BACILLI OF THE COLON-TYPHOID-DYSENTERY GROUP 669 



fever is a distinctly preventable disease, amenable perhaps not to com- 

 plete eradication on account of the difficulties of the carrier problem, 

 but certainly readily subject to material diminution, much of this 

 suffering and economic loss would seem unnecessary. 



Infection with typhoid fever always means that intestinal contents 

 of a case or a carrier have come into direct or indirect contact with 

 something ingested by the patient. Since this is true, we may best 

 begin the description of the circle of infection from man to man by 

 first considering the manner in which the organism leaves the body of 

 the patient and the carrier. 



In the patient the typhoid bacillus begins to accumulate in the intes- 

 tines during the later stages of the incubation time, and at this time will 

 begin to appear in the feces. The organisms increase in the intestines 

 from this time on, being distributed in very considerable numbers after 

 the second week, and decreasing only towards the end of the disease, 

 remaining present, however, throughout convalescence and sometimes, 

 as we shall see, for months or years thereafter. During the second and 

 third or later weeks, the organisms appear in the urine. It is generally 

 stated that about 30 per cent of typhoid cases will show the organisms 

 in the urine, but it seems likely that this is too low an estimate. Rau- 

 bitschek, by precipitating considerable quantities of urine with ferric 

 chlorate succeeded in finding the bacilli in 100 per cent of his cases in 

 the^ earlier stages of the disease, and it is not at all Unlikely that in slight 

 numbers, and perhaps intermittently, they may appear in the urine of 

 all typhoid cases. Other routes of distribution from the patient, such 

 as suppurations, sputum, etc., are occasionally mentioned, but may be 

 dismissed as of no practical sanitary importance. 



Since the recognized typhoid case is usually well guarded from a 

 sanitary point of view, the greater danger of typhoid infection lies in 

 the mild, atypical, unrecognized case and in the carrier. Atypical, 

 mild cases will probably become more and more frequent as typhoid 

 vaccination becomes a more generalized habit. Such a case may show 

 nothing more than a very slight febrile movement, with intestinal dis- 

 turbances and diarrhea. Unless typhoid fever is particularly looked 

 for and suspected, many of these cases may never be put upon typhoid 

 precautions and the resulting possibilities of spread are obvious. 



More important from the sanitary point of view, under the con- 

 ditions of modern community life, however, is the typhoid carrier. 



TYPHOID CARRIERS. The great importance of the typhoid carrier 

 in the spread of the disease has led to extensive studies of the problem 

 in many countries during the last ten years. We may mention par- 



