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.
More than 100,000 people are taking part in studies to see if one or more COVID-19 vaccine candidates actually work.
Janssen Pharmaceutical Cos. of Johnson & Johnson is about to start wide-scale testing for its vaccine. It will involve as many as 30,000 volunteers. AstraZeneca, Pfizer and Moderna already have vaccine candidates in large studies in the United States. Novavax should start its study later this fall.
The reason the trials are so large has to do with the complications of getting an accurate analysis of whether the vaccine works —
