Antonia da Silva Cruz Santos, 48, a nurse, a volunteer in COVID-19 vaccine trial for AstraZeneca, poses for a photograph in Sao Paulo, Brazil, December 08, 2020. "The first days after I took (the vaccine), I had a few symptoms – shivers and pain in my body. I had some bad thoughts, like what if I were intubated, I was always afraid of that … My daughter was desperate. She said 'Mom, you are crazy.' I said, 'No, crazy would be not to take it.'," Santos said. Picture taken with a slow shutter speed. REUTERS/Amanda Perobelli SEARCH "PEROBELLI VACCINE" FOR THIS STORY. SEARCH "WIDER IMAGE" FOR ALL STORIES