SPECIAL BACTERIOLOGY 
135 
IV. Destruction 
Sunlight and drying kills the meningococci within 
twenty-four hours; they are extremely sensitive to heat 
and cold and are most readily destroyed by highly di¬ 
luted solutions of the common disinfectants. 
V. Disease Production, Mode of Infection, Disinfec¬ 
tion and Prophylaxis 
Meningococcus causes meningitis; it is usually ac¬ 
cepted that meningococci first lodge in the nose, whence 
Fig. 25.—The meningococcus. Smear of cerebrospinal fluid, x 1000. (Hew¬ 
lett —Manual of Bacteriology.) 
they enter the skull either directly (through the so-called 
cribriform plate of the ethmoid bone) or indirectly 
through the lymph vessels. 
The disease is transmitted directly from one human 
being to the other, as the low resistance of the meningo- 
