Few things are as haunting as tracking a viral outbreak through the cascade of headlines detailing worsening statistics, cities under lockdown, closed borders, canceled flights, evacuations and quarantines. More than 12,000 people have now been infected by the Wuhan coronavirus, mostly in China but in 26 other countries too, and more than 250 have died. Viral outbreaks are a tragic unintended consequence of at least three factors crucial to human ...