Hundreds of residents and staff of Minnesota nursing homes began to get vaccinated Monday for the novel coronavirus — a critical turning point in the state's battle to protect people who are particularly vulnerable to the deadly disease.

Early Monday, teams of pharmacy workers with CVS Health and Walgreens fanned out to dozens of nursing homes across the state, which have been especially hard hit by the virus, and began administering initial shots of the Moderna vaccine. The plan is to vaccinate everyone who lives or works at Minnesota's 2,100 long-term care facilities, including assisted-living homes, by the end of January, dependent on vaccine supply, state officials said.

Elderly residents and employees of senior care facilities have been given priority for the vaccines because they have been shown to be especially at risk of being exposed to the virus. Large nursing homes, in particular, have been the sites of fast-moving outbreaks that have sickened or killed hundreds of seniors and forced many facilities to impose strict lockdowns that kept residents from seeing loved ones for months at a time, exacerbating health problems. So far, 65% of the 5,160 deaths from COVID-19 in Minnesota have occurred in long-term care communities, state records show.

The vaccines are arriving at a precarious time for senior care providers still reeling from a frightening resurgence of COVID-19 infections during the fall. A rash of new outbreaks since September has strained facilities that were already short of staff and has forced a growing number of facilities to reach out to the state for emergency assistance, in a rerun of the pandemic's harrowing early months. Infections have abated in recent weeks, but the virus is still raging in these communities: Some 87% of Minnesota's nursing homes and 55% of assisted-living facilities still had active outbreaks of the virus as of Dec. 21, according to state Department of Health data.

"This is a really big deal. It gives us hope and literally will save lives," said Patti Cullen, president and chief executive of Care Providers of Minnesota, a long-term care industry group. "I am also telling folks to be patient — they need two doses of vaccines plus two weeks after for full impact, and we will not be reopening to full visitation until the vaccine is more widely distributed."

State health officials said that all 369 skilled-nursing facilities are expected to administer vaccines to staff and residents over the next few weeks. The agency said that the state's 1,700 assisted-living facilities, which house more than twice as many people as nursing homes, are expected to begin vaccinations in mid- to late January.

The large pharmacy chains spent months planning the vaccination rollout and are doing it in phases. The initial focus is on skilled-nursing homes because they house sicker and more vulnerable patients. The effort's logistics differ by facility, but residents are typically brought out of their rooms and receive the shots in communal areas while staying socially distanced from others. Elderly residents who are too frail or sick to move have been receiving the injections in their rooms.

A spokeswoman at CVS Health said the company's pharmacists planned to vaccinate residents and workers at nearly 600 nursing homes and assisted-living facilities over the next three months. Both the Pfizer and Moderna vaccines require two doses, spread three to four weeks apart, which is why the process will take so long. All told, the vaccinations by CVS will reach 63,000 residents and staff across Minnesota.

Astrid Anderson, 91, a retired schoolteacher, was elated after receiving the vaccine on Monday afternoon in her room at a St. Paul senior home. She described the shot as "virtually painless," and expressed her hope that the virus would be contained enough by spring that she would be allowed to visit her family. Like many seniors, Anderson has been unable to leave her facility, except for medical appointments, since the pandemic began nine months ago. Even small outings, like going out to lunch with relatives, have been impossible, and group activities in her senior home have been canceled since March.

"My first thought was 'hooray!' " Anderson said from her room a few hours after she was vaccinated. "I've been cooped-up here since March and I can't wait to get out."

Now, Anderson is holding out hope that, by summer, she will be able to leave the facility and enjoy a big dinner at home with her six children and grandchildren who live in Minnesota. "This [vaccine] will one day give us all a little more freedom to see the people we really care about," she said. "Once enough people get this, things are going to change and the dark days will end."

Still, nursing home administrators and industry representatives caution that it could be several more months, or even longer, before life at senior homes will return to normal and they will be able to lift visitor restrictions. That's because the infection rate is still alarmingly high in many of the communities that surround senior homes; and the vaccines may not be available to the broader public until late spring, depending on the pace of vaccine production and government approvals. State and federal guidelines also limit when facilities can open their doors based on infection rates in the community and whether they have active cases of the virus in their buildings.

"In general, the process we go through every day is not going to change overnight because we have the vaccine," said Amanda Johnson, a nurse and vice president of clinical operations at Tealwood Senior Living, a Bloomington-based company that operates 30 senior homes in Minnesota. "We can protect those who are most vulnerable, but we also have to find a way to encourage everyone outside these facilities to protect those folks, too."