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White House tells states to prepare for Covid vaccinations in young children
By Shannon Pettypiece
Moderna Argues to F.D.A. for Half-Dose of Vaccine as Booster
By Sharon LaFraniere
A primer on what we know about mixing and matching Covid vaccines
By Helen Branswell
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U.S. FDA staff says Moderna did not meet all criteria for COVID-19 boosters
By Michael Erman & Julie Steenhuysen
Pfizer-BioNTech Covid-19 Vaccine Is World's Preferred Shot
By Jared S. Hopkins & Alice Uribe
Fully Vaccinated and Had Covid-19? No Rush for a Booster Shot, Experts Say
By Felicia Schwartz
U.S. will accept WHO-approved COVID-19 vaccines for international visitors
By David Shepardson