Herd Immunity, COVID-19 and Vaccination: Some Propositions

In the backdrop of the Great Barrington Declaration and the John Snow Memorandum, a critical look into the math of herd immunity for COVID-19 suggests that the goal should be to reach the threshold through multiple interventions, that any vaccine intervention should show efficacy beyond the threshold for relative and absolute risks in and beyond trials, that recognizing proximate impact, introducing public provisioning and focusing on groups with greater exposure can all reduce the proportion required for direct intervention to reach the threshold. Besides recognizing the advantages of natural immunity, the ethical imperative requires no excessive focus on a single disease or type of care and does not mandate any specific care.