Chagas' disease; a clinical, epidemiologic, and pathologic study.

C ONSIDERABLE advances in the clinical aspects of Chagas' disease have been made in the last decade. In the historical review of our knowledge 3 periods may be recognized.'5 1. The first period began with the clinical descriptions made by Chagas.2' 3 He described an acute form4 and several chronic forms3' 5 of American trypanosomiasis. He was greatly impressed6' 7 by the cardiac disturbances exhibited by many persons from the region in which the disease was discovered and claimed that such cardiac disturbances were related to chronic American trypanosomiasis. 2. From 1913 to 1943 acute cases of Chagas' disease were described in 15 American countries. Various authorities doubted an etiologic relationship between Schizotrypanum cruzi (Trypanosoma cruzi) infection and the chronic forms described by Chagas; only a few cases of chronic Chagas' disease were reported up to 1945. The concept of Chagas' disease as an uncommon acute disease was generally accepted. The true medical and social importance of this endemic infection was not appreciated. 3. Carlos Chagas' original observations on the cardiac disturbances in chronic S. cruzi infection have been confirmed and considerably extended'0-'5 in the last 10 years. Epidemiologic studies, observations of the clinical manifestations, the description of the electrocardiographic changes, improved laboratory diagnosis, the pathologic studies, and, finally, the production of a chronic type of heart