Pfizer Says Its COVID-19 Vaccine Is 90 Percent Effective. What Happens Now?2020-11-09/in NewsDr. Stephenson clarifies why these results are noteworthy. Read Article https://cvvr.hms.harvard.edu/wp-content/uploads/2020/11/slate.jpg 400 400 Morgana Souza https://cvvr.hms.harvard.edu/wp-content/uploads/2020/03/cvvr-header-banner-long-white-bg.png Morgana Souza2020-11-09 09:07:292020-11-11 09:09:17Pfizer Says Its COVID-19 Vaccine Is 90 Percent Effective. What Happens Now?