USA, Natural immunity key
https://covid.cdc.gov/covid-data-tracker/#nationwide-blood-donor-seroprevalence
Nationwide Blood Donor Seroprevalence Survey
Data, gathered from blood donors
Estimates of population, 16 and older, have developed antibodies
Vaccination or infection?
March 21st 2021
Seroprevalence, 49.1%
Over 16 vaccinated, 13.7%
Cumulative reported cases, 8.7%
Deaths as of 21 March
https://covid.cdc.gov/covid-data-tracker/#trends_dailytrendscases
550,559
US population, 330 million
Total infections, 162,000,000
Infection fatality rate, 0.4% (0.33985)
Infection fatality rate as of 21st March
Now, herd immunity
Adults with at least one vaccine dose, 64.7%
US hospitalizations
https://covid.cdc.gov/covid-data-tracker/#new-hospital-admissions
Total now, 2,255,380
Source