Getting a coronavirus vaccine in record time is hard. Distributing it to tens of millions may be equally daunting.

Getting shots into the arms of millions of Americans is a massive undertaking, they say, requiring extraordinary coordination, planning and communication. But with only six months to the government’s target date for approving a vaccine, the administration has shared limited and often confusing information about its plans for distribution, making it difficult for overwhelmed state and local officials, including those who run immunization programs, to prepare.

“It’s probably the hardest thing they’re going to do,” Paul A. Offit, director of the Vaccine Education Center at Children’s Hospital of Philadelphia and a member of a federal vaccine advisory group, said of the effort to distribute vaccines to every corner of America and immunize as many people as quickly as possible.

At a recent briefing for the advisory group by Operation Warp Speed, the administration’s effort to fast-track development of coronavirus countermeasures, Lt. Gen. Paul Ostrowski, who oversees logistics, said the military would move vaccines onto trucks for distribution “the day after” the drugs received regulatory approval from the Food and Drug Administration, Offit recalled.

But Offit said that was based on the administration’s inability to develop a national testing strategy, secure adequate supplies of personal protective equipment and deliver a consistent message about wearing face masks, the question he wanted to ask Ostrowski but didn’t have the chance was basic: “Given that the administration efforts have largely been failures, what makes you think this will work?”

Other experts expressed similar worries.

“This is a slow-motion train wreck,” said one state official who has been involved in planning efforts and spoke on the condition of anonymity to discuss a sensitive matter. The official pointed in particular to the administration’s botched rollout of remdesivir, an antiviral medication that is one of the only approved treatments for covid-19 patients. “There’s certainly a lot of concern, and not being able to plan creates a significant amount of confusion,” the official said.

The National Governors Association, a policy group representing both Republican and Democratic executives, urged governors Monday to start planning for the vaccine effort now, noting the “high degree of uncertainty as to the exact processes and procedures that will be used for operations, administration, and logistics,” according to a policy memo.

“Immunizing the U.S. population against covid-19 will likely require the single largest vaccination campaign ever undertaken,” the memo said.

Administration officials said coordination efforts are underway to address these concerns.

“Our team is working relentlessly and deliberately to deliver substantial quantities of a safe and effective vaccine to Americans,” a senior administration official said at a briefing Thursday organized by the Health and Human Services department, the lead agency for the pandemic response. The official spoke on the condition of anonymity, part of the ground rules set by HHS officials.

HHS and the Defense Department have a “synergistic teamwork” in logistics and planning that allow officials to assess risk and potential delays and “address them accordingly,” the official said.

Trump administration officials have repeatedly stressed the military’s role in vaccine distribution. But they have offered few specifics and the military has never been significantly involved in a modern civilian vaccination campaign, experts said. Public health officials worry the lack of clarity about the plan, or the military’s role, could undermine the increasingly tenuous confidence in vaccines and the public health authorities that tout them. That is especially true among underserved African American communities and other communities of color, where trust in medical and political systems is already strained, and where people are most at risk of getting severe illness and dying of covid-19, the disease caused by the virus.

About 7 in 10 Americans say they would get a vaccine to protect against the novel coronavirus if immunizations were free and available to everyone, according to a Washington Post-ABC News poll in late May. But 1 in 7 Americans said they would not get it because they distrust vaccines in general.

Even if one or more vaccines are approved later this year or early next, as many hope, the logistics surrounding their distribution are formidable.

Multiple vaccines may be available at the same time, with different requirements for use and storage. Some may require two shots. Health-care providers and officials will need to make sure that someone getting the first dose of vaccine A gets the appropriate second dose of the same vaccine.

Until recently, federal officials had not spelled out whether they planned to create a new system for distributing coronavirus vaccines, or stick with the existing infrastructure. The traditional vaccination programs, operated by the Centers for Disease Control and Prevention with the states, routinely distribute millions of doses of childhood vaccines every year.

During the 2009 H1N1 influenza pandemic, the CDC scaled up the system to distribute H1N1 vaccine to states. But overly optimistic projections of supply during the second wave of the pandemic in October 2009 resulted in high demand and only limited vaccine doses. By the time an adequate supply of vaccine arrived, demand had fallen.

Whatever systems are ultimately deployed, they will need to “track the supply, manage the allocation equitably around the country, deal with concerns with vaccine that arise, track adverse events, and communicate clearly and transparently,” said Tom Inglesby, director of the Johns Hopkins Center for Health Security, which has released a report about enhancing public trust in coronavirus vaccination.

“There is so much planning to do, and not much time,” he said. “That preparation needs to be happening right now.”

State officials say they also don’t have a clear picture of how much responsibility they will have to shoulder at a time when the federal government has shifted virtually every aspect of the pandemic response to them.

“I feel like there’s an assumption they need to solve all these problems at the federal level, then communicate to the states, when that’s really not what needs to happen,” said Claire Hannan, executive director of the Association of Immunization Managers, which represents directors of public health immunization programs in the states and territories. “We’re not asking for answers. We’re asking to sit down at the table and work them out. … There’s just an assumption that we’ll get some contracts, and ‘yeah, everything will be great.’”

Kristen Ehresmann, director of the infectious-disease epidemiology division at the Minnesota Department of Health, likened the existing infrastructure to a dirt road “that got us to where we need to go.” For the coronavirus vaccine, the government can build on that, “pave the road, make it better,” she said. “But it doesn’t make sense to clear trees and create a new road.”

In its policy memo, the NGA called mass dispensing of a vaccine a “major undertaking.” State officials may need to lease warehouse space and secure freezers or refrigerators for vaccine storage, said Lauren Stienstra, a program director at the governors’ group.

“We would hate, after all the development for a vaccine, to have it expire, or be mishandled somehow, or become wasted as result of lack of planning,” she said.

State officials are also concerned about shortages of needles and vials, she said, noting an uptick in purchase of those items by some states. Given that states competed with each other for personal protective equipment, “our worry going into this scenario is that you will have state-on-state competition for things like syringes,” Stienstra said.

The administration’s plan has become somewhat clearer in recent days. Late last week, CDC outlined a distribution plan in a meeting with immunization groups that uses a model similar to the public health infrastructure used for the H1N1, or swine flu, pandemic, according to participants and the NGA memo.

In that plan, manufacturers would deliver vaccine to a central distributor and states and territories would receive weekly allocations. Places that administer the shots — including private providers and clinics — would send requests for vaccine to state officials, who would prioritize and approve them.

The vaccine would then be sent directly from the central distributor to the receiving location “via contracts arranged by the Defense Logistics Agency,” according to the NGA memo.

Additional supplies of vaccine will be made to “select private partners (likely major retail clinics such as CVS and Walgreens) to expand access,” the memo said.

But the same day as the CDC meeting, senior administration officials described to reporters a process that seemed to give the Defense Department a more prominent role. Vaccine distribution would be a “joint venture” between the Defense Department and CDC that would “combine the best of both agencies,” one senior official said.

The official added: “The DoD is handling all the logistics of getting the vaccines to the right place, at the right time, in the right conditions.” When initial limited doses become available, officials aren’t going to wait for vaccine orders to arrive. “We are going to be pushing the vaccines out to, hopefully, to nursing homes, to seniors who are not ambulatory,” the official said, referring to priority groups at high-risk for covid-19.

Defense would also prepare kits of needles and syringes. He noted that in some cases, when suppliers have said it would take six weeks to get necessary metal to make needles, the government has sent a plane to pick up metal “and have it there in 48 hours.”

In this hybrid model, the CDC, which maintains a vaccine ordering and distribution system for routine immunizations, would be involved in tracking patients after vaccination, the official said. The government is also planning to award additional contracts to help “bring together both the CDC IT capabilities, as well as some new applications that we’re going to need that the CDC never had,” he said.

Jim Blumenstock, who oversees health security for the Association of State and Territorial Health Officials, said the confusion stems from lack of information. What he knows comes from two telephone calls with Warp Speed’s Ostrowski and two webinars with CDC officials.

Information needs to be formally documented and shared so it won’t be misinterpreted or misunderstood, he said.

“We’re assuming at the end of the day, the delineation of lines of authority will be coordinated and transparent and those of us in the field will have a clear understanding of how it’s going to play out,” he said. “Every day we have more confidence, but we still have a ways to go.”

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