(FILES) In this file photo taken on November 18, 2020 shows a bottle reading "Vaccine Covid-19" next to the Moderna biotech company logo. - The Moderna Covid-19 vaccine, which was recently demonstrated to have 94 percent efficacy, causes the human immune system to produce potent antibodies that endure for at least three months, a study showedon December 3, 2020. Researchers at the National Institute for Allergies and Infectious Diseases (NIAID), which co-developed the drug, studied the immune response of 34 adult participants, young and old, from the first stage of a clinical trial. (Photo by JOEL SAGET / AFP) / -- IMAGE RESTRICTED TO EDITORIAL USE - STRICTLY NO COMMERCIAL USE --
