Understanding COVID-19 (Coronavirus): Part 3 – Herd Immunity

In an effort to increase understanding of the COVID-19 pandemic I am creating a series of 10-15 minute videos that: 1) explain some basic topics of epidemiology (3 videos) and 2) examine the evolving data as the pandemic develops through the lens of these basic epidemiological principles. This is the third video. It covers the concept of herd immunity. Part 1 explains S-I-R models. Part 2 explains the concept of a reproduction number, or R. Beginning with part 4, I interpret the evolving data using these three epidemiological concepts.