A disease of the connective tissue, caused by an infection with the gram-positive bacteria Streptococcus pyogenes (the disease may also affect the heart, joints, central nervous system, subcutaneous tissues, or skin). This disease is characterised by fever, polyarthritis, carditis, subcutaneous nodules, or erythema marginatum. Transmission is through haematogenous spread to other parts of the body after direct or indirect contact. Confirmation is by electrocardiography, sedimentation rate, or identification of Streptococcus pyogenes in a blood sample.