Why outbreaks like coronavirus spread exponentially, and how to "flatten the curve"

Linked on March 16, 2020

Harry Stevens, at The Washington Post, with my favorite explanation from over the weekend of why this virus is so dangerous and how it spreads:

[...] these simulations vastly oversimplify the complexity of real life. Yet just as simulitis spread through the networks of bouncing balls on your screen, covid-19 is spreading through our human networks — through our countries, our towns, our workplaces, our families. And, like a ball bouncing across the screen, a single person's behavior can cause ripple effects that touch faraway people.

The visuals in this piece are excellent.