79 



organism; 31 yielded a moderate number of colonies, while 

 from 20 only one or two colonies could be identified. Of the 

 28 positive specimens from catarrhal and influenzal pneumonia 17, 

 including 6 of those from the lung post mortem, furnished an 

 abundant crop of typical colonies ; 7 yielded a moderate number 

 and 4 a few only. Of the 9 specimens from cases of simple 

 bronchitis eight yielded influenza bacilli, five of them in 

 abundance. 



Table 2. 



Isolation of Influenza Bacilli from the Normal Nasopharynx. 



Population. 



Date. 



Total. 



Positive. 



Per- 

 centage 

 Positive. 



Out-patients at St. Bartholomew's 

 Hospital - 



Out-patients at Lambeth Infirmary 



Healthy school children in West- 

 minster - 



37 



42 

 32 



70 

 36 



The figures preceding the last set represent individual out- 

 patients, not suffering from respiratory disorder, from whose 

 nasopharynx influenza bacilli were isolated from the only swab 

 taken. It will be observed that during the periods of these 

 examinations the influenza bacillus was quite a common 

 inhabitant of the mucous membrane of the normal upper air- 

 passages. In the case of the last group, the healthy school 

 children, the swabs were taken from the nose and not from the 

 nasopharynx and had already been used to inoculate Loffler's 

 medium in the search for diphtheria carriers. The majority of 

 the positive swabs, both from the children and the out-patients, 

 gave cultures in which influenza bacilli were only moderate in 

 number : swabs yielding abundant colonies were rare, as con- 

 trasted with cultures from sputum in disease. 



Table 3. 

 Isolation of Influenza Bacilli from Cases of Influenza. 



