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RESPIRATORY DISEASES AND TROOP HOUSING
a. Common Respiratory Diseases. Respiratory diseases are the most
common disease threat in troop housing. Some of the respiratory diseases of concern
are influenza, acute respiratory disease, pneumonia, meningitis, tuberculosis, whooping
cough, and the common cold. This is not a complete list, but it gives a sampling of the
various respiratory diseases transmitted from person to person.
b. The Spread of Respiratory Diseases. Respiratory diseases are spread in
three basic ways.
(1) Direct contact between an infected person and a well person.
(2) Indirect contact with both living and nonliving things. Inanimate objects
(such as cups, spoons, and towels) are called fomites; living things (such as houseflies
and cockroaches) are termed vectors. Both can carry disease microbes. For example,
drinking from a sick person's cup or smoking the same cigarette can infect a well
person.
(3) Droplets from the respiratory tract of an infected person. Sneezing,
coughing, laughing, and even the normal breathing of an infected person project
disease-containing droplets (called droplet nuclei) into the air. Small droplet nuclei lose
their water content and remain airborne for many hours. Large droplet nuclei settle and
dry out, but the disease microbes do not die. Instead, they contaminate dust particles.
Both airborne and dustborne droplet nuclei are a source of infection.
(a) In an enclosed area, the degree of contamination from coughing,
sneezing, etc. is roughly proportional to the number of people in the room. A single
cough or sneeze may contain 40,000 or more disease carrying droplets. A small
number of sick persons could saturate the atmosphere of a closed room during an 8-
hour sleeping period.
(b) Dry nuclei may survive in bedding and in dust for several weeks or
months, particularly when the relative humidity is low. During sweeping, bedmaking,
and other housekeeping activities, dustborne organisms rise into the air and are inhaled
by the occupants of the room.
c. Exposure of Personnel to Respiratory Diseases.
(1) Respiratory diseases among recruits represent one of the most serious
medical problems the Army faces today. The radical change of life and living conditions
expose new soldiers to situations that challenge and lower their physiological defenses.
Because of this, recruits are extremely susceptible to respiratory diseases. As time
passes, they become "seasoned troops" and develop greater immunity against
respiratory diseases.
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