Even disregarding what we can call "safe", a 3-in-a-million chance vs a 5,000-in-a-million chance is a significant gap. I think I read somewhere that of the fa

Even disregarding what we can call "safe", a 3-in-a-million chance vs a 5,000-in-a-million chance is a significant gap. I think I read somewhere that of the fairly wide-reaching trail of the Salk vaccine, 11 people died, and those were all traced back to a contaminated/not-correctly-processed batch from a lab in California, and that didn't temper the public's enthusiasm for the trials one bit.