I think this is what most doctors and nurses assumed, that if a product has made its way into their hands, then the people upstream have done their due diligence for it to get there.

The duty and responsibility for ascertaining the quality of the consent rests upon each individual who initiates, directs, or engages in the experiment. It is a personal duty and responsibility which may not be delegated to another with impunity.

It says there in the Nuremberg codes, that if you're going to inject someone you have a personal responsibility to know what the effects of that will be.