It is an eerie coincidence that Adam Kucharski's book, The Rules of Contagion: Why Things Spread and Why They Stop, was released in Britain right before the coronavirus outbreak of December 2019. "I began work in 2016. It is unfortunate that it released at a time like this, when the world is battling a deadly virus," Kucharski, associate professor and Sir Henry Dale Fellow at the London School of Hygiene and Tropical Medicine, says in a Skype interview. "But, in a way, I am glad the book, which addresses the underlying principles that drive contagion, will create awareness."

Kucharski is a TED fellow, winner of the 2016 Rosalind Franklin Award Lecture and the 2012 Wellcome Trust Science Writing Prize and the author of The Perfect Bet: How Science and Maths Are Taking the Luck Out of Gambling. His latest work explains what makes things spread, why outbreaks look like they do, and how we can change what happens in the future. Kucharski uses math to understand the outbreak of Ebola, SARS, influenza, and now COVID-19. With statistics flying around, what are the ones that need our immediate attention? "The number of cases reported is dependent on how many people are tested. Often, stats don't reflect actual numbers. So, it is only and only the number of fatalities that determines the [extent of] transmission of the disease," he explains. He clarifies that if a death has occurred today, it means the infection occurred at least a month ago. "There is a delay from transmission to outcome [death]. So it is only figures of death that need our attention."