>The CDC's guidance is that everyone has a single shot of the "updated" vaccine which has higher efficacy against omicron/later strains -- no matter how many va

>The CDC's guidance is that everyone has a single shot of the "updated" vaccine which has higher efficacy against omicron/later strains -- no matter how many vaccines they've previously had. The CDC is making the claim everyone should get the updated shot vs previous. They made that claim without any human trial data comparing the two. Work has been done subsequently comparing bivalent to monovalent immune response; they are about the same.