Читать книгу Epidemic Respiratory Disease. The pneumonias and other infections of the repiratory tract accompanying influenza and measles онлайн

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In consideration of the figures presented in Table IX it is important to remember that the group of 50 men from Hot Springs were all from isolated farm communities, had not previously been assembled and had not been in continuous contact with a widespread epidemic of influenza. On the other hand, the two groups of normal men at Camp Pike were studied immediately after the epidemic had swept through the camp and had been constantly in contact with epidemic influenza for a period of three months, 24 of the 51 actually having had the disease during this period. The fact that in the group of men from Hot Springs, B. influenzæ was found only by the mouse inoculation method is noteworthy, since it indicates that the organism was present in relatively small numbers and could be detected only by a highly selective method.

Table IXIncidence of B. Influenzæ in Normal Men Contrasted With That in Early Cases of Influenza as Determined by Multiple Cultures from Nose, Throat, and SputumDATEPLACEGROUPNUMBER EXAMINEDPER CENT SHOWING B. INFLUENZÆNOSETHROATSPUTUM DIRECT CULTURESPUTUM MOUSE INOCULATIONBY MULTIPLE CULTURESNov. 12Hot Springs, Ark.Normal draft men assembled to entrain for camp502222(4 cultures only)(31 cultures only)Nov. 25Camp PikeNormal men; 12 had influenza during the epidemic2638.65034.65080.8Dec. 10Camp PikeNormal men; 12 had influenza during the epidemic254852246888Oct. 10 and Nov. 19Camp PikePatients with influenza in Base Hos.2821.45060.778.6100

Summary of the results obtained in normal men shows that the incidence of B. influenzæ in normal individuals from isolated communities or in groups free from respiratory diseases prior to the occurrence of the fall epidemic was relatively low, namely, 10 to 20 per cent; that in observations made before the fall epidemic in groups in which “bronchitis” and pneumonia were fairly prevalent, B. influenzæ was found much more frequently, namely, in 25 to 50 per cent of the cases; and that in groups studied at intervals during the epidemic the incidence of B. influenzæ rapidly rose, reaching 85 per cent at the end of the epidemic. In contrast with this, B. influenzæ was found in 100 per cent of cases of influenza without reference to the time at which they occurred during the epidemic. It is obvious that the high percentage of normal men carrying B. influenzæ found at the end of the epidemic can depend only on the wide dissemination of B. influenzæ that must occur during epidemic times.