A nurse administers a shot at a COVID-19 mass vaccination site at Martinsville speedway in Ridgeway, Va., on March 12. Ashish Jha, a public health policy researcher, noted Sunday that “despite phenomenal vaccination rates, variants pulled ahead this week.”

A nurse administers a shot at a Covid-19 mass vaccination site at Martinsville speedway in Ridgeway, Virginia on March 12, 2021. – Community leaders, the heads of the Sovah Health hospital, and the speedway all came out to help and support the hospital nurses and the Virginia Department of Health in the mass vaccination campaign for this rural area in Virginia. The Virginia Department of Health said that vaccine distribution has been based on population and Covid-19 rates. But moving forward, the department said it is considering tweaks to ensure more geographical and racial equity in vaccine distribution. Health workers in the United States have administered more than 100 million Covid-19 vaccine doses, an official tracker showed on march 12. (Photo by ANDREW CABALLERO-REYNOLDS / AFP) (Photo by ANDREW CABALLERO-REYNOLDS/AFP via Getty Images)