The relative importance of rheumatic fever as a cause of death has been stressed in recent years. It has been estimated that for each death of a person under 20 years of age due to the combined causes of pertussis, diphtheria and poliomyelitis there were 50 deaths due to rheumatic disease of the heart.1The United States vital statistics reports for 1944 list deaths from rheumatic fever as 0.1 per 100,000 population and the death rate for rheumatic disease of the heart as 20.4 per 100,000 population, in comparison with the crude death rate of 1,040 per 100,000 for all causes. The Metropolitan Life Insurance Company reported deaths in school children due to rheumatic fever, including rheumatic disease of the heart, as 5 to 6 per 100,000 among industrial policy holders.2These mortality statistics emphasize the public health aspects of rheumatic fever, but have limited prognostic value. Of