134 BACTERIOLOGY FOR NURSES 



matous gangrene; the Bacillus botulinus, found in 

 raw meat and the cause of many cases of meat 

 poisoning; and the Bacillus fusiformis, iouad in an 

 affection of the membranes of the mouth and 

 throat. 



INFLUENZA 



Influenza (commonly known as La Grippe or 

 Grippe) is an infectious catarrhal disease of the 

 respiratory tract caused by Bacillus influenzal, the 

 constitutional symptoms being due to the toxins 

 produced by the bacilli growing in the mucous 

 membranes, especially in the bronchii. 



The influenza bacillus is one of the smallest known 



pathogenic organisms, usually about 1.5 /a in length 



and 0.3 ju, in thickness; the ends of the rods are 



rounded, it is strictly aerobic, non-motile, and does 



-N not form spores. It stains with 



^\'V^^ \\\ ordinary dyes and is decolorized 



\^>y;N^Vi'.' ( by the Gram method. It grows 



^^'s'lT '''! best at body temperature, 37° C. 



'''/I (98.6° F.), but develops only upon 



Fig. 22.— Bacillus media to which blood has been 



infiuenzsR. 



added. Being an aerobic, its 

 growth takes place only upon the surface of the 

 medium employed. The colonies develop as minute 



