300 BACTERIA AND DISEASE 



by persons not suffering from the disease. It is believed that the 

 virus of typhoid fever is chiefly distributed by the contents of the 

 alimentary canal, and this view is so universally held that it is 

 unnecessary to elaborate it. 



The urine is the other chief excretion by which the bacilli of 

 typhoid fever are voided from the body. Horton-Smith has demon- 

 strated that the urine of typhoid patients contains the bacilli of the 

 disease in the proportion of one in every four cases. He has also 

 shown, that, as a rule, it is towards the end of the disease, or during 

 convalescence, that this condition occurs. Further, whilst it is 

 always diflicult to find the bacilli in the stools, in the urine it is 

 generally easy, for when they are present they are nearly always in 

 pure culture, and not uncommonly they are present in such extra- 

 ordinary numbers that one cubic centimetre may contain many 

 thousands of micro-organisms (Horton-Smith). Cammidge found 37 

 per cent, of all the typhoid urines examined contained the bacillus. 

 In one case the organism was found eight months after convalescence. 

 In London, Horton-Smith found typhoid bacilli present in the 

 urine in 25 per cent, of all cases examined. Working in Boston, 

 Eichardson obtained a positive result in 22"5 per cent, of the 

 cases examined. Both the last-named investigators found the 

 bacilli present, in certain cases, in such large numbers that the 

 urine was rendered turbid by their presence. Nor are such 

 cases rare. Out of the cases in which the specific bacillus was 

 present in the urine, in as many as twelve it was present to the 

 degree of turbidity, and in only two was the urine described as 

 " clear " (Horton-Smith). Eef erring to the stage of the disease in 

 which the bacilli appear in the urine, they have been found as early 

 as the thirteenth day from the commencement, and as late as the 

 fourteenth day of convalescence (Horton-Smith). Speaking gener- 

 ally, the condition is rare before the third week of the disease. The 

 duration of this specific bacilluria also varies. The shortest duration 

 recorded by Horton-Smith was eight days, but in four other cases it 

 had not disappeared until after the lapse of twenty-one days, twenty- 

 five days, thirty days, and seventy days. The phenomenon of typhoid 

 bacilli in the urine probably occurs because one or more bacilli find 

 their way into the bladder, and there commence rapid growth in the 

 urine within the bladder, which medium is by no means unfavour- 

 able to the multiplication of the bacillus (Horton-Smith). 



From these facts there are two broad deductions which concern 

 the bacteriologist and epidemiologist: — First, that enteric fever 

 occurs as a result of infection by the typhoid bacillus ; and secondly, 

 that the typhoid bacillus leaves the body of the infected person 

 through two chief channels, namely, the urinary and alimentary 

 systems. It has been shown further, that the typhoid bacillus is 



