US tops 450K deaths as CDC reports 'downward trajectory' in cases; Yankee Stadium to open as mass vaccination site: Latest COVID-19 updates.
John Bacon, Elinor Aspegren and Doyle Rice, USA TODAY
Experts including Dr. Fauci say double masking could help prevent COVID-19 spread
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A COVID-19 vaccine manufactured by the British-Swedish firm AstraZeneca appears to provide strong protection three months after just one dose while also curbing spread of infections, researchers said Wednesday.
British Health Secretary Matt Hancock said the study supports a strategy of delaying the second shot so more first doses can be delivered to more people. Researchers also found a 67% reduction in positive "swabs" among those vaccinated – crucial news because if no virus is present, the virus can't spread.