Who gets COVID-19 vaccines first, and when, in Minnesota will hinge on recommendations Tuesday by a federal advisory panel.

Minnesota leaders expect limited initial doses of COVID-19 vaccines — once the U.S. Food and Drug Administration approves them — and the need to ration supplies so they will be most effective at reducing the toll of the pandemic.

"Our vaccinations will be very targeted when the first doses come to Minnesota," said Kris Ehresmann, state infectious disease director. "It won't be a situation where you line up outside a grocery store."

First doses could come in December, with Moderna being the second manufacturer on Monday to apply for FDA approval of its experimental vaccine against COVID-19.

State leaders said the list will largely conform to recommendations by the Advisory Committee on Immunization Practices (ACIP), a federal panel that for years has included Minnesota representatives. Lynn Bahta, an immunization clinical consultant with the Minnesota Department of Health, is a voting member of the committee, which is meeting Tuesday to finalize vaccine distribution guidance for states.

The framework will almost certainly prioritize COVID-19 vaccine for workers in hospitals, clinics and long-term care facilities — perhaps along with residents of long-term care facilities — followed by workers in essential industries and then people with greater risks of severe COVID-19 due to their ages and underlying health conditions.

However, state leaders said the final recommendations will be more complex, and much more challenging than seasonal vaccines or even the rapid distribution of H1N1 vaccine a decade ago.

"They are nothing compared to what we are involved in now," said Patsy Stinchfield, an infectious disease expert with Children's Hospitals and Clinics of Minnesota. She was a voting member of ACIP and now is a liaison to the committee for a trade group of nurse practitioners.

For starters, ACIP is pushing ahead with guidance in the absence of approved vaccines or underlying data indicating their effectiveness.

Moderna reported more than 94% effectiveness in its preliminary trial data, and Pfizer's vaccine has shown similar promise. However, there are multiple vaccines under development — Regions Hospital in St. Paul is part of a clinical trial of an AstraZeneca vaccine, while Allina Health last month launched its trial of the Johnson & Johnson version.

Ehresmann said this rapid planning could result in the first available vaccine going to high-priority groups — senior citizens, for example — only for research to discover that other vaccines work better for them.

"You're not going to sit around and wait. You're going to take advantage of the vaccine when you have it," Ehresmann said, but people need to acknowledge the shortcomings of this somewhat rushed approach.

Whether long-term care residents should be first in line is an open question. Vaccinating all long-term care workers would theoretically create a protective cocoon for residents, for whom the vaccine might not work as well anyway.

However, these mostly older residents have suffered 67% of the 3,593 COVID-19 deaths in Minnesota, making them one of the highest-risk groups in the pandemic.

Bahta said there are practical reasons to vaccinate long-term care workers and residents at the same time.

"Having those vaccinators come in 2, 3, 4, 5 times makes it very difficult," she said. "Feasibility is a big aspect of getting the job done as well."

A Minnesota work group will meet Friday to review the ACIP recommendations and develop a state plan. Logistics are a concern, especially because the initial vaccines will require two doses spread out at different intervals and must be kept in cold storage.

Pfizer's experimental vaccine must be stored at minus 80 degrees Celsius and diluted with saline to be administered. The vaccine as a result will be warehoused in urban centers but still needs to be distributed across Minnesota to people based on their needs, Ehresmann said.

"Certainly, we have to consider the storage and handling requirements," she said, "but we also have to be really careful that we're getting vaccine out equitably. We can't just do what's easy."

Gov. Tim Walz on Monday said mass public distribution of COVID-19 vaccine beyond high-priority groups probably won't occur until late winter or early spring 2021, meaning that Minnesotans need to stick with mask-wearing and social distancing strategies to slow viral transmission.

Complications include sophisticated data tracking to make sure that Minnesotans receive second doses on schedule, and the same types of vaccines they received with the first doses, he said. "Those are things we didn't need to think about in the detail that we do here."

Bahta said she has advocated that ACIP prioritize vaccine for people at greater risk of severe COVID-19 because of underlying health problems or racial or ethnic disparities in the severity of the disease. A review of an initial 6,561 hospitalizations of Minnesotans with COVID-19 found that 77% had at least one underlying health condition, such as obesity, hypertension or diabetes.

Some have argued for a more open-ended approach, or even targeting vaccine at people who are at lower risk of severe COVID-19 but at greater risk due to their youth and mobility of spreading the virus to others at greater risk. Stinchfield said such an approach ultimately falls short of the ethical standards that ACIP developed for getting COVID-19 vaccine to those who need it most.

"It just does not seem ethical to me," she said, "to say we're going to skip over this population of people who are highly impacted."

Minnesota is planning for rapid deployment of vaccines once they have been approved. While other states are taking a week or more to re-examine the clinical trial data before distribution, Ehresmann said Minnesota will bypass that step given its involvement with ACIP and confidence in its safety recommendations.

Ehresmann said unknowns about COVID-19 vaccines include whether they provide long-term protection, or short-term protection like seasonal flu shots. Even if vaccines are as effective as suggested by initial trial results, she said it will take a substantial number of immunizations in Minnesota to halt the pandemic.

"We are looking at the majority of Minnesotans getting vaccinated," she said, "to really feel confident that we can stem the tide from COVID."

Jeremy Olson • 612-673-7744