“ There are two possible approaches to build widespread SARS-CoV-2 im- munity: (1) a mass vaccination campaign, which requires the development of an effective and safe vaccine, or (2) natural immu- nization of global populations with the virus over time. However, the consequences of the latter are serious and far-reaching—a large fraction of the human population would need to become in- fected with the virus, and millions would succumb to it. Thus, in the absence of a vaccination program, establishing herd immunity should not be the ultimate goal. Instead, an emphasis should be placed on policies that protect the most vulnerable groups in the hopes that herd immunity will eventually be achieved as a byprod- uct of such measures, although not the primary objective itself.”

https://pubmed.ncbi.nlm.nih.gov/32433946/