356 BACTERIA PATHOGENIC TO MAN 



so frequently afford a resting place for the micrococci, we have only 

 to assume the production of a suitable culture medium for these para- 

 sites in the body, brought about by an abnormal condition of the mucous 

 membranes from exposure to cold, or a reduction of the vital resisting 

 power of the tissue cells in any of the internal organs, caused by disease, 

 traumatism, excesses of various kinds, etc., to comprehend readily how 

 an individual may become infected with pneumococci, either primarily 

 affecting the lungs and secondarily other organs in the body, or pri- 

 marily attacking the middle ear, the pericardial sac, the pleura, the 

 serous cavities of the brain, etc. 



Presence in Inflammatory Processes Not Secondary to Pneumonia. It 

 is now known that the pneumococcus may infect and excite disease in 

 many tissues of the body independent of any preliminary localization 

 in the lung. As a rule, these processes are acute and usually run a 

 shorter and more favorable course than similar inflammations due to 

 the streptococci. 



The most frequent primary lesions excited by the pneumococcus 

 after lobar pneumonia, bronchopneumonia, and bronchitis are probably 

 meningitis, otitis media, endocarditis, pericarditis, rhinitis, tonsillitis, 

 conjunctivitis, and keratitis; septicaemia, arthritis, and osteomyelitis; 

 inflammations of the epididymis, testicles, and Fallopian tubes; peri- 

 tonitis, etc. 



Pneumococcic peritonitis is not so very infrequent. The exudate 

 is usually seropurulent. 



Conjunctivitis due to pneumococci frequently occurs in epidemic 

 form and is frequently associated with a rhinitis. 



From statistics collected by Netter the following percentages of 

 diseases were caused by the pneumccoccus : 



Pneumonia . . . . . . 65.9 per cent, in adults. 



Bronchopneumonia ..... 15.8 



Meningitis ....... 13.0 



Empyema . . . . . . .8.5 



Otitis media ...... 2.4 



Endocarditis . . . . . .1.2 



In 46 consecutive pneumococcus infections in children there were: 



Otitis media 29 cases. 



Bronchopneumonia . . . . . > . 12 " 



Meningitis 2 " 



Pneumonia . . . . . . . . 1 " 



Pleurisy . 1 " 



Pericarditis . . . . . . . . . 1 " 



The pneumococcus and streptococcus are the two most frequent 

 organisms found in otitis media. The cases due to the pneumococcus 

 are apt to run the shorter course, but have a tendency to spread to the 

 meninges and cause a meningitis. The pneumococci may also find 

 their way into the blood current. 



In bronchitis the pneumococcus is frequently met with alone or in 



