TYPHOID BACILLUS 337 



of typhoid fever in a considerable number of cases. Thus, Neufeld 1 

 obtained cultures in 13 of 14 cases examined, and Richardson obtained 

 them in 5 out of 6 cases. Both Neufeld and Richardson emphasize 

 the importance of incising several spots. The technic developsd by 

 Richardson is as follows: the skin over several rose spots is cleaned 

 as for a surgical operation and then frozen by a spray of ethyl chloride. 

 This procedure drives out most of the blood, as well as making the 

 operation practically painless. A small incision is then made with 

 a sterile knife and the substance of the rose spot is removed with a 

 small skin curette and at once placed in 0.1 per cent, dextrose broth, 

 and incubated for eighteen to twenty-four hours. The identification 

 of the bacilli which develop in the broth is made by the usual cultural 

 and agglutination reactions. 



2. Isolation of Typhoid Bacilli from the Urine. Typhoid bacilli 

 have been found in the urine in from 25 to 35 per cent, of the cases 

 examined. Such urines frequently contain albumin. The organisms 

 do not as a rule appear until the third week of the disease, conse- 

 quently their isolation is of comparatively little value diagnostically, 

 although their recognition is of great importance for the prevention 

 of secondary cases. The organisms may exist in the urine for a few 

 weeks after recovery. Rarely they persist for months or very rarely 

 for years after recovery. Frequently their presence is not mani- 

 fested by clinical symptoms, but occasionally persistent cystitis may 

 be caused by their continued growth in the urinary bladder. Usually 

 the bacilli present in the urine are found in pure culture. Occasionally 

 colon bacilli are found either in association with typhoid bacilli or 

 even in pure culture after the typhoid bacilli have disappeared. 



3. Isolation of Typhoid Bacilli from Feces. Typhoid bacilli are 

 usually found in pure culture or nearly pure culture in the blood, and, 

 if the proper precautions are observed, in the urine as well. In the 

 feces, on the contrary, they are usually in the minority and their 

 isolation presents certain difficulties. It has been claimed by many 

 authorities that typhoid bacilli are not found in the feces in demon- 

 strable numbers, at least until about the middle of the second week. 

 Klinger 2 has collected statistics from 812 contact cases which indicate 

 the danger of infection from feces even before the development of 

 clinical symptoms. 



1 Loc. cit. 



2 Public Health Reports, 1911, xxvi, 319. 



22 



