The built environment often shapes the spread of disease. Many early cases of COVID-19, the 2019 novel coronavirus, centered on a seafood market in Wuhan City, China. Airports, hospitals and other gathering points can easily become sites of virus transmission. But as the world grapples with the COVID-19 outbreak, Hongxi Yin, associate professor in advanced building systems and architectural design at Washington University in St. Louis, is exploring whether using portable furnaces to sterilize contaminated building exhaust might help to stem the contagion.