AVENUES OF INFECTION 35 



stagnant, as in stenosis of the pylorus, and in carcinoma, when HC1 

 is diminished, or absent, fermentative bacteria give rise to great 

 amount of gas, and lactic acid, to the great discomfort of the patient. 

 The normal acidity of the stomach is a great safe-guard against 

 infection with cholera. If tubercle bacilli are swallowed, and if 

 infection occurs, the lesion is not always localized to the alimentary 

 tract. Lesions of the lymph glands, peritoneum, bones, and 

 nervous tissues often follow the ingestion of these organisms. Dogs 

 fed on soup containing great numbers of tubercle bacilli, and then 

 killed three hours after, were found to have bacilli in the thoracic 

 duct. Chyle from the duct, injected into guinea pigs, caused 

 tuberculosis in them (Nicolas and Descos). Cholera and typhoid 

 organisms thrive in intestinal contents, elaborating poisons which 

 greatly depress the individual. 



The interior of the uterus, the bladder, urine, and deep urethra, 

 are generally sterile in health. With the exceptions noted where 

 germs are not usually found, all tissues, especially the inlets and 

 outlets of the body, may be said to have a normal bacterial flora. 



The placenta is an avenue of infection in several diseases: notably 

 small-pox, anthrax, glanders, typhoid fever, and sometimes tuber- 

 culosis pass through the placenta from mother to foetus. Strep- 

 tococci may pass through the placenta of a woman with ante-deliv- 

 ery sepsis and cause peritonitis in the child. Recurrent fever has 

 been transmitted from mother to foetus, and the specific spirillum 

 has been detected in the latter's blood. 



A case has been recorded in which a woman suffering from pneu- 

 monia gave birth to a child, which died thirty-six hours afterward, 

 and autopsy revealed a consolidation of the lower left lung, and 

 microscopic examination discovered pneumococci. A hydrophobic 

 cow was delivered of a calf that developed rabies three days after 

 birth. 



McFarland divides microbic infection in three heads: 



Phlogistic. Characterized by restricted growth and local irrita- 

 tion. 



