Evolution of Epidemiology

Modern Epidemiology

The modern approach in describing an infectious disease focuses on:

• the interaction of the disease agent,
• the host, and
• the environment

The disease agent, the host, and the environment interact dynamically to produce disease. All three of these are constantly changing.

Disease agent: Microorganisms adapt to changing conditions, including human control efforts such as antibiotics. There are many agents of disease and disabilities including:

• Biological agents such as bacteria and viruses.
• Nutritional components such as vitamin deficiency diseases and obesity.
• Physical forces such as radiation, chemicals, and fire.

In this course, however, we will be focusing on biological agents that will be covered more fully in other segments of the course.