Buildings are getting tested for coronavirus, too. Research teams in Oregon are conducting real-time coronavirus tests on ventilation systems in buildings that could be essential for returning to the office or school. Plus, small businesses are facing an existential threat. And, in a rare move, the Trump administration rescinds a recent guideline that would have sent hundreds of thousands of international student packing. Guests: Axios' Joann Muller, Dion Rabouin, and Mike Allen.Credits: "Axios Today" is produced in partnership with Pushkin Industries. The team includes Niala Boodhoo, Sara Kehaulani Goo, Carol Alderman, Cara Shillenn, Nuria Marquez Martinez, Naomi Shavin and Alex Sugiura. Music is composed by Evan Viola. We can be contacted by email at podcasts@axios.com.Go deeper: Buildings are getting tested for coronavirus, too The existential threat to small business Trump administration rescinds foreign student visa guidance