82 ILLINOIS ACADEMY OF SCIENCE 
THE PREVENTION OF DISEASE 
Dr. CLARENCE W. East, 
District HEALTH OFFICER, ILLINOIS STATE BOARD 
oF HEALTH 
This title is broad, and I have taken the privilege of using 
only a portion of it, that which by inference applies to the 
communicable diseases. 
Occupational diseases, diseases due to neoplasms, degenera- 
tive diseases due to the wear and tear of life, to dietary faults 
and to narcotic drugs, surgical conditions and a considerable 
number of other morbid conditions cannot be further referred 
to. 
CoMMUNICABLE DISEASES 
One. Isolation and Quarantine. 
The oldest and most generally effective measures for the 
control of communicable diseases are isolation and quarantine. 
The rationale of these measures has a three fold basis, viz: 
1. Prevention of contact. A large proportion of these 
diseases depend for their dissemination upon contact of the 
patient with other humans. 
2. Biological antagonism resulting in germ death. An 
attacking force of pathogenic organisms is successfully com- 
batted by the defensive forces of the human body and usually 
perishes in toto in the case of a large number of diseases which 
are styled “self-limited.” 
3. Disinfection of discharges. Body discharges may be 
disinfected when proper isolation is maintained, thus destroy- 
ing a common source of disease spread. 
Specific Instances, 
There are no communicable diseases in regard to which 
quarantine and isolation are not enormously useful measures, 
and there are some in relation to which these are our chief and 
perhaps only preventive agencies. Among the more common 
of such are measles, scarlet fever, mumps, chickenpox and 
whooping cough. 
