DULUTH — Duluth Mayor Emily Larson announced a 30-day mask mandate Thursday, as COVID-19 cases fueled by the omicron variant rose in northeastern Minnesota.

Larson declared a local state of emergency, directing face coverings be used in public, indoor spaces for everyone age 5 and older, with some exceptions. The mandate begins at 5 p.m. Jan. 14 and ends at 5 p.m. Feb. 12.

"We know it is inconvenient, we know it is intrusive, but it's still the right thing to do," Larson said at a news conference.

She cited staff shortages at local hospitals — among the area's biggest employers — and their ability to provide timely care to patients as a major reason behind the decision.

The City Council rejected an emergency mandate at its Monday meeting, instead throwing support behind Larson's existing ability to declare an emergency.

Larson was joined Thursday by local health care leaders and public health officials from St. Louis County who pleaded with the public to follow the mandate.

"Masking is one of the most effective tools we have when it comes to preventing the spread of omicron," St. Luke's CEO Dr. Nick Van Deelen said.

The region is expected to soon surpass virus surge levels experienced during 2020's fall peak, he said, noting 162 St. Luke's employees were out Thursday, more than half with COVID-19 breakthrough infections.

Three children already have been hospitalized in January in St. Louis County, said Amy Westbrook, the director of public health for the county. That follows nine with COVID-19 in the previous two months.

Coronavirus rates in the county are skyrocketing, she said, with the majority of cases occurring in the Duluth area.

Essentia Health's new Chief Medical Officer, Dr. Kevin Casey, said hospital staff were working beyond capacity. The mandate will ease some of their strain, he said, and "save lives."

Public places where masks will be required include businesses and churches — any place the public can enter. As did the previous mask mandate that ended last spring, the restrictions don't apply to those actively eating and drinking in restaurants. It also doesn't apply in areas at businesses that are not open to the public, as long as social distancing is maintained, or to law enforcement and first responders if it interferes with safety. It also doesn't apply to child-care settings. Violations could result in warning letters, fines and ultimately, criminal prosecution for trespassing.

The city created posters for businesses to use, alerting customers of the mandate. An email address — mask@duluthmn.gov — is set up for mask compliance issues.

Larson said she knows some will be grateful for the public health mandate and some will be angry, but she asked that people not harass frontline customer service workers, who've already suffered abuse throughout the pandemic.

"If you want to be mad, be mad at me," she said. "People who are reminding you to do your job, your responsibility to follow the law, are just doing theirs."

Grandma's Restaurant Co. President Brian Daugherty said he understands the effort to reduce health care stress and limit the spread of COVID-19 without again shutting down the economy. But masking is another pandemic protocol to add to the list already followed by restaurants, he said, and forces staff to deal with customers who want to debate the efficacy of masks or the legal standing of mandates.

"Hopefully, when the stress is reduced on health care, it can promptly be reduced on our employees, as well," he said.

At Sara's Table Chester Creek Cafe co-owner Carla Blumberg has required mask-wearing at her restaurant throughout the pandemic, and is contemplating a vaccination requirement to eat there, she said.

"I think it's terrible this entire question of mask-wearing and vaccinations was politicized during the Trump era," she said. "We have to be able to do things to get beyond this current state."

Duluth's mandate comes on the heels of mandates in other Minnesota cities, including Minneapolis, St. Paul, Golden Valley and Hopkins.