A single dose of one of the currently available COVID-19 vaccines, even if less effective than two doses, may have greater population benefit, three research groups argued in three papers in Annals of Internal Medicine. In large trials, two-dose regimens of the vaccines from Pfizer Inc and partner BioNTech SE and from Moderna Inc both demonstrated nearly 95% efficacy in preventing illness from the coronavirus. In one of the new papers, Yale School of Public Health researchers say a less-effective single-dose might confer greater population benefit than a 95%-effective vaccine requiring two doses. In a second paper, University of Washington researchers say doubling vaccine coverage by giving a single dose to more people would hasten pandemic control by lowering transmission rates. And in a third paper, Stanford University researchers say delaying second doses in some people could enable millions more to receive a vaccine. "In a public health emergency, a powerful argument exists for doing something with less-than-perfect results if it can help more persons quickly," said Thomas Bollyky of the Council on Foreign Relations in an editorial published with the papers. "However, whether alternative approaches with current vaccines would accomplish this goal is far from clear." The U.S Food and Drug Administration said on Monday the idea of changing the authorized dosing or schedules of COVID-19 vaccines was premature and not supported by available data. —Reuters Staff Source
