PATHOGENIC BACTERIA. 379 



of the pneumonia,* which frequently comphcates typhoid 

 fever, and may appear in the sputum. In times of epidemic 

 of the disease they may be present in the stools of persons who 

 show no symptoms of typhoid fever. Nieterf found 13 

 such typhoid fever bacillus carriers in a certain German 

 insane asylum. 



Inoculation experiments in animals have not been very 

 satisfactory. With a few possible exceptions, anatomical 

 lesions resembling those of typhoid fever have not been pro- 

 duced by the inoculation of typhoid bacilli into animals. The 

 injection of cultures into animals may produce death, but it can 

 usually be shown to have resulted from the poisons contained 

 in the cultures. 



BesredkaJ obtained endotoxins from the bacilli of typhoid fever, plague and 

 dysentery by triturating with salt to an impalpable powder, adding water, drop 

 by drop, allowing to remain over night, and vpith the typhoid bacilli heating 

 at 60 to 62° C. for two hours, allowing to settle and decanting the liquid which 

 contains the endotoxin with the plague and dysentery bacilli the separation is 

 affected without heat by centrifugaUzing. 



Typhoid fever is rare during the first two years of life. It 

 frequently attacks young and robust men. The causes that 

 bring about susceptibility to infection are not known. 



The principal lesion in typhoid fever lies in the Peyer's 

 patches of the lower part of the small intestines; the mes- 

 enteric lymph-nodes and spleen also are swollen. The typhoid 

 bacillus may be demonstrated in sections of the walls of the 

 diseased portion of the intestines. Cases are recorded in 

 which no lesions were found in the intestines, but where the 

 typhoid bacilli were widely spread through the organs of the 

 body, and which therefore represented typhoid septicemia. 



Periostitis and osteomyelitis, which are not uncommon 

 sequelas of typhoid fever, may be caused by typhoid bacilli. 



*Robinson. Journ. Infect. Dis. Vol, II. 1905. p. 498. 

 fMunchner. - Med. Wochenschr. Aug. 13, 1907. LIV. No. 33. 

 tBiM. de I'Inst. Past. Vol. IV., No. 13. July 15, 1906. pp. 586-587. 



