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CHAMP, Fall 2015

Lesson 8

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Today we talked about spread of diseases and outbreaks. We learned about the reproduction ratio R₀ of a disease, and discussed the concept of herd immunity. To illustrate these concepts we played a game in which certain people in the classroom were infected and spread the disease to others, seeing the effects when different numbers of people are immunized.

• A Scientific American post on R₀, a very readable article on the reproduction ratio, which also describes how to calculate the percent of the population that must be kept immunized to keep a disease in check.
• The Wikipedia article on the Reproduction Ratio