Kill every human on the planet.
This is the first assignment I give students in my public health classes, filled with do-gooders passionate about saving the world. Their homework is to play a game called Plague, in which they pretend to be pathogens bent on infecting everyone on the globe before humans can develop a cure or a vaccine.
Why this assignment? Because as a professor of infectious disease epidemiology, I aim to teach students to think like pathogens so they can learn how to control them.
With COVID-19, thinking like a pathogen leads to an inevitable conclusion: Getting the vaccine out to everyone in the world as quickly as possible is not just an ethical imperative, but also a selfish one.