136 
PRINCIPLES OF BACTERIOLOGY 
coccus and its susceptibility to drying precludes its be¬ 
ing found at large in nature. Coughing, sneezing, the 
use of infected handkerchief, etc., is sufficient to in¬ 
fect. 
Patients should be isolated and quarantined, the nurse 
should change her outer clothing before mingling with 
other people, she should carefully disinfect her hands 
and hair and spray her nose with some silver prepara¬ 
tion (argyrol, 10 per cent) ; the same thing applies to 
the patient before he is discharged. 
VI. Mechanism of Infection and Immunity 
Bacteriolysin and agglutinin are produced: menin¬ 
gococcus produces endotoxin. 
VII. Bacteriologic Diagnosis 
The bacteriologic diagnosis is made on finding Gram¬ 
negative cocci, arranged in pairs, both within and with¬ 
out the pus cells, on the fact that the organisms grow 
only on meat infusion media, on the source of the organ¬ 
ism (the cerebrospinal fluid), and if necessary, on 
agglutination. 
VIII. Immune Treatment 
To Flexner, of the Rockefeller Institute for Medical 
Research of New York, belongs the credit of preparing 
the first successful antimeningitic serum (from the 
horse), which has reduced the mortality of this dreadful 
disease from 70 to 80 per cent to 15 to 20 per cent. 
IX. Summary of Important Characteristics 
A Gram-negative organism, occurring in pairs, grow¬ 
ing only on meat infusion media, no spores, no flagella, no 
