COVID-19 vaccine boosters for all adults got the green light from federal regulators Friday as part of an effort to slow the spread of the highly contagious delta variant.

The expansion will take effect immediately in Minnesota, Gov. Tim Walz said in a statement.

"Cases are rising, community spread is high, and Minnesotans are moving indoors for the winter as the weather gets colder and the holidays approach," Walz said. "Health officials and researchers agree that booster shots help increase protection against COVID-19."

The move comes as COVID-19 hospitalizations in Minnesota surpassed 1,400 for the first time since last December as the pace of new infections continues to accelerate.

While fully vaccinated individuals are less likely to become seriously ill from COVID-19, they can pass the disease on to others who are more at risk, a prospect that concerns public health officials as families and friends gather over the holiday season.

Boosters were first recommended in late September for the elderly, those with medical conditions that put them at risk for COVID-19 infection and people who work in occupations where public interaction is common.

With approvals Friday from the Food and Drug Administration and the Centers for Disease Control and Prevention, anyone 18 and older becomes eligible for a booster six months after their second Pfizer or Moderna shot. Boosters for everyone who received the one-dose Johnson & Johnson vaccine were approved in October.

"Over time [vaccination] immunity does wane against infection," said Dr. Abinash Virk, an infectious disease specialist at the Mayo Clinic. "Boosters have increased the antibody response significantly after the third dose much higher than even the second dose. Therefore we know there is going to be increased protection."

The decision to open up eligibility for boosters was expected. Minnesota health officials said earlier this week that they would approve boosters for all adults, as other states have already done, if federal regulators did not take action first.

"Boosters are an important part of keeping protection against COVID-19 high in adults and helping to mitigate some of the intense COVID-19 spread we are seeing right now, which is extremely important given our tight hospital capacity," Minnesota Health Commissioner Jan Malcolm said.

Minnesota's hospitals reported that they were caring for 1,414 patients with complications from COVID-19, including 340 in intensive care.

Only 2% of adult beds were not occupied and 56 hospitals reported that their adult ICU beds were at capacity.

Pediatric ICU bed space also was tight at 92% capacity as of Thursday.

The influx of COVID-19 patients comes as Minnesota on Friday reported another 5,162new infections and 30 additional deaths.

Minnesota's case surge shows no sign of slowing down. The testing positivity rate has risen to 10.8% at a time when the number of Minnesotans getting tested is increasing.

"We are still very, very concerned about our numbers," state infectious disease director Kris Ehresmann said in an online presentation to the Minnesota Academy of Family Physicians on Thursday.

Case counts have not reached the levels seen last fall, when hospitals saw a record 1,864 COVID-19 patients in late November, but a shortage of health care workers this fall has put new pressures on the hospital system.

"The impact is just about as great on our health care system because capacity is so much more constrained," Ehresmann said. "COVID taxes the system and then other legitimate and necessary situations that require ICU care are put in a tough place."

About 846,000 Minnesotans, or 26.1% of fully vaccinated adults, have received their booster, according to the CDC.

MDH informed vaccine providers Tuesday that they should prepare for expanded eligibility, including modifying scheduling systems so that appointments could be offered quickly after the authorization. COVID-19 vaccine inventory levels are high, according to state officials.

Under a previous decision by federal officials, people can choose which vaccine brand they want for the booster.

Data presented to the CDC's Advisory Committee on Immunization Practices on Friday showed that most stuck with the same vaccine with one exception.

Among 381,000 people who initially received the Pfizer vaccine, 99% got Pfizer as a booster. Among 305,000 Moderna recipients, the repeat rate was 95%.

But for 40,000 Johnson & Johnson vaccine recipients, only 16% used that brand as a booster.

Since the pandemic began, 871,203 COVID-19 infections have been detected in Minnesota residents, including 9,486 reinfections.

A total of 9,155 Minnesotans have died of COVID-19 complications. Among the 30 deaths reported Friday, 13 were long-term care residents.

Testing laboratories reported 55,526 COVID-19 test results to the state health agency on Thursday. On average, 43,000 test results are being reported daily compared with 34,000 at the beginning of November.

State officials also announced Friday that they have entered into master contracts with 11 testing laboratories to make it easier for state and local governments, including school districts, to select labs to process tests.