If they continue to have reactions from people who had no prior history of anaphylaxis that will force them to give vaccine in hospital settings only. If they can't figure out why or perhaps its an issue with this mRNA class vaccine then may see issues with Moderna's version also. Not to negatively speculate but already a delay in shipments, possible limitations to setting it can be administered could equal long delays. Really have to wonder if this gets substantially delayed into fall or early next winter to vaccinate a decent percentage of the population will alot of the population already have been exposed anyways. With infection rates the way they are now it seems so many people will have been exposed it might be better to filter people through an antigen test and prioritize vaccination of those who still haven't been exposed. Would still expect frontline workers, nursing homes, people over 65 etc.. to get it first. But once into general population maybe a different strategy?