I’ve built true-to-life computer models capturing how fear works in people and how it spreads through human societies. The best advice these models have to offer right now is that we need to think about the novel coronavirus as four separate epidemics: In addition to the Covid-19, itself, we are also in epidemics of fear about the virus, fear about the economy, and likely soon, fear about a new vaccine. All four contagions are closely intertwined and will interact to amplify each other in complex ways.

To get the world back on track requires controlling all four horsemen of the Covid-19 apocalypse—which makes the response far more complicated than leaders seem to appreciate.

It will involve overlapping and ongoing responses: continued distancing and testing of people for infection; rapid fielding of a new antibody test to determine immunity so people can go back to work safely; development of a safe effective vaccine to keep Covid-19 permanently at bay; and—importantly—a persuasive information campaign, even before it arrives, against needless fears of vaccination. This combination offers the best chance of winning the long game against Covid-19.