Michelle Chester, director of employee health services at Northwell Health, prepares the Moderna Covid-19 vaccine at Northwell Health's Long Island Jewish Valley Stream hospital in Valley Stream, New York, on Monday, December 21, 2020. AP
Michelle Chester, director of employee health services at Northwell Health, prepares the Moderna Covid-19 vaccine at Northwell Health's Long Island Jewish Valley Stream hospital in Valley Stream, New Show more

New vaccines launch in US amid fears of fast-spreading Covid-19 variant