Originally Posted by FTv3

None because no CoV’s are suspected to be transmitted primarily through the airborne transmission route.
SARS was droplet AND had a prototype vaccine developed AND it was contained largely because transmission links were clear and the chains could be broken. MERS is close contact and has a phase 1 clinical trial vaccine. The other 4 strains of coronaviruses that infect humans account for 15% of global common cold infections. If you can find research suggesting these are airborne please share. I couldn’t. I did find almost unanimous information saying that common colds are transmitted through respiratory expulsion of droplets (via sneezing and coughing), fomites, touching contaminated surfaces then touching your own face kind of thing. My unresearched opinion there is no vaccine for these is ROI based and no clear need.