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BACTERIOLOGY. 
influenza, has so far baffled discovery. The influenza 
bacillus was isolated from the sputum in a large per¬ 
centage of cases, but other organisms were also, not¬ 
ably the Hemolytic streptococcus, the pneumococcus 
(all types), the Friedlander bacillus, and the Micro¬ 
coccus catarrhalis. It has been impossible for bac¬ 
teriologists throughout the world to reach any con¬ 
clusion as to which one of these organisms, if any, 
was the primary cause of the disease. 
The results of efforts to immunize against the 
infection by means of vaccines containing the various 
organisms known to be present in the sputum are not 
conclusive, some believing them to be of value, others 
not. 
The Bacillus of Whooping Cough. 
The bacillus causing whooping cough was first 
described by two French bacteriologists, Bordet and 
Gengou, in 1900. It is very small, oval, and Gram 
negative. It shows bipolar staining and resembles the 
bacillus of influenza in growing best on culture media 
in which there is blood or its coloring matter. 
The infection localizes itself in the throat, nose, 
and bronchial tubes and is spread by the secretions 
from these parts. It is transmitted from one child to 
another, chiefly by direct contact, less often through 
dwellings and schools that have been infected. 
One attack generally protects during life; so 
cases of reinfection are very rare. The toxins of the 
bacillus are within the bodies of the bacterial cells 
