Moderna, without specifically commenting on the effectiveness of a fourth shot, said its submission was partly based on data recently published in the United States and Israel following the emergence of the Omicron variant. FDA did not immediately respond to a Reuters request for comment.
U.S. health officials, including top infectious disease expert Dr. Anthony Fauci, have raised the prospect of a fourth shot, especially for older people and to prepare for the possibility of another surge in cases. CDC data has shown that vaccine efficacy wanes over time and a third shot helps restore it. It, however, has not released comprehensive data based on age or health status to back the case. The news was first reported by the New York Times.