Oxford researchers, in partnership with AstraZeneca, started dosing the first volunteers in Florida on Friday, and 31 Americans received either the vaccine or a placebo throughout the weekend, as part of the clinical trial. "Look at the amount of lives that we lost. And I just don't want that to keep occurring," 23-year-old trial volunteer Jacob Serrano told CBS News chief medical contributor Dr. Jon LaPook. As the first American to be dosed with either the vaccine or its placebo from Oxford and AstraZeneca, Serrano has already lost seven family members to COVID-19 and says he wants to be part of the solution to save lives, no matter the cost. "I know there was a risk because it's like — it's a trial," Serrano said. "But I'd rather have us one step closer, no matter what it takes."