1. Health

Infectious Disease Basics

Infectious diseases are caused by many different kinds of microbes and parasites. Learn how viruses, bacteria, protozoa, fungi, and other parasites differ from each other, and how your body's immune system defends against infection. Find out their impact on society.

Diagnosis of an Infection: Microbial Cultures
Infectious diseases often require diagnosis using a culture of a sample from the infected site. What is a culture, and how is it used to diagnose an infection?

Epidemiology 101: Outbreak Investigation
What exactly is an outbreak, and why is it important to investigate it? What do epidemiologists do when investigating an outbreak?

What is a Virus?

What are Bacteria?

The Immune System

The Immune Response


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