The earliest confirmed cases Spanish Flu were at a army base is in Kansas, per Wikipedia, which is the zenith of intellectual inquiry.
There is increasing evidence that a conventional type vaccine will not be effective as many post infected individuals have no related antibodies, however, they do show a build up of T-cells. So expected first a conventional vaccine of the inactivated COVID-19 virus which will provide partial short term protection and no efficacy past four months +/-, and eventually t-cell therapy which will of some effect in treating active cases and providing some protection in fending off the virus, but not vaccine-like immunity, and it will be expensive. In other words, this is the new normal for years.