COVID-19 hospitalizations in Minnesota rose back above 300 for the first time since March 10, but the virus isn't producing the same severity of illness as prior pandemic waves.

Among 305 COVID-19 hospitalizations on Monday, 22 required intensive care — a 7% rate that is the lowest in the two-plus years of the pandemic.

"[The coronavirus is] more contagious than recent months, but severity of illness remains low," said Dr. Mark Sannes, an infectious disease expert with HealthPartners, which over the past week has reported zero ICU admissions because of COVID-19 at Regions Hospital in St. Paul or any of its other seven hospitals in Minnesota and western Wisconsin.

Health officials remain concerned that continued growth in infections could ultimately increase severe COVID-19 cases and put pressure on hospitals again as they head into the typically busy summer season for traumatic injuries. The Minnesota Department of Health on Tuesday reported another 2,505 infections, which includes all cases identified over the weekend.

The seven-day average of new infections has tripled over the past month to more than 1,200 per day, even though the state total doesn't include at-home tests, which aren't reported publicly. Sampling of sewage from 40 Minnesota wastewater treatment plants through April 27 showed increasing signs of the coronavirus in all seven of the state's surveillance regions.

HealthPartners is reporting 3 to 8% test positivity for COVID-19 among patients at its clinics and hospitals who have no symptoms. The norm among asymptomatic patients during the pandemic has been less than 2%, Sannes said.

The fast-spreading BA.2 subvariant of the coronavirus has produced most of the new cases in Minnesota.

That subvariant caused a higher rate of severe COVID-19 cases and hospitalizations in Europe this spring than it has so far in Minnesota. Health authorities suspect that reflects vaccination progress as well as the large number of Minnesotans who gained immunity from infection during the winter's omicron pandemic wave.

The Centers for Disease Control and Prevention estimates 61% of Minnesotans have been infected with the coronavirus over the past year or two, based on the prevalence of COVID-19 antibodies found in blood samples from recent medical tests.

Minnesota reported one COVID-19 death Tuesday, bringing the state's total to 12,512, and has averaged two per day over the past week.

The 63 COVID-19 deaths preliminarily reported for April in Minnesota are the lowest monthly total since July and well below the 1,080 in December during the peak of the severe delta wave.

Fully vaccinated people are making up more of Minnesota's COVID-19 deaths, including five of six deaths reported in the final week of March, according to the latest state breakthrough data released Monday. Even so, the breakthrough data has shown the vaccine to be protective. Fully vaccinated people make up 79% of Minnesota's adult population but 41% of the COVID-19 deaths since April 2021.

The state breakthrough data has limited utility because it doesn't differentiate cases in vaccinated people by whether they received recommended booster doses. People fully vaccinated in early 2021 are presumed to have little immunity left without boosters.

State health officials said they plan to update the breakthrough data and identify COVID-19 cases by booster status in the coming weeks.