The document outlines the steps for investigating an epidemic. It defines what constitutes an epidemic and lists different types. The key steps for an epidemic investigation include: 1. Verifying diagnoses of cases and confirming the existence of an epidemic. 2. Defining the population at risk by mapping cases. 3. Searching for all cases, including infected individuals and their contacts. 4. Analyzing collected data to form a hypothesis about the source and spread. 5. Evaluating environmental factors and testing the initial hypothesis. 6. Writing a final report with recommendations to prevent future epidemics.