Heeney and colleagues face a challenge that has long proved insurmountable for scientists: to develop vaccines that can not only protect against a single coronavirus, but multiple strains, varieties, and perhaps even entire families of them. A comparable feat has never been managed in the history of virology, after more than two decades of chasing the same goal in influenza yielded little of note. Some have even compared the task"s ambition, scope and difficulty to the infamous Manhattan Project of the 1940s, which pushed the boundaries of physics at the time, and yielded the world"s first atomic bomb.