Minnesota's rate of new coronavirus infections has been worst in the nation over the past seven days, according to the latest federal data, and has brought the state's hospitals closer to capacity.

State health leaders encouraged Minnesotans to protect themselves with mask-wearing and social distancing measures that Gov. Tim Walz no longer has authority to impose. Recent gains in COVID-19 booster and pediatric vaccinations should help, but won't have an immediate impact because the shots take days to coax immune responses.

"We are in the middle of a COVID blizzard right now in Minnesota, so that's a challenge," state infectious disease director Kris Ehresmann said. "If we could get people to consider implementing the layered mitigation, if we could get more people vaccinated and if people continue to seek out boosters, that will make a difference."

COVID-19 hospitalizations increased to 1,282 on Friday, including 311 patients in intensive care. More than 95% of available inpatient hospital beds were filled with COVID and non-COVID patients, resulting in backups in emergency departments across Minnesota.

St. Cloud-based CentraCare encouraged people to take protective measures and licensed health care professionals to return to work and address a shortage that has worsened since earlier pandemic waves.

"We couldn't have made it through the early pandemic without our community's support, and we ask for your help again," said Dr. Ken Holmen, CentraCare's chief executive.

The state on Monday reported another 5,266 coronavirus infections and a 9.7% positivity rate of COVID-19 diagnostic testing that brings Minnesota close to its 10% high-risk threshold for widespread viral transmission for the first time since December.

Breakthrough infections in fully vaccinated Minnesotans remain a component of the latest wave, because early recipients last winter are encountering waning immunity and needing booster doses. The state on Monday reported another 7,784 breakthrough infections and a total of 72,629. COVID-19 deaths in fully vaccinated Minnesotans increased to 519.

Vaccination progress continued in Minnesota, which ranked second among states for its rate of booster doses among people 18 and older, according to the Centers for Disease Control and Prevention. Boosters are recommended for all recipients of the Johnson & Johnson vaccine and for recipients of the other vaccines who are seniors or younger adults with health problems or jobs that put them at risk for infection.

Minnesota's first-dose vaccination rate among people 12 and older is almost 78%, according to the CDC, while the state reported that more than 30,000 children 5-11 have taken advantage of the new pediatric doses.

Unvaccinated people make up the majority of COVID-19 cases, hospitalizations and deaths in Minnesota even though they make up the minority of the state population. The trend is shifting, though, with the most recent breakthrough data showing 47 COVID-19 deaths of fully vaccinated Minnesotans in the week of Oct. 10-16 compared with 44 in unvaccinated people. Health officials said the early vaccine recipients include the elderly and people at greatest risk of COVID-19, so waning immunity makes them vulnerable again.

Hospitalizations remain more common among the unvaccinated, who are more likely to need intensive care and ventilators for treatment as well. Unvaccinated people made up 70% of the 709 people with COVID-19 who were newly admitted to hospitals Oct. 10-16.

Minnesota has the nation's highest rate of new coronavirus infections, but the "whole Midwest is lighting up," said Michael Osterholm, director of the University of Minnesota's Center for Infectious Disease Research and Policy. Masks can help but too often they aren't worn properly, so Osterholm said continued vaccination is the key strategy.

"Vaccine has an impact on how big that surge is," he said. "It doesn't necessarily have any impact on when it starts or when it stops, but the size of the surge is completely related to vaccine levels."

Studies have been fairly convincing that boosters increase protection and that vaccination even after previous infection makes a difference, he added. "If you have had an infection, that really is in a sense like a dose of vaccine, but you want to get that additional [protection]. That's really important."