During the first half of this course, students are introduced to basic epidemiological concepts and methods, which form part of the standard armament of all epidemiologic activity. This includes the most common measures of disease frequency, measures of effect, basic study designs, concepts of validity, and basic statistical concepts. In the second half, emphasis is placed on how these basic tools are applied in the disease dependence context typical of infectious disease epidemiology. In this part of the course, students will look at models for epidemics, outbreak investigation and analysis, surveillance, measurement of infectivity, contact patterns, and the epidemiology of vaccination. An effort will be made to demonstrate the application of these methods in the context of important infectious diseases of human, animal, and zoonotic origin.