2G8 BACTERIA PATHOGENIC TO MAN 



days after birth, showed evidences of general typhoid infection icterus 

 and rose spots. 



Not infrequently typhoid bacilli are found in the secretions. They 

 are present in the urine in about 20 per cent, of the cases in the third 

 and fourth weeks of typhoid fever. Slight pathological lesions in the 

 kidneys almost always occur in typhoid fever, but severe lesions also 

 sometimes occur. In some cases the urine is crowded with typhoid 

 bacilli. 



In cases of pneumonia due to the typhoid bacillus it is abundantly 

 present in the sputa, and care should be taken to disinfect the expec- 

 toration of typhoid patients. In typhoid fever the bacilli are almost 

 always present in the gall-bladder. The bacilli are usually eliminated 

 by the feces, being derived from the ulcerated portions of the intestines ; 

 their growth within the intestinal contents is, with few exceptions, not 

 extensive. 



Not only do the very great majority of cases examined bacteriologically 

 and pathologically, but the epidemiological history of the disease, proves 

 that the chief mode of invasion of the typhoid bacillus is by way of 

 the mouth and stomach. The infective material is discharged principally 

 by means of the excretions and secretions of the sick namely, by the 

 feces, the urine, and occasionally by the sputum. 



Occurrence in Healthy Persons. In a few cases they have been 

 obtained from the intestines of healthy persons. (Drigalski and Conradi,. 

 Zeit. Hyg., vol. xxxix. p. 283.) 



Duration of Life in Man. The bacilli usually disappear from the 

 body in the fourth or fifth week, but may remain for months or excep- 

 tionally years in the urine and in the gall-bladder. They have been 

 found in collections of pus one year after recovery from typhoid fever. 



Duration of Life Outside of the Body. It is of importance to know 

 for what length of time the typhoid bacillus is capable of living outside 

 of the body; but, unfortunately, owing to the great difficulties in proving 

 the presence of this organism in natural conditions, our knowledge on 

 this point is still incomplete. In feces the length of life of the typhoid 

 bacilli is very variable, depending on the composition of the feces and 

 of the varieties of bacteria present; sometimes they live but a few hours, 

 usually a day, exceptionally for very long periods. Thus, according to 

 I>evy and Kayser, in winter typhoid bacilli may remain alive in feces 

 for five months. Foote says that they can be found in living oysters 

 for a month at a time, but in numerous experiments we have not been 

 able to find them after five days. Their life in privies and in water, 

 however, is usually very much shorter. As a rule, they can be detected 

 in river water no longer than seven days after introduction, and often 

 not after forty-eight hours. The less contaminated the water, the longer 

 the bacilli are apt to live. The life of the typhoid bacillus varies accord- 

 ing to the abundance and varieties of the bacteria associated with it, 

 and according to the presence or absence of such injurious influences 

 as deleterious chemicals, high temperature, light, desiccation, etc., to 

 which it is peculiarly sensitive. Good observers claim to have found 



