Microbiology, 2021

CHAPTER 16
Disease and Epidemiology
Figure 16.1 Signs like this may seem self-explanatory today, but a few short centuries ago, people lacked a basic
understanding of how diseases spread. Microbiology has greatly contributed to the field of epidemiology, which
focuses on containing the spread of disease. (credit: modification of work by Tony Webster)
Chapter Outline
16.1 The Language of Epidemiologists
16.2 Tracking Infectious Diseases
16.3 Modes of Disease Transmission
16.4 Global Public Health
INTRODUCTION In the United States and other developed nations, public health is a key function of
government. A healthy citizenry is more productive, content, and prosperous; high rates of death and disease,
on the other hand, can severely hamper economic productivity and foster social and political instability. The
burden of disease makes it difficult for citizens to work consistently, maintain employment, and accumulate
wealth to better their lives and support a growing economy.
In this chapter, we will explore the intersections between microbiology and epidemiology, the science that
underlies public health. Epidemiology studies how disease originates and spreads throughout a population,
with the goal of preventing outbreaks and containing them when they do occur. Over the past two centuries,
discoveries in epidemiology have led to public health policies that have transformed life in developed nations,
leading to the eradication (or near eradication) of many diseases that were once causes of great human
suffering and premature death. However, the work of epidemiologists is far from finished. Numerous diseases
continue to plague humanity, and new diseases are always emerging. Moreover, in the developing world, lack