Before Covid-19 began spreading across the globe last year, virologist Nathan Wolfe already knew what was becoming abundantly clear: The world was woefully unprepared to prevent the spread of novel viral threats. To prevent similar devastation, he challenges people to imagine a different future where viruses are regularly tracked in groups of individuals—providing a sort of weather map of viruses. "We should have always-on systems that are capable of monitoring for all of the viruses present, all of the microbes present within a society, and that’s within reach." He speaks with Sarah Zhang, staff writer for The Atlantic, about where viruses come from, how to eliminate future pandemics, and why he doesn't think Covid-19 was deliberately released into the world. Wolfe is the founder and chairman of Metabiota and was a professor of epidemiology at UCLA.