What does it take to Ebola-proof a hospital? Over the past few months, U.S. medical centers have spent millions of dollars putting together a plan to treat patients with the scary, but extremely rare disease. To a large extent, it has been an exercise in improvisation. In Newark, New Jersey, a hospital dealing with a space-crunch and staff anxiety moved its Ebola operation out of its main building and into a mobile medical shelter ordinarily used during natural disasters. In Dallas, Texas, three hospital systems pooled resources to create a treatment center in a defunct intensive care unit sitting empty since the spring.