> It would be unethical to hold back vaccinations from a control group for 2 years after it already proved efficacy. Is it? I don't remember reading about that

> It would be unethical to hold back vaccinations from a control group for 2 years after it already proved efficacy. Is it? I don't remember reading about that in NIH training on control groups. I'm pretty sure when your plan is to distribute 1 billion vaccines, holding out 0.000015 for a placebo control group is a sensible "ethical" tradeoff. Especially if, I don't know, everyone *volunteered* and agreed to those terms when signing up! And especially if, I don't know, all the data they had to date showed no increase in death rate?