﻿THE VITALITY OF THE CHOLERA VIBRIO IN MANILA WATERS 



By Otto Schobl 

 (From the Biological Laboratory, Bureau of Science, Manila, P. I.) 



The character of the recent outbreak of cholera in Manila 

 evidenced no indication of being one due to the spread of the 

 infectious agents by means of the water supply. 



As water is one of the most important factors in the dis- 

 semination of cholera, it was deemed of interest to arrange an 

 orientation experiment as given below. 



In order to gain some information as to the vitality of cholera 

 vibrios in Manila waters, the tap water and the sea water were 

 considered. Sterile distilled water was included for comparison. 



It is evident from the literature,^ as well as from theoretical 

 grounds, that the vitality of cholera vibrios in water will 

 be subject to variations owing to different factors, such as, 

 the temperature of water, the chemical composition of water, the 

 competition of cholera vibros with other bacteria present, 

 the number of cholera vibrios, and the physical condition of 

 the water. 



The consideration of the experimental evidence gives a certain 

 general idea as to the vitality of cholera vibrios in water; but 

 owing to the multiplicity of factors involved as well as to the 

 differences in local conditions it is impossible to apply the re- 

 sults of the experience gained elsewhere to local conditions in 

 a particular place. Therefore, it was thought more instructive 

 to arrange a simple experiment under such conditions as might 

 occur in this community. 



The following experiments were made : 



1. Series of 5 test tubes containing 10 cubic centimeters of distilled water. 



2. Series of 5 test tubes containing 10 cubic centimeters of tap water. 



3. Series of 5 test tubes containing 10 cubic centimeters of sea water were 



inoculated in such a way that 1 loopful of cholera faeces (typical rice- 

 water stool) was planted in the first test tube, 3 loopfuls in the second, 

 5 in the third, and so on. 



^ The results of experiments by various authors regarding the vitality of 

 cholera vibrio in water will be found tabulated in Kolle und Wassermann, 

 Handbuch der pathogenen Microorganismen (1903), 1, 196. 



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