12 SANITARY PRIVY. 
PARASITIC DISEASES SPREAD FROM MAN TO LIVE STOCK AND 
THEN BACK TO MAN. 
At least two kinds of tapeworms are spread from man to live stock 
and back to man because of lack of sanitary privies. 
Beef-measle tapeworm.—This tapeworm, when harbored in the in- 
testine of man, lays thousands of eggs, which are discharged in the 
stools, and if scattered about may be swallowed by cattle. Here they 
cause “beef measles,” reducing the value of the beef. By eating 
measly beef man may become infected with this tapeworm. 
Pork-measle tapeworm.—The eggs of this tapeworm are passed in 
the stools of man and swallowed by swine, in which they cause 
“pork measles.” By eating such pork man may become infected 
with tapeworms. This tapeworm is especially dangerous, because 
if a person harbors it and pollutes the soil with his excreta containing 
the eggs, these eggs may be swallowed by persons and cause a serious 
disease known as “ pork measles” in man, which may cause blind- 
ness, insanity, and death. 
Both of these tapeworm infections can be prevented by the use 
of sanitary privies. 
HUMAN EXCREMENT AS A BREEDING PLACE FOR FLIES. 
Flies and many other insects feed upon and breed in filth, such 
as manure and human excrement. Whenever a fly is seen it is posi- 
tive proof of the existence of some filth in the neighborhood. It is 
much more filthy and much more dangerous to have flies in the 
kitchen and dining room than to have bedbugs in the bedroom. 
Flies can carry various disease germs to man. By so doing they 
kill thousands of people, especially babies, every year; therefore kill 
the flies and save the babies. 
Tf flies have access to human excrement, they not only feed upon it, 
but they lay their eggs in it. After a few hours the egg hatches out 
‘ a maggot; this feeds in the filth for several (about five) days and 
then forms a pupa; after about five days the adult fly comes out of 
the pupal case, feeds on the filth, and carries disease germs from the 
filth to the house, depositing these germs on the foods. Thus flies 
carry disease to people. A fly drops his excrement about once every 
41 minutes and may spread germs not only in this way, but also with 
his feet, wings, and mouth parts. 
Even if excrement containing fly maggots is buried under as much 
as 6 feet of sand, the maggots can crawl to the surface, bringing 
disease germs with them. 
Thus it is clear that if flies are kept away from human excrement, 
not only will they decrease in numbers, but they will be prevented 
from spreading certain diseases, such as typhoid fever. This can 
be done by the use of sanitary privies. 
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