6 ms·
Herd immunity for COVID-19 is 60-85% of the population. (The formula is 1 - 1 / R0; intuitively, the average person spreads the virus to R0 other people, so if
by nostrademons 6y ago
Herd immunity for COVID-19 is 60-85% of the population. (The formula is 1 - 1 / R0; intuitively, the average person spreads the virus to R0 other people, so if only 1 / R0 people are still susceptible, effective R = R0 * 1 / R0 = 1 and the epidemic reaches a steady-state instead of growing.) NYC antibody tests have indicated about 20% immunity. They're still a long way away from herd immunity.