Infectious Diseases and Traditional Medical Ideas about Inheritance. II. Tuberculosis, Syphilis, and Rheumatic Fever as Models

Infections largely defined medical practice well into the 20th century.Tuberculosis, syphilis, and rheumatic fever, common diseases with chronic components, and a major part of medicine in the pre-antibiotic era, are used here to examine traditional relationships between infections and inheritance.Experience with these conditions supported doctrines of heredity, degeneration, diatheses, and polymorphism that also applied to inherited disorders, and emphasized variability that opposed the distinct unit traits of Mendelism.