I think I was in 2nd or 3rd grade when all of us were given the vaccine in a sugar cube. I don't recall anybody in my school or in my extended family of cousins having any issues or knowing anybody who was affected. It seemed like a miracle at the time.
And that was shortly before thalidomide turned into a problem. Medical science, and science in general, has always had to deal with uncertainties, unknowns, and failure. Look at the relatively small number of failures in the space program from the 1950's and 1960's.
“And that was shortly before thalidomide turned into a problem.”
I watched a 2 hour documentary on this subject. Thalidomide is a magical cure for morning sickness. But when you make it in big batches, some percentage of the molecules get put together the wrong way, and it becomes instant birth defect formula. I think they called the property “handedness,” but my memory is fuzzy. It’s like quantum mechanics level creepy chemistry. Unintended consequences, not knowing what they didn’t know.