Rheumatic fever results from an infection caused by certain strains of streptococcal bacteria and may be triggered by a strep infection (most often strep throat) that has not been treated. Proper treatment of strep infection can prevent rheumatic fever.

Rheumatic fever affects the joints and heart, causing symptoms similar to arthritis as well as heart problems (rheumatic heart disease). Rheumatic fever may also affect the skin, brain, and other organs and tissues. Most of the damage caused by rheumatic fever is temporary. But if any heart damage develops, it is usually permanent.