I think maybe less harmful jabs were given to the initial victims, to allow for better optics to entice uptake by the larger population.
Excellent point, and I wouldn't be at all surprised. One ALMOST-fully-awakened friend keeps saying "I got the vax in February. Why am I not dead? Why do I know so many people who haven't had any adverse reactions?"
That really is the only point of contention between me and her. In all other areas, she would make a worthy Freeper.