Minneapolis and St. Paul renewed mask mandates in city facilities on Tuesday and encouraged people in the Twin Cities, regardless of their vaccination status, to wear them indoors in response to a variant-fueled wave of COVID-19.

While Minnesota has the ninth-lowest rate of new viral infections among states, according to a weekly federal profile report released Tuesday, the severe surges elsewhere in the U.S. and the recent local uptick prompted a wave of preparations. The state on Tuesday reported a 4% positivity rate of COVID-19 diagnostic testing — up from a low of 1.1% a month ago — and case and hospitalization rates that are back above caution thresholds.

"This pandemic is far from over," St. Paul Mayor Melvin Carter said in a statement. "These measures will help protect us as we continue our work to get our entire community vaccinated."

Hennepin and Ramsey counties reinstated their mask mandates in county facilities as well Tuesday, a day after Target, Cub Foods and other retailers required masks for employees and encouraged them for customers in areas with high coronavirus transmission levels.

State Health Commissioner Jan Malcolm on Monday said a "very opportunistic" delta variant is fueling the uptick — with roughly a third of eligible Minnesotans 12 and older having received no vaccine against COVID-19. Viral loads have tended to be much higher in people infected with the delta variant — even in rare breakthrough cases involving vaccinated people — making them more likely to spread the coronavirus.

"Heading back up in these case counts is a direction no one wanted to go," Malcolm said.

Several local mask requirements followed a recommendation by the Centers for Disease Control and Prevention last week for people to wear them in K-12 schools and in counties with high or substantial levels of viral transmission.

That county number has been fluid in Minnesota, but it reached 47 on Tuesday — with all metro counties in the substantial viral transmission range and eight other counties including Freeborn and Nobles in the high range.

Transmission levels at the moment don't correlate entirely to vaccination levels — with urban Hennepin County having substantial transmission despite a first-dose vaccination rate of 77% in eligible people 12 and older, and rural Clearwater County having moderate transmission despite the state's lowest vaccination rate of 41%.

Ramsey County leaders had preliminary discussions of a vaccine mandate for workers on Tuesday, one day after the Fairview and Allina health systems announced such requirements with some exceptions for their workers.

The University of St. Thomas also announced a vaccine requirement for students and staff before they return to campus this fall — joining about 600 colleges nationally, including several local institutions.

St. Thomas opted to require vaccines — and masks only for unvaccinated students — with the hope it can push its 78.4% COVID-19 immunization rate higher and preserve in-person learning, said Karen Lange, St. Thomas' vice president for student affairs. The rising impact of the delta variant also was a concern.

"We just thought this was stronger to have the vaccination requirement," which offers the same exceptions that exist for other required vaccines, she said.

The Minnesota Department of Health on Tuesday reported 1,667 more diagnosed infections, accounting for cases identified over the weekend, and four COVID-19 deaths. The additions raise Minnesota's pandemic totals to 614,990 known infections and 7,678 deaths.

The state on Tuesday also reported 248 COVID-19 hospitalizations in Minnesota, up from 90 three weeks ago.

Malcolm said studies have shown that all three COVID-19 vaccines substantially reduce the risk of severe illness and death, and she hoped fatalities would remain lower in this latest wave when compared with others as a result.

Vaccination levels remain below state targets, but the latest state data showed a gradual increase in doses administered — from 36,033 in the week beginning July 11 to 41,007 in the week beginning July 18 to 45,112 in the week beginning July 25.

The state on Tuesday reached a first-dose vaccination rate of 69% in people 16 and older.

The state had initially sought to reach 70% in that population by July 1, but it fell short amid slowdowns in vaccination activity.

Vaccine wastage increased as health officials risked opening and thawing more multidose vials in order to make them accessible to people when they were ready to receive their shots.

The latest state data on Thursday showed more than 5.9 million doses administered and 64,651 doses wasted. Half of the waste was due to the opening of vials but then not providing all the doses before they expired.

New vaccine recipients will receive $100 under a new state incentive program, with the registration site for the reward opening on Wednesday.

"Get vaccinated," urged Minneapolis Mayor Jacob Frey in his masking announcement on Tuesday. "Getting the vaccine will help protect you and your neighbors from a deadly virus, and it is the single most important action we can all take to curb the need for further restrictions."

Staff writer Shannon Prather contributed to this report.