PROPHYLAXIS. 477 



amination of the stools of those who have been in 

 contact with cholera patients until their freedom 

 from vibrios is assured. 6. Frequent examination 

 of the water supply at different points in order to 

 detect the occurrence of water infection. 7. In 

 case water infection exists, exclusion of the water 

 from all domestic uses,, and the institution of 

 means to rid the water of infection. This may be 

 done in the case of infected wells, but in the case 

 of large systems reconstruction may be necessary 

 for future protection. Water for household use 

 should be boiled. Kolle compares the conditions 

 in Germany and Eussia during the epidemic of 

 1892-4. In Germany,, where Koch's principles of 

 prophylaxis were rigidly observed, about 10,000 

 cases occurred, 9,000 of which were confined to 

 Hamburg, whereas in Eussia, where precautions 

 were not enforced strictly or generally, 800,000 

 cases developed during the same period. 



Protective inoculation has shown itself to be of vaccination. 

 distinct value for prophylaxis. Ferran, a Span- 

 iard, first practiced vaccination on a large scale in 

 1884, although little definite knowledge of the 

 value of the procedure resulted from his work. 

 He is supposed to have used impure cultures. Haff- 

 kine introduced protective inoculation on a large 

 scale in India, and up to 1895 had inoculated 40,- 

 000 persons. Following Pasteur's method with 

 anthrax, he used two vaccines. Vaccine 1 was a 

 culture which had been attenuated by prolonged 

 growth at 39 C. Vaccine 2, which was adminis- 

 tered five days later, was a virulent culture. The 

 , living organisms were used in both vaccines and 

 the injections were given subcutaneously. The 

 local and general symptoms were mild. Instead 



