My grandmother, her mother, knew about it too.
People in previous generations who were thoughtful knew what the plague or Spanish flu really was. Everyone was healthy until they were vaccinated, but after the vaccination they usually got very high fevers and then died. Both grandmothers told me about it.

Years ago, out of curiosity, I got employed at SUKL (State Institute for Drug Control https://en.wikipedia.org/w... ) and there I learned so many interesting things from the people in the approval department (laboratories) that it only confirms this thesis.

If you get vaccinated, you are much more likely to get the disease than if you are not vaccinated! And the side effects (the actual active ingredients) - the heads of doctors and politicians would be rolling in the streets if people were told the whole truth.