Why does invasive group A streptococcal disease occur?
Invasive group A streptococcal infections occur when the bacteria get past the defenses of the person who is infected. This may occur when a person has sores or other breaks in the skin that allow the bacteria to get into the tissue. Underlying health conditions that decrease a person’s immunity to infection also make invasive forms of the disease more likely. In addition, certain strains of group A streptococci are more likely to cause severe disease than others.
