From a utilitarian standpoint doing human challenge trials for the covid vaccines would have been preferable to ecological / uncontrolled trials (for instance, we would have clearer data, today about the optimal dosage, which translates into maximizing the number of successful vaccinations from a given batch of the vaccine).
My current understanding for why the US didn’t do human challenge trials comes down to the incentives of the decision makers: they are likely to experience some backlash, especially if something goes wrong, but they don’t gain accolades or other rewards for the massive upside.
From a utilitarian standpoint doing human challenge trials for the covid vaccines would have been preferable to ecological / uncontrolled trials (for instance, we would have clearer data, today about the optimal dosage, which translates into maximizing the number of successful vaccinations from a given batch of the vaccine).
My current understanding for why the US didn’t do human challenge trials comes down to the incentives of the decision makers: they are likely to experience some backlash, especially if something goes wrong, but they don’t gain accolades or other rewards for the massive upside.