People wait in a line on New Year’s Eve to receive a COVID-19 vaccination at a site for seniors in an unoccupied store at the Oviedo Mall. Governor Ron DeSantis ordered that Florida residents 65 and older be included in the first group to be offered coronavirus vaccinations, against the federal CDC recommendations.Paul Hennessy | LightRocket | Getty ImagesThe head of the Food and Drug Administration said Friday he is urging states to begin vaccinating lower-priority groups against Covid-19 as U.S. officials try to pick up the pace after a slower-than-expected initial rollout.FDA Commissioner Dr. Stephen Hahn did not advise opening vaccinations to all Americans, telling reporters that states should give shots to groups that “make sense,” such as the elderly, people with preexisting conditions, police, firefighters and other essential workers.”We’ve heard in the press that some folks have said, ‘OK, I’m waiting to get all of my health-care workers vaccinated. We have about 35% uptake of the vaccine.’ I think it reasonable to expand that” to other groups, Hahn said Friday morning during an event hosted by the Alliance for Health Policy. “I would strongly encourage that we move forward with giving states the opportunity to be more expansive in who they can give the vaccine to.”Hahn stressed the distribution of the vaccines still needs to be driven by “data and science,” adding that states ultimately know what’s best for their communities.The Centers for Disease Control and Prevention has provided states with an outline that recommends prioritizing health-care workers and nursing homes first, but states can distribute the vaccine as they see fit. But in recent days, U.S. health officials have expressed concerns that the national guidance may be slowing the pace of vaccinations as states limit access to shots to certain people.More than 21.4 million doses of vaccine had been distributed across the U.S. as of Thursday, but just over 5.9 million doses have been administered, according to data compiled by the CDC. The number is a far cry from the federal government’s goal to inoculate 20 million Americans by the end of 2020 and 50 million Americans by the end of this month.Earlier this week, Health and Human Services Secretary Alex Azar advised states against “micromanaging” their allotted vaccine doses, saying it’s better to get the shots out as quickly as possible.”There is no reason that states need to complete, say vaccinating all health-care providers, before opening vaccinations to older Americans or other especially vulnerable populations,” Azar told reporters during a news briefing on Wednesday.”If they are using all the vaccine that is allocated, ordered, distributed, shipped and they are getting it into health-care providers arms, every bit of it, that’s great,” he added. “But if for some reason their distribution is struggling and they are having vaccine sit in freezers, then by all means you ought to be opening it up to people 70 and older.”Global health experts had said distributing the vaccines to some 331 million Americans in a matter of months could prove to be much more complicated and chaotic than originally thought. The logistics of getting the vaccine and administering it are complex, requiring special training. Pfizer’s vaccine, for example, requires a storage temperature of minus 94 degrees Fahrenheit. On a press call Thursday, state health officials said they were working to administer the vaccine as quickly as possible, but blamed insufficient funding and lack of communication from the federal government for the slowdown.They said they expected the rate of vaccinations to pick up once Johnson & Johnson’s vaccine was authorized. J&J’s vaccine only requires one shot, while Pfizer’s and Moderna’s vaccines require two doses about three to four weeks apart.U.S. officials acknowledged vaccine distribution has been slower than they had hoped. Dr. Nancy Messonnier, director of the CDC’s National Center for Immunization and Respiratory Diseases, told STAT News on Tuesday that she expects the vaccine rollout to speed up “pretty massively” in the coming weeks.”It’s the early stages of a really complicated task, but a task that we’re up for,” she told STAT.