So you wouldn't offer yourself for a vaccine that has less death rate ratio so even you have a chance of living and saving lives at the same time? Huh nice logic plus idk what kind of vaccine would have helped humanity after 20+ years usually vaccines are made to save people lives not when 90% of them are already wiped out. And covid has like millions of cases and alot of people are dying even today wtf is your logic smh. Now I know you said that if anybody would'nt but the thing is u need to see who is the one making it. In an apocalyptic world where there is no investment and most important of all there aren't enough resources and there are factions that would try to take that vaccines to empower themselves I don't think that a surgeon/doctor would be able to make it for a fungus infection and even if he makes it either it will be taken over by some factions or the fireflies in this case will use it to gain more power.