Epidemic Respiratory Disease
The Pneumonias and Other Infections of the Repiratory Tract Accompanying Influenza and Measles
9781465647450
281 pages
Library of Alexandria
Overview
The bacteriologic studies in cases of influenza described in this report fully support Pfeiffer’s claim that B. influenzæ is invariably present in the disease. It is particularly important to note that these results were obtained in early uncomplicated cases of influenza and are not dependent upon cultures made from cases complicated by pneumonia or obtained at autopsy. In view of this fact the tendency so apparent in much of the recent literature to relegate B. influenzæ to a place of secondary or minor importance in the disease seems hardly justifiable. It would seem that this tendency is largely dependent upon three factors: first, the failure of many to find B. influenzæ either during life or at autopsy in any considerable proportion of cases; second, the frequent failure to draw a clear distinction between influenza itself and the pneumonia to which it predisposes with a consequent overemphasis upon autopsy bacteriology where a considerable variety of secondary organisms have attracted particular attention; and third, an incorrect interpretation of the undoubtedly large number of B. influenzæ carriers found among normal individuals and those with other diseases during the period of the epidemic and to less extent in interepidemic times. Since the majority of workers who are thoroughly familiar with the technic of cultivating B. influenzæ have encountered little difficulty in finding it in a large majority of cases, it is felt that the considerable number of negative reports that have appeared can depend only upon the unfamiliarity of those who have failed to find it with the proper bacteriologic methods. This is quite apparent in many of the reports that have been published, and is not surprising in the face of the excessive demand for well-trained bacteriologists occasioned by the war. One important feature in the successful isolation of B. influenzæ from all cases that has been brought out in the course of the work here reported, is the necessity of making simultaneous cultures from all portions of the respiratory tract, since by no single culture method was it found possible to find the organism in all cases. It has been pointed out that one of the most characteristic local phenomena of the disease is the rapidly progressing attack upon the mucous membranes of the respiratory tract. It seems quite possible that B. influenzæ in predominant numbers at least may be found in many cases only at the crest of the wave, if we may speak of it as such. By way of analogy is the well-recognized fact that the successful isolation of streptococcus from cases of erysipelas often depends upon taking cultures from the margin of the advancing lesion. While definite proof is lacking for this opinion, it would seem to receive some support from the observation that B. influenzæ rapidly disappears from the throat with the onset of convalescence in a considerable proportion of cases. It is felt that these observations, establishing the predominance of B. influenzæ in the early acute stages of the disease, are of considerable significance, especially when exactly the reverse condition was found in studying the incidence of the organism in cases of measles. In consideration of the primary cause of influenza, attention has often been focused upon the many different bacteria found in autopsy cultures. The most prominent of these are the ill-defined diplostreptococci of the European writers, the various immunologic types of pneumococci, and S. hemolyticus. Other microorganisms less frequently found are staphylococci, M. catarrhalis, nonhemolytic streptococci, and B. mucosus capsulatus. It is not within the scope of this paper to discuss their relation to the various types of pneumonia found at autopsy, but their very multiplicity would seem sufficient prima facie evidence that they bear no etiologic relationship to influenza and must be regarded only as secondary invaders.
