72 BACTERIOLOGY FOR NURSES 



not always due to an invasion of pneumococci, 

 neither does the pneumococcus always produce the 

 same results, the variations no doubt being largely 

 due to the condition of the individuals. It was 

 formerly thought that exposure to cold was the sole 

 cause of pneumonia, and it is true that such exposure 

 by lowering resistance opens the way for an invasion 

 of bacteria, while other factors, such as dissipation, 

 loss of sleep, lack of food, and prostration due to other 

 diseases, as typhoid fever, scarlet fever, and measles, 

 may all be contributory to an attack of pneumonia. 



There are three types of pneumonia : lobar (acute 

 croupous), 'broncho-pneumonia, or lobular pneumonia, 

 and capillary bronchitis. 



Lobar pneumonia is said to be due almost entirely 

 to the pneumococcus, which is found in the blood, 

 while lobular pneumonia and capillary bronchitis 

 are sometimes due to other organisms, as staphylo- 

 coccus, or streptococcus, or B. diphtheria, or B. 

 influenzce, or B. typhosus. Pneumococci are not only 

 the cause of lobar and lobular pneumonia, but 

 many other inflammations and suppurative condi- 

 tions, as inflammation of the middle ear, of the 

 meninges (meningitis), of the pleura (pleurisy), and, 

 in fact, infections due to the pneumococcus have 

 been found in nearly every organ of the body. 



