Many unanswered questions remain about the vaccine: “It’s also unknown whether any of the 94 coronavirus patients had underlying risk factors. That data matters because state and county officials are prioritizing high-riskand socially vulnerable groups during the first distribution waves. “It’s not clear in the trial who got the vaccine,” says Paul Offit, director of the Vaccine Education Center at Children’s Hospital of Philadelphia and a member of the FDA’S COVID-19 advisory committee. “You wonder whether those groups of people were adequately represented.”