One of the Best Books of 2020 -- Financial Times One of the "Most 2020 Books of 2020" -- Washington Post One of the Best Science Books of 2020 -- The Times of London One of the Best Science Books of 2020 -- The Guardian From ideas and infections to financial crises and fake news, an "utterly timely" look at why the science of outbreaks is the science of modern life These days, whenever anything spreads, whether it's a YouTube fad or a political rumor, we say it went viral. But how does virality actually work? In The Rules of Contagion, epidemiologist Adam Kucharski explores topics including gun violence, online manipulation, and, of course, outbreaks of disease to show how much we get wrong about contagion, and how astonishing the real science is. Why did the president retweet a Mussolini quote as his own? Why do financial bubbles take off so quickly? Why are disinformation campaigns so effective? And what makes the emergence of new illnesses -- such as MERS, SARS, or the coronavirus disease COVID-19 -- so challenging? By uncovering the crucial factors driving outbreaks, we can see how things really spread -- and what we can do about it. Whether you are an author seeking an audience, a defender of truth, or simply someone interested in human social behavior, The Rules of Contagion is an essential guide to modern life.