More than 84,000 people as of Tuesday morning had received first shots of COVID-19 vaccine in Minnesota, where extra doses in vials have stretched the limited initial supply.

HealthPartners reported squeezing six doses out of almost all five-dose vials of Pfizer COVID-19 vaccine, meaning that its initial allotment of 10,000 doses by week's end could provide as many as 12,000 shots for doctors, nurses and other providers.

"It's possible we will have a larger number of vaccinations than what our allocation would otherwise be on paper," said Dr. Mark Sannes, who is leading the COVID-19 response for the Bloomington-based health care system. "Our goal is to give all that we get."

The Minnesota Department of Health on Tuesday reported that 80,857 people had received first doses of the two-dose COVID-19 vaccines made by Pfizer and Moderna. The state has received 297,350 doses through last week, and expects another nearly 66,000 doses this week — based on guidance that each Pfizer vial contains enough vaccine for five injections and each Moderna vial contains enough for 10.

The U.S. Food and Drug Administration on Dec. 16 issued a tweet advising the use of extra doses after health systems received their first Pfizer vials and found more vaccine than expected. The caveat is that vaccine can't be mixed from multiple leftover vials to create extra doses.

Health care providers said they were grateful for the extra doses of vaccine against the novel coronavirus that causes COVID-19. The pandemic has now caused 5,461 deaths in Minnesota and 425,261 diagnosed infections, including 18 deaths and 1,612 infections reported on Tuesday.

Limited initial vaccine supplies have been rationed for health care workers who are at risk of viral exposure and long-term care residents who are at greater risk of severe COVID-19 illness due to their age and underlying health problems.

Minnesota has enough doses in hand to provide first injections to health care providers who are at greatest risk, mostly those who work in COVID-19 units or emergency departments, said Kris Ehresmann, state infectious disease director. The state is on track to provide first doses to all health care workers and long-term care residents by month's end, she added.

Ehresmann said it was remarkable that multiple vaccines have been developed, approved and delivered against a novel coronavirus that was identified only a year ago. She also disagreed with criticism of a slow rollout in Minnesota, noting that the state has taken a deliberate approach of educating providers on the handling of the complex vaccine and still ranks 16th per capita for the number of shots provided.

"It's time that we celebrate how far we've come in a very short amount of time," she said.

Sannes said vaccine side effects have been uncommon and mild. HealthPartners as of Tuesday had provided 9,148 shots, and is now on pace to conduct almost as many vaccinations as doses received each week, he added.

Second doses are starting to arrive in Minnesota as well for injections three to four weeks after the first shots. The Minneapolis VA Medical Center through Monday had reported providing 3,125 first doses to workers and veterans, and 102 second doses.

COVID-19 vaccinations in Minnesota by federal agencies such as the VA and Indian Health Service are in addition to the daily totals reported by the state Health Department.

Formal state guidance is being updated this week regarding the use of extra doses of vaccine in multidose vials. Some providers have found they can gain an 11th dose out of 10-dose Moderna vials as well.

Mayo Clinic is using extra doses to conserve whole vials and keep them in frozen storage for emergencies, said Dr. Abinash Virk, a Mayo infectious disease specialist. The extras could be invaluable if there is any delay in shipments of second doses.

"We need to account for some day-to-day ups and downs that could happen with vaccine supply," she said.

Syringe size makes a difference in whether providers can conserve enough vaccine to produce an extra dose from vials, Virk said. Earlier shipments came with smaller syringes but more recent ones have come with larger syringes that don't leave as much vaccine behind, she said.

Mayo is still getting six doses out of 85% of Pfizer vials, but any loss of capacity is disappointing, Virk said. Use of larger syringes Monday and Tuesday resulted in 28 vials that only produced the expected five doses.

"That's basically 28 people we could have vaccinated but didn't, purely because of the syringe issues," she said.

Pandemic indicators have continued to improve in Minnesota, following a COVID-19 wave that emerged in the Upper Midwest this fall and then spread to the rest of the country. The state on Tuesday reported that 155 people with COVID-19 were admitted to intensive care beds in Minnesota hospitals, the lowest number since late October and a dramatic decline from a peak of 399 patients on Dec. 1.

But state health officials remained cautious and concerned that gatherings over the holidays could have fueled an increase in viral transmission. The positivity rate of COVID-19 diagnostic testing had briefly dropped on Dec. 24 below the state warning threshold of 5%, but jumped up to 6.3% on Dec. 27.

A similar uptick occurred around Thanksgiving. Both increases could have been due to decreased testing activity during those holiday weeks, but might also reflect increased viral transmission.

Health officials urged people to continue to wear masks in public, practice social distancing and avoid large gatherings. Indoor service remains closed at bars and restaurants through Jan. 10, but Gov. Tim Walz is scheduled Wednesday to announce a loosening of those restrictions.

The Minnesota COVID-19 Vaccine Allocation Advisory Group is seeking public comment through Thursday and is scheduled to meet Monday to discuss the vaccination of the second priority group: people 75 and older, and workers such as teachers, police officers and power plant employees in front-line essential industries.