10 SANITARY PRIVY. 
water or food supplies, and then be swallowed by and cause infec- 
tion in persons. They may be carried by drainage or seepage or 
tracked on the feet of persons, live stock, and poultry to the well 
or spring. They may be carried directly by flies from the excreta 
to the foods in the kitchen or dining room. If spread about the 
place they will from time to time get on the hands of persons, and 
thence into the water or foods. . 
Some of the ways in which typhoid germs in the excreta from 
infected persons may be conveyed to other persons are shown in the 
following diagram: 
Diagram of modes of spread of typhoid fever. 
Typhoid ing erases ade 
patients or 
Excreta from ..., Typhoid} to Water -.-.- Sette ek 
germ MANS. age 52 eR. of 
carriers Raw vegetables and persons 
Roods 220 (irunts: 235 oe 
The foregoing diagram shows that the easiest way of protecting 
against typhoid fever is to dispose of the excreta in such a manner 
that the germs contained therein can not be spread. This can be 
done by using sanitary privies. 
Dysentery and diarrhea (“summer complaint ”).—Dysentery and 
similar infections can be prevented in the same way as typhoid fever, 
as their method of spread is the same. 
Tuberculosis—Although the danger of spreading tuberculosis by 
spitting must be constantly held in mind, it is important to remem- 
ber also that many tubercle bacilli may be discharged in the feces, 
because persons with lung tuberculosis (“‘ consumption ”) frequently 
swallow their sputum, and also because some persons have tubercu- 
losis of the bowels. The spread of tuberculosis by soil pollution may 
be prevented by using sanitary privies. 
PARASITIC DISEASES. 
Among the diseases caused by animal parasites, and spread by soil 
pollution from man to man, there may be mentioned, especially, hook- 
worm disease, Cochin-China diarrhea, eelworm infection, pinworm 
infection, blood-fluke infection, amcebic dysentery, and many other 
diseases. In some of these maladies the infection is spread in much 
the same way as is that of typhoid fever, the germs being swallowed ; 
in others the infection may take place through the skin. All of these 
diseases can be prevented by using sanitary privies. 
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