A feverish illness marked by painful arthritis and a tendency to cause heart damage, resulting in chronic valvular heart disease. Its exact cause is not fully understood, but it appears to be linked to streptococcal infections of the throat and possibly a genetic predisposition. This condition primarily affects children, with girls more frequently affected than boys, and recurrent episodes are common. The main concern with this disease is the heart-related complications; long-term joint damage is rare and may not even occur.