644 MICROBIOLOGY OF THE DISEASES OF MAN AND ANIMALS. 



The organism enters the body through the mouth by means of infected 

 fingers, food, milk, and water, etc. 



On reaching the intestine the organism probably propagates to some 

 extent before penetrating the intestinal mucosa. It enters into the blood 

 stream and is disseminated throughout the body. According to the 

 endotoxin theory it must slowly be dissolved by the lytic substances 

 which have been gradually accumulating in response to the primary 

 intoxication. 



The organisms have been cultivated from the rose spots and have been 

 found in vomit without the presence of blood, and in sputum. Typhoid 

 meningitis and osteitis occur occasionally. At autopsy the spleen and 

 gall bladder yield the highest number of positive cultures. It is of in- 

 terest to note too that while the highest percentage (89-90 per cent) of 

 positive blood cultures occurs in the first week and that the percentage 

 diminishes from then on, the number of positive findings in the faeces, 

 on the other hand, runs in the opposite direction. 



Generally speaking, one attack confers immunity. Upon what anti- 

 bodies immunity and recovery depend is a matter of controversy. 



The elimination of the bacilli from the body will largely depend upon 

 the stage of the disease, since the blood, especially early in the illness, prac- 

 tically always contains the specific organism; epistasis is not an unim- 

 portant feature as a possible means of disseminating the germs. The 

 bacilli can also escape in the fasces, urine, sputum, and vomit. 



In the control of this disease the best place to begin is at the bedside. 

 Disinfection of all excreta and of everything which comes in con- 

 tact with the patient should be rigorously carried out and in the case of 

 the fasces and urine should ideally be continued until examination can 

 be made showing absence of the organism. It has been estimated that 

 as high as 5 per cent of convalescents continue to excrete living typhoid 

 bacilli for varying periods from months to years after the disease; the 

 longest time noted has been forty-six years. 



The recognition of typhoid carriers will depend absolutely on the 

 finding of the specific germ in the feces or urine as the case may be. 

 Where there are large numbers of suspects, the opsonic index is claimed 

 to be an aid in exclusion of the improbable ones, as well as the agglutinin 

 reaction. 



In a general way, prompt recognition of the source of infection such 

 as milk, polluted water, bacilli-carriers, etc., together with instruction of 



