I believe that there was already some previous research done into making a vaccine for the original SARS and MERS (no vaccine itself made, just the research). So they must have had at least part of the Covid-19 genome sequenced already. It’s the clinical trials that take awhile because you’re literally moving at a biological pace, just waiting to see how effective it is or not. Fingers crossed! A highly effective vaccine would literally allow us to return to semi-normal life without face masks.