Our grateful acknowledgment is due the Staff of the New Haven Hospital, especially the members of the Department of Medicine, for their hearty co-operation and for the use of the clinical notes. We also wish to thank the members of the Medical Corps of the United States Army who were stationed at the Yale Army Laboratory School while the work was in progress and who aided in many ways:—Colonel Charles F. Craig, Captain R. A. Lambert, Lieutenants C. A. McKinlay, Frederick Parker, Jr., Ellis Kellert, Henry R. Muller, and J. H. Globus.
TABLE OF CONTENTS
| Page | |||||
|---|---|---|---|---|---|
| Introduction | [9] | ||||
| I. | The Pathology of the Respiratory Tract in Influenza | [13] | |||
| (A) Lesions of the Trachea and Bronchi | [13] | ||||
| (a) Gross Picture | [13] | ||||
| (b) Histological Picture | [14] | ||||
| (c) Summary | [16] | ||||
| (B) Lesions of the Lung | [16] | ||||
| (1) Acute Diffuse Fulminating Type | [18] | ||||
| (a) Gross Picture | [18] | ||||
| (b) Summary | [19] | ||||
| (c) Histological Picture | [20] | ||||
| (d) Summary | [22] | ||||
| (2) Localization and Necrotization of the Pneumonic Process | [22] | ||||
| (a) Gross Picture | [22] | ||||
| (b) Histological Picture | [24] | ||||
| (c) Summary | [26] | ||||
| (3) Organization of the Bronchiolar and Pneumonic Processes | [26] | ||||
| (a) Illustrative Protocols | [27] | ||||
| (b) Summary | [30] | ||||
| II. | Influence of the Respiratory Complications of Influenza upon Tuberculosis of the Lung | [32] | |||
| (a) Illustrative Protocols | [32] | ||||
| (b) Summary | [33] | ||||
| III. | Extrarespiratory Lesions in Influenza | [34] | |||
| (A) Lesions of the Hematopoietic System | [34] | ||||
| (a) Lymphadenoid Tissue | [34] | ||||
| (b) Spleen | [35] | ||||
| (c) Bone Marrow | [35] | ||||
| (B) Lesions of the Blood Vessels and Elsewhere in the Body | [36] | ||||
| (a) Vascular System | [36] | ||||
| (b) Skeletal System | [36] | ||||
| (c) Parenchymatous Organs | [36] | ||||
| (d) Alimentary Canal | [37] | ||||
| (e) Urinary Bladder | [37] | ||||
| (C) Miscellaneous Lesions | [38] | ||||
| (a) Parenchymatous Organs | [38] | ||||
| (b) Jaundice | [39] | ||||
| (c) Central Nervous System | [39] | ||||
| (d) The Pregnant Uterus | [39] | ||||
| (e) Summary | [39] | ||||
| IV. | A Comparison between the Respiratory Lesions of Influenza and those Initiated by the Inhalation of Poisonous Gases with Special Reference to:— | [40] | |||
| (A) The Inflammatory Response versus the Systemic Capacity to Compensate | [40] | ||||
| (B) The Primary Injury | [41] | ||||
| (C) The Tendency to Organization of Bronchiolar and Alveolar Exudates with Bronchiolitis and Bronchiolectasis as Sequelæ | [42] | ||||
| (D) The Importance of the Trachea and its Ramifications as a Protective Mechanism against Infection of the Pulmonary Parenchyma | [42] | ||||
| V. | Peculiarities of the Histology of Influenzal Pneumonia | [44] | |||
| (A) The Extent of the Initial Pulmonary Lesion | [44] | ||||
| (B) The Hemorrhagic Exudate—The Relation of Red to Grey Hepatization | [44] | ||||
| (C) The Aplastic Exudate | [45] | ||||
| (D) The Hyaline Necrosis of the Pulmonary Tissue | [46] | ||||
| (E) The Organization Process | [46] | ||||
| VI. | Infection as a Possible Etiological Factor for Malignant New Growths | [48] | |||
| VII. | The Bacteriology of Influenzal Pneumonia | [49] | |||
| (A) Organisms Associated with Influenzal Pneumonia | [49] | ||||
| (B) The Relation of the Type of Organism to Pleural Involvement | [50] | ||||
| (C) The Relation of Different Organisms to the Type of Pneumonia | [50] | ||||
| (D) Summary and Discussion | [54] | ||||
| VIII. | Conclusions | [55] | |||
| IX. | Bibliography | [56] | |||
| X. | Illustrations | [63] | |||
FIG. II. AUTOPSY NO. 98. DRAWING OF A SECTION THROUGH A TRACHEA SHOWING NECROTIZING HEMORRHAGIC INFLAMMATORY PROCESS OF THE MUCOSA.
INTRODUCTION
The epidemic of influenza, prevalent in Europe during the Great War, was watched with interest everywhere, not only because of its military importance, but also because of the danger of its spreading to other continents. The prediction that this would occur, made months before its realization, was verified on an even larger scale than had been anticipated, for in the autumn of 1918, this acute respiratory infection passed over the United States like a huge wave, taking a tremendous toll in human lives; later smaller waves followed leaving in their wake corresponding degrees of devastation. The first cases of the disease appeared on the New England coast, and New Haven was among the cities to be early invaded, though here the epidemic was somewhat less severe than in other cities along the Atlantic Seaboard.
Forewarned and alert to the danger, medical men spared no effort in studying the disease; as a result, no malady, perhaps, has ever been investigated so intensively and from so many different points of attack in an equal length of time. Proof of this appears in the abundant literature issuing from every quarter. Among the various contributions to this subject, many include the anatomical changes associated with the disease. In general, however, these are brief; and although they serve their special purpose well, they have not been elaborated sufficiently to close the chapter.
During a period of about three months beginning with September 18, 1918, while the epidemic raged and waned in New Haven, there were approximately eleven hundred cases of the disease admitted to the New Haven Hospital. As is so often true, only the more critically ill sought hospital care, and few, if any, patients affected by other respiratory infections are included in these statistics. The mortality here, as elsewhere, was very high; of two hundred eighty (280) cases that ended fatally, eighty-two (82) were investigated at the post-mortem table. An attempt was made to make the studies very complete, and this was favored since the headquarters of the Yale Army Laboratory School, under the command of Colonel Charles F. Craig, were located at the Brady Laboratory where a large number of men were being instructed in Pathology and Bacteriology. It was also fortunate that competent illustrators were available who made a splendid series of water-colors and drawings of the characteristic lesions, both gross and microscopic.