You are right that's not how the process of vaccination works....normally. This is an experimental technology being used and it does not create immunity like other vaccines. It also lacks the long term studies other vaccines have gone through therefore everyone in the world is in a worldwide vaccine study, meaning they are or are suppose to be monitoring the problems that occur in this one shoe fits all vaccine attempt. You have to remember one vital point, that being there is no medicine over the counter or behind the counter that doesn't come with warnings on who should or should not be taking it. So given that, in this instance the warnings for a whole lot of people will come way to late.