Ripped from an article by an MD on the American Lung Association site:
by David G. Hill, M.D. | July 27, 2020
Topics:
As
COVID-19 continues to spread through the United States, I have often heard people saying that "it just needs to run its course.” This, coupled with reports, disputed by some, of people attending so-called “COVID parties,” contribute to harmful misperceptions on the concept of herd immunity.
Herd immunity is achieved when large percentages of a population
become immune to a disease and therefore indirectly protect those who do not have immunity. If, for example, four out of five of the people who are exposed to someone with an infectious disease are immune to it, the disease is much less likely to spread. However, the percentage of people who must be immune in order to achieve herd immunity varies based on multiple factors including the mode of transmission, and how easily and quickly a given disease spreads.
In most cases, herd immunity is not achieved without an effective vaccine. For COVID-19, the percentage of the population that needs to be infected to achieve herd immunity is estimated to be between 70% and 90%, and this is assuming lasting immunity is possible.
Uhhhhmmm....mmmmkay.