The coronavirus is surging back into Minnesota's senior homes, with facilities running desperately short of the one resource they cannot go without — staff.

Across the state, a second wave of coronavirus cases is raging through nursing homes and assisted-living facilities that escaped the first wave of outbreaks this spring, once again threatening older adults who are most at risk of dying from COVID-19, the respiratory disease caused by the virus.

Nearly 11,000 residents have tested positive for the new coronavirus, with one out of five dying from COVID-19 complications.

This time, the virus is infiltrating many facilities in rural communities where staffing shortages are more severe and residents have fewer options. Facilities in counties such as Aitkin and Mille Lacs that largely avoided the virus during the spring are now reporting explosive new outbreaks.

An alarming 90% of Minnesota's nursing homes and 58% of the state's assisted-living facilities have active outbreaks of the virus, according to new data from the Minnesota Department of Health. That includes more than 70 senior care homes that didn't have any COVID-19 infected residents one month ago.

The spike in cases is causing a feared rerun of the pandemic's harrowing early months, when mounting deaths forced facilities to shut their doors to families and to scramble to find resources. After ebbing over the summer, coronavirus deaths in Minnesota's nursing homes and assisted-living settings have surged 49% since late September and are now approaching levels not seen since May. Overall, long-term care facilities have been tied to 2,244 deaths since the start of the pandemic, representing 68% of all COVID-19 deaths in the state.

"This is really our worst fear imaginable," said Amanda Johnson, a nurse and vice president of clinical operations at Tealwood Senior Living, a Bloomington-based company that operates 30 senior facilities in Minnesota.

The development is a discouraging result of uncontrolled community transmission of the virus in many parts of the state, as colder weather pushes more people indoors for gatherings with friends and family.

Despite stringent lockdown measures and more expansive testing, the rapid rate of community spread has allowed the highly contagious virus to creep back into facilities through employees who are not showing virus symptoms, according to long-term care administrators.

In a sign of how stressed the senior care industry has become, state Health Commissioner Jan Malcolm said Tuesday that 47 long-term care facilities are in "a crisis staffing situation" and are receiving active support from the state, including help from federal health nurses and recruitment for volunteers.

The administration of Gov. Tim Walz is also taking the unusual step of e-mailing all state employees, asking them to consider volunteering for two-week stints in long-term care facilities facing critical staffing shortages, particularly in greater Minnesota. No prior experience is required, and costs associated with travel and temporary housing would be covered by the state, according to the e-mail, which was sent to the heads of all state agencies.

"We're trying to turn over every stone, so to speak, to think about ways to support the staffing needs across the health care continuum, particularly in long-term care," Malcolm said.

For now, the virus is spreading with ferocious speed throughout dozens of smaller senior communities from the Iowa border to the Red Lake Indian Reservation in northern Minnesota, where staffing has long been a problem.

At Franklin Rehabilitation and Healthcare Center, a 40-bed nursing home in Renville County in south-central Minnesota, 31 residents and 17 staff have been infected since early November.

As of Tuesday, six residents had died, a spokesman for the home said. So many staff were sickened or exposed to the virus that, at one point, the facility's social worker, dietary manager, activities director and housekeeper had to perform tasks normally reserved for trained clinicians.

"This is real, and it doesn't matter what you believe," said Josh Domeier, the nursing home administrator, in a recent video update posted on Facebook. "I am watching residents who were just fine yesterday who are tanking today, and my head has been thrown and spun in hundreds of directions."

Minnesota health officials said the chief culprit is the sheer amount of coronavirus cases that surround senior care communities, even in rural areas. Young people who visit bars and restaurants contract the virus and spread it to health care workers, who unknowingly bring it into senior homes.

Rampant community transmission "creates a double threat of more opportunities for unwitting introduction of the virus into facilities," said state infectious disease director Kris Ehresmann. "At the same time, more staff are getting sick or being quarantined, which puts a greater burden on the existing staff and makes it harder to maintain infection prevention."

At some places, the pool of workers has become so dangerously depleted that facilities have reached out to the Minnesota National Guard as a last resort.

The National Guard has dispatched nearly 100 medical professionals, organized in small teams, to seven long-term care facilities with active outbreaks. Last week, tribal leaders with the Red Lake Nation reached out to Walz to request help from the National Guard after 18 residents and 14 staff became sickened with the virus at the Jourdain/Perpich Extended Care Center, a 47-bed facility on the reservation.

"Hopefully our nurses will be able to get some rest soon with all the help that is being sent," Red Lake Tribal Chairman Darrell Seki Sr. said in an statement posted online. "I want to remind all tribal members to be safe ... to protect yourself, your children and your relatives."

Many nursing homes are testing their residents and staff twice a week, which enables them to quarantine infected residents much sooner than they did during the pandemic's early months. Even so, many of the newer outbreaks are occurring in smaller buildings where sickened residents may be harder to isolate. Unlike larger complexes in the Twin Cities metro area, senior homes in small towns are often single-floor structures with little or no space to create special wings or floors for infected residents.

"Even with all the precautions and all the testing, the virus is so pervasive in the community that you still miss people," said Johnson of Tealwood Senior Living. "They slip through the small windows between tests."

Dustin Lee, chief executive of Prairie Senior Cottages, which operates seven assisted-living and memory care homes statewide, including several with small outbreaks, likened efforts to contain the virus and to keep it out of senior homes to a military operation.

"This is worse than war. War has a beginning and an end," said Lee, who spent 23 years in the Army and Air Force Reserves and served in Iraq. "In a war, you can usually see or hear the bullets and the enemy. This enemy is invisible, highly contagious and lethal to those in society who are most vulnerable."

The resurgence of cases — coming just before the holidays — has forced many facilities to reimpose strict lockdown measures that were lifted during the summer.

Indoor visits and group activities have been barred at facilities with active outbreaks, which means many residents will be confined to their rooms on Thanksgiving Day, unable to hug their relatives or enjoy a family meal.

Kathy Meinhardt is anxiously debating whether to bring her 92-year-old mother to her home for the holidays after learning Monday of a growing outbreak at her mother's assisted-living facility in New Ulm. At least 10 residents and three staff have been sickened at the facility, Orchard Hill Senior Living, and Meinhardt has become concerned that the facility could run out of space to quarantine sickened residents.

"I am very, very worried," said Meinhardt, who lives in Bloomington. "I don't know the magic number, but if infections keep going up then we may have to call it an early Christmas and bring Mom home until this virus is brought under control."