if others touch the wounds, of patients suffering from ailments where the bacteria enter the muscles, without any protection. The bacteria are not spread by contact with items used by the infected person or with water, food, etc.