It is uncommon in the U.S. except in people who have had untreated strep infections. It may occur in adults or children but is most common in children 5 to 15 years old.
Rheumatic fever is associated with the development of valve disease and other heart disorders.
There are also a grouping of minor criteria. Two major criteria, or one major and two minor criteria, are suggestive of rheumatic fever. Prompt treatment of strep. An echocardiogram will show myocarditis. A chest X-ray may also be recommended.