1-19. CONTROL OF THE DISEASE SOURCE
One means of breaking the chain of disease transmission is through measures
for controlling sick individuals (cases), carriers, and animal reservoirs. These control
measures include isolation, quarantine, medical surveillance, treatment, and personal
a. Isolation. Isolation is a procedure whereby infected persons (cases or
carriers) are separated from other individuals. Usually this separation is accomplished
by having the patient admitted to the isolation ward in the hospital. Clothing and linens
used by infected individuals are laundered with soap and hot water. Other
contaminated articles are washed, scrubbed, aired, sunned, or incinerated as
appropriate to the article. Mattresses and pillows used by apparently well persons
should be sunned at intervals to destroy and bacteria that may be on them.
b. Quarantine. Quarantine is the restriction of freedom of movement of those
individuals who may have been in contact with a case and who may themselves
develop and further spread the disease. In this case, the individual is only suspected of
having a contagious disease; however, if an individual is known to have a disease of a
communicable nature, he may likely be placed in isolation rather than in quarantine.
c. Medical Surveillance. This measure may be carried out in two ways:
(1) When cases or suspected cases of certain communicable diseases
occur in a command, all persons who are their contacts may be inspected daily during
the incubation (developmental) period of the disease in order to detect new cases of the
disease that may be developing.
(2) In the presence of a threatened epidemic, examinations of all troops
may be ordered at stated intervals for the purpose of detecting early cases.
d. Treatment. When discovered, all cases of disease are treated. In this way,
the disease agents are destroyed and will not spread further.
e. Personal Hygiene. The spread of disease agents from infected individuals
can be prevented or greatly reduced by careful observance of the rules of personal
hygiene--by strictly adhering to healthful habits and practices.
f. Animal Reservoirs. Control of animal reservoirs which tend to live in close
proximity to man will do much to reduce the communicable disease hazard. Rats are
reservoirs for a number of diseases, including plague, leptospirosis, murine typhus,
enteric salmonellosis, rat bite fever, and trichinosis. They may transmit these diseases
to humans through fleas, by contaminating food or water, or by other means. Mice also
are health hazards. Rats and mice should be exterminated; the usual method is by
poisoning. In addition, denying rodents access to food, water, and shelter will prevent
new colonies from being established in the area. Quarantine and immunization of