216 ^^^6 Philippine Journal of Science wn 



cholera vibrios are not found as regularly as they are in the 

 proximal part of the intestine. They are rarely excreted in the 

 faeces, unless the sojourn of the intestinal contents is hastened 

 through the large intestine and the conditions are made favorable 

 to the survival of the cholera vibrios. (4, 5) 



From these findings it is evident at once that the problem of 

 drug treatment in experimental cholera carriers is one of great 

 difficulty. Even a drug which, given by mouth, would exert 

 bactericidal action upon the cholera vibrios in the intestine would 

 not bring about a complete and permanent disappearance of 

 cholera vibrios from the body organism unless it was eliminated 

 through the bile in such a chemical form as to be toxic to the 

 cholera vibrios in a higher degree than it is deleterious to the 

 body organism. 



Guinea pigs were selected for these experiments for several 

 reasons. It has been found and already mentioned in a previous 

 paper that the inflammation of the gall bladder, following the 

 intravesicular injection of cholera culture, is far more intense 

 in rabbits than in guinea pigs. (3) It was to be expected, there- 

 fore, that the effect of a drug would be evident in case of a 

 slight infection, more so than in a case of a severe one. Further- 

 more, in previous experiments on six rabbits, which were found 

 positive in from three to thirteen days after the infection, four 

 harbored the cholera vibrios in the gall bladder only (3) and not 

 in the intestine. Should rabbits be used for treatment experi- 

 ments, it would be difficult at times to say whether or not the 

 disappearance of cholera vibrios from the intestine, in itself a 

 therapeutic result of value, is due to the action of the drug. Be- 

 sides these considerations it was found technically more con- 

 venient and more economic to use guinea pigs. 



THE ARRANGEMENT OF EXPERIMENTS 



Infection. — The intravesicular injection was used exclusively 

 in these experiments. A recently isolated culture of cholera was 

 grown in ox bile and transplanted in agar twenty-four hour? 

 before the injection was performed. The animals were shaved, 

 and the skin was washed with lysol solution and then painted 

 with tincture of iodine. In performing the operation, an incision 

 was made from the middle of the xiphoid process to the right 

 costal margin. As soon as the muscles were separated, the peri- 

 toneum became visible and through it the xiphoid process. The 

 latter was clasped with a hemostat and lifted up, whereupon the 

 duplicature of the peritoneum formed thereby was perforated 

 by means of a dull forceps. As a rule, the gall bladder was 



