NPR News: Why Tens Of Thousands Of People Are Key To Testing A COVID-19 Vaccine

Why Tens Of Thousands Of People Are Key To Testing A COVID-19 Vaccine
Volunteers getting the shot help determine if a candidate vaccine works. But what with social distancing and masks, scientists must discern if it's the shot or these other measures preventing illness.

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at September 23, 2020 at 04:00PM
Health & Science