Covid-19 vaccines rolling out in the United States, the United Kingdom and other parts of the world so far require two shots given a few weeks apart.In the US where vaccines from Pfizer and Moderna are being distributed, health officials say the two aren't interchangeable even though they're made similarly.Also Read | The Indian-Americans driving Biden’s agendaIn “exceptional situations" when the same kind isn’t available or if it’s not known what was given for the first shot, the U.S.
Centers for Disease Control and Prevention said in recently updated guidance that it’s OK to give whichever vaccine is available for the second shot.The agency noted that the recommendations could be updated as more information becomes available, or if other.