88 
BACTERIOLOGY. 
Flies can deposit the infection on bread, butter, meat, 
and other foodstuffs. Direct infection from handling 
soiled bed-linen is not uncommon, as is shown by the 
greater frequency of the disease among washerwomen 
during epidemics. The onset of cholera, following an 
incubation period of two to five days, is sudden, with 
frequent watery stools, high fever, and great prostra¬ 
tion. In the severe cases death may occur in eight to 
twelve hours. The infection localizes itself in the 
intestine. The spirilla are never found in the cir¬ 
culating blood, consequently the stools alone are in¬ 
fectious and may continue to be for months after re¬ 
covery. People who carry the spirilla of cholera in 
the intestine after recovery are called cholera carriers. 
To prevent the disease during epidemics all 
drinking-water and milk must be boiled, and no meat 
or vegetables eaten unless cooked. Great care must be 
taken to exclude flies from contact with foods. Bed- 
linen, clothing, and utensils used by patients should be 
soaked in 5 per cent, carbolic solution, and subse¬ 
quently boiled in the laundry. Attendants upon 
cholera patients should be careful to disinfect the hands 
after handling the patients. The stools are best dis¬ 
infected with 5 per cent, carbolic solution, and the dis¬ 
infection should be continued for some time after re¬ 
covery. 
The constitutional symptoms that accompany 
cholera are due to the toxins formed by the spirilla in 
the intestines. They are partly thrown out by the 
organisms, that is, soluble toxins, and partly retained 
