It would be of particular interest to understand how many people may have unknowingly contracted COVID and had such mild symptoms (or none whatsoever) that they were never even tested. Would one assume that those people have already built up (or already had) immunity? Wouldn’t it make sense to then test those people for immunity and then take them off the list for vaccination? Is there even a test currently to test for immunity? And what about people that had COVID and recovered, is there any reason for them to be vaccinated?