The Contagion Detective

Adam Kucharski virus graphic

Photo illustration by Mark Riechers. Original images by CDC and via the author. 

The COVID-19 pandemic was some epidemiologist’s nightmare when Adam Kucharski was writing "Rules of Contagion." The book, which includes brief mentions of the encroaching COVID-19 storm, draws on ideas from “outbreak science” to illuminate how and why viruses spread. Information from biology, Kucharski expertly demonstrates, has helped scientists understand how misinformation rages like fire in the fields of politics and finance. Kucharski is entitled to feel like Nostradamus, but people in his field “always have the next pandemic on the radar,” he told Wired.

I caught up with Kucharski to learn about the key ideas in "Rules of Contagion," and hear his latest views on the COVID-19 outbreak. He believes we’re still in the early stages—not even the mid-point—of this global pandemic.

You can read the full conversation over on Nautilus. Here's an excerpt: 

Steve Paulson: You are both an epidemiologist and a mathematician by training. Why are mathematical models so helpful in understanding pandemics, including COVID-19?

Adam Kucharski: Mathematical models are a useful way of laying out the knowledge we have about an infection, and laying out the assumptions we can make about transmission. We look at the magnitude of transmission from person to person. We capture a reproduction number, the average number of new cases generated by an existing case. We also look at time scale. It’s the time between one person showing symptoms and the person they infect. These two things together give you the amount of growth at each step, and then the other tells you how quickly those steps are occurring.

SP: As you look at those two factors and look at COVID-19, what do you see?

AK: That people can infect others very early in their infectious period means that that time scale can be quite short. We know that one case can infect two or three others, even if everyone is back to normal and behaving as they were. That means you can get an epidemic that potentially is doubling every three or four days. There’s potential for super-spreading events. You can get these large exposure events, where a lot of people suddenly become infected in a workplace or in a bar, and that means your outbreak really does accelerate. Certainly in all the epidemics I’ve faced, this is the toughest. This is something that’s unique in the last 100 years.

You can read the whole conversation — including what a pandemic has in common with the 2008 financial crisis and misinformation spread on Facebook — over on Nautilus.