Minnesota has identified seven coronavirus infections involving the omicron strain, and only two were linked to one another or out-of-state travel, meaning the variant is spreading in the state.

Health officials are concerned that omicron could exacerbate the current pandemic wave in Minnesota, where the state has reported 975,447 coronavirus infections and 10,057 COVID-19 deaths since the virus first took hold here. Those totals include 3,805 infections and 39 deaths reported Thursday amid the latest wave, which is fueled by the fast-spreading delta variant.

Reports globally suggest that COVID-19 vaccines might be less protective against omicron infections, but they still reduce risks of hospitalization and death, said Kris Ehresmann, state infectious disease director. She urged more vaccinations and boosters but also encouraged mask-wearing and other protective measures, especially given travel and gatherings over the holidays.

"When we consider the introduction of omicron into our community — we have cases in Minnesota that clearly were the result of community spread — it's all that much more important ... to be attentive to mitigation measures like masking indoors," she said.

Minnesota has increased genomic sequencing this fall to 3,000 or more samples from positive COVID-19 cases per week to search for variants and track shifts in pandemic activity. Key features of initial diagnostic tests allowed public and private labs in Minnesota to select specimens that were suspected of being omicron. The state was the second in the country last month to report an omicron infection in a 30-year-old Minneapolis man who had traveled to New York for a large anime convention.

Six of the omicron infections were identified in people in the Twin Cities, while one occurred in someone from greater Minnesota. The lack of connectivity between the infections means the virus is presumed to be spreading within the state now.

Omicron was labeled a variant of concern after it was discovered in November in South Africa, because it rapidly replaced delta as a dominant variant there and showed some potential to evade immunity obtained from vaccination or prior infections. Initial cases were mild, though, raising the question of whether more rapid spread would be a problem if omicron produced a lower rate of severe illnesses and hospitalizations.

Minnesota's hospitals remained pressed on Wednesday by the current pandemic wave, though the number of COVID-19 patients has declined from a recent high of 1,678 on Dec. 9 to 1,583 on Wednesday. The latest total includes 369 people receiving intensive care, and they combined with non-COVID patients to fill all but 17 staffed adult ICU beds in the state.

"I listened to a charge nurse say, 'The only way we will have an empty bed today is if someone dies,'" said Dr. Peter Bornstein, an infectious disease specialist whose group staffs four East Metro hospitals. "That's just incredibly depressing."

Gov. Tim Walz announced that federal medical support teams would remain at HCMC in Minneapolis and St. Cloud Hospital through late January to address staffing shortages and patient demand.

Minnesota's seven-day rate of new infections has declined every day since Dec. 6, according to the Centers for Disease Control and Prevention. The state has the 14th-highest rate of infections after having the worst rate for much of November. The data suggest a peak in the latest wave, and Minnesota officials are hopeful that an increase in new vaccinations and booster doses have played a role in reversing the trend.

However, state Health Commissioner Jan Malcolm said she wasn't ready to declare that Minnesota was on the downside of the latest wave: "We've seen some downturns before that just didn't hold."

Malcolm and other state officials gathered at Children's Hospital in Minneapolis on Thursday to commend the progress in COVID-19 vaccinations one year after they became available.

CDC data show that more than 3.6 million Minnesotans have been fully vaccinated, though that leaves about 1 million more eligible residents 5 and older who have yet to receive shots. Minnesota also ranks second among states in fully vaccinated people — particularly seniors — who have received booster doses to address the waning immunity that appears to occur six months after initial shots.

"That's good protection for some of the most vulnerable folks that we have seen suffering disproportionately from severe illness, hospitalization and death," Malcolm said.

While breakthrough infections in fully vaccinated Minnesotans have increased this fall because of that fading immunity, hospital leaders report that unvaccinated people make up most of their severe cases. Allina Health on Tuesday reported that 331 of 439 COVID-19 patients admitted to its hospitals were unvaccinated. Among 89 patients in intensive care, 77 were unvaccinated.

State health officials also have reported an uptick in deaths of younger unvaccinated adults, even though seniors make up 85% of the total COVID-19 deaths. Thursday's newly reported deaths included four people age 30 to 39. The state has now reported 137 COVID-19 deaths in people younger than 40.