498 A MANUAL OF BACTERIOLOGY 



Although epidemic influenza may be due to the B. influenzce, 

 many febrile conditions attended with pulmonary catarrh and 

 frequently termed " influenza " are not due to this organism. In 

 the "influenza cold" many organisms may be present, e.g. M. 

 catarrhalis, B. coryzce, pneumococcus, B. influenzce, etc. In an 

 epidemic simulating influenza occurring in Essex in 1905, the 

 examination was negative as regards streptococci, B. diphtherice 

 and B. influenzce, but the M . catarrhalis was present in number in 

 most cases (twenty-two out of twenty-four). Two other Gram- 

 negative cocci were also isolated from three other cases (see table, 

 p. 302). 



So-called " influenza meningitis " may be due to organisms 

 resembling, but not identical with, the B. influenzce (see " Menin- 

 gitis," Chapter XX). 



The influenzas of animals are probably distinct from human 

 influenza, though some have assumed a relationship between the 

 two. 



Clinical Examination 



In cases of influenza, accompanied with bronchitis or pneu- 

 monia, the influenza bacillus may be met with in large numbers 

 in the sputum. It may also be met with in the secretion in 

 catarrhal conditions of the respiratory tract. Film preparations 

 may be stained with carbol-methylene blue. 



Fleming x has devised some simple and excellent media for the 

 growth of B. influenzce : 



(1) Add 0-25 c.c. sterile blood to 5 c.c. melted agar, and boil in 

 a water-bath for one minute. The medium may then be sloped 

 or poured into a plate. 



(2) Mix 1 volume of blood, 5 volumes of water, and 1 volume 

 of normal sulphuric acid, and boil. This may then be stored ; 

 there is no need to use sterile blood. For use, 1 volume of normal 

 caustic soda is added ; the mixture should now be faintly alkaline. 

 The fluid portion which separates from the precipitate is then 

 added to liquid agar in the proportion of 1 c.c. of fluid to 5 c.c. of 

 agar. 



(3) These media grow not only the B. influenzce, but also the 

 pneumococcus and streptococcus very well. If to them brilliant 



1 Lancet, 1919, vol. i, p. 138. 



