Toxic Products 549 



that epidemics of typhoid fever had never been traced to 

 polluted ice, Sedgwick and Winslow * made some investiga- 

 tions to determine what quantitative reduction might be 

 brought about by freezing, and accordingly experimentally 

 froze a large number of samples of water intentionally in- 

 fected with large numbers of typhoid bacilli from different 

 sources. It was found that the typhoid bacilli disappeared 

 in proportion to the length of time the water was frozen, 

 and that the reduction averaged 99 per cent, in two weeks. 

 The last two or three germs per thousand appeared very 

 resistant and sometimes remained alive after twelve weeks. 



They have been found to remain alive upon linen from 

 sixty to seventy-two days, and upon buckskin from eighty 

 to eighty-five days. Sternberg has succeeded in keeping 

 hermetically sealed bouillon cultures alive for more than a 

 year. In the presence of chemic agents the bacillus is also 

 able to retain its vitality, from o. i to 0.2 per cent, of carbolic 

 acid added to the culture media being without effect upon 

 its growth. At one time the tolerance to carbolic acid was 

 thought to be characteristic, but it is now known to be 

 shared by other bacteria (colon bacillus). The bacilli are 

 killed in a short time by thorough drying. 



Metabolic Products. The typhoid bacillus does not 

 produce indol. It produces a small amount of acid, as is 

 shown by reddening of litmus milk. It forms no coagulat- 

 ing or proteolytic enzymes. 



Toxic Products. The disproportion of local to consti- 

 tutional disturbance in typhoid fever and the irritative 

 and necrotic character of its lesions suggest that we have 

 to do with a toxic bacterium. Brieger and Frankel have 

 indeed separated a toxalbumin which they thought to be 

 the specific poison from bouillon cultures. When injected 

 into guinea-pigs the typhotoxin of Brieger causes salivation, 

 accelerated respiration, diarrhea, and mydriasis, and usually 

 leads to a fatal termination in from twenty-four to forty- 

 eight hours. Klemperer and Levy also point out, as afford- 

 ing clinical proof of the presence of toxin, the occasional fatal 

 cases in which the typical picture of typhoid has been with- 

 out the characteristic postmortem lesions, the diagnosis 

 being made by the discovery of the bacilli in the spleen. 



* "Jour. Boston Soc. of Med. Sci.," vol. iv, No. 7, p. 181, March 

 20, 1900. 



