LESSON 1
INTRODUCTION TO DISEASE TRANSMISSION AND EPIDEMIOLOGY
1-1.
GENERAL
Disease and non-combat injury have plagued military commanders since time
immemorial. In every war or combat action in which the United States (US) has ever
participated, disease and non-combat injury have contributed far more to the
ineffectiveness of troops than have losses due to enemy action. A commonly held
misconception is that since the advent of antibiotics and advanced medical techniques,
disease and accident are no longer matters of major concern. Nothing could be farther
from the truth. Statistics show that during the heaviest periods of combat action since
the outbreak of World War II, hospital admissions caused by disease and non-combat
injury have exceeded those caused by battle injury by a ratio of from 3:1 to 19:1
(Table 1-1). Prior to World War II, these ratios were even less favorable. Much credit
for the improvement in the situation must be given to epidemiologists who discovered
the causes of many of the diseases that had ravaged troops for centuries. As more is
learned in the future, the number of needless deaths and illnesses will hopefully be
further reduced. The key to opening the door to further discovery of methods of disease
control is a thorough knowledge of the various agents of disease and the nature of
disease transmission.
War Period and Location
Disease and Non-Combat
Battle
Injury
Injury
Pacific Theater of
95%
5%
Operations Nov 1942 to
Aug 1945 (WWII)
European Theater of
77%
23%
Operations June 1944 to
May 1945 (WWII)
Korean War
83%
17%
July 1950 to July 1953
Vietnam War
81.8%
18.2%
1 Jan 1969 to 31 Dec
1969
Table 1-1. US Army hospital admissions during selected war periods.
MD0151
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