This Sept. 2020 photo provided by Johnson & Johnson shows a clinician preparing to administer investigational Janssen COVID-19 vaccine. Johnson & Johnson’s long-awaited COVID-19 vaccine appears to protect against symptomatic illness with just one shot – not as strong as some two-shot rivals but still potentially helpful for a world in dire need of more doses. Johnson & Johnson said Friday, Jan. 29, 2021 that in the U.S. and seven other countries, the first single-shot vaccine appears 66% effective overall at preventing moderate to severe COVID-19. It was more protective against severe symptoms, 85%. (Johnson & Johnson via AP)