Part 2

(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.