In this activity, students will observe the spread of influenza in 2 hypothetical populations. The students will be able to see how influenza affects individuals of different ages and with different risk factors. They will compare the spread and outcome of influenza in a population where less than 20% are vaccinated to a population where greater than 70% are vaccinated. The students will each play a character in these hypothetical populations and the class will gather, analyze, and discuss data on prevalence, mortality, recovery, and vaccination rate.