DULUTH – Visitors to City of Duluth facilities and some stores and restaurants are once again asked to mask up.

St. Louis County has reported just enough cases — 108 last week — to be considered a "substantial transmission" risk, which means masks should be worn indoors by everyone regardless of vaccination status, according to the Centers for Disease Control and Prevention. Fewer than 100 cases per week would lower the risk and put the county outside of CDC masking guidelines.

"We are as frustrated as anyone, but more than that, we are concerned by this growth in cases," Amy Westbrook, St. Louis County Public Health Division Director, said in a statement. "We all want to put this pandemic behind us, but the highly contagious delta variant is demonstrating why it is so important for people to get vaccinated. There are pockets in St. Louis County that have low vaccination rates that remain concerning."

The City of Duluth announced Tuesday that it would require masks in all city facilities, but it is "not yet putting a mask mandate in place for the city as a whole," said Chief Administrative Officer Noah Schuchman.

Two-thirds of county residents 16 and older have received at least a first dose of the vaccine, but numbers slowed substantially in July.

Westbrook said in an interview the county's messaging will be consistent for the foreseeable future even as cases fluctuate.

"We intend to continue recommending masks for all individuals in indoor spaces until we see a continued trend downward," she said. "Hopefully the situation we're in now will convince more people to get vaccinated."

Businesses are now faced with enforcing the mask guidelines without a state or local mandate. Some, like Whole Foods Co-op, put up "masks required for all" signs over the weekend.

"We're not waiting for a city ordinance," said the grocer's marketing manager, Hillary Heinz. "The Co-op has followed CDC guidance all along."

Heinz said it's confusing to people who are vaccinated and don't understand they can still transmit the virus.

"Some members like it and say it's the only safe place to shop, and some are frustrated and say they will go elsewhere," she said.

At Sara's Table Chester Creek Cafe will also enforce a mask mandate, it announced on social media Tuesday, citing the city's COVID transmission rate.

Mount Royal Market is waiting for a city mandate before reinstating its mask policy, said Steve Schadewald, manager of the eastern Duluth grocery store.

"If the city mandated it, it would certainly make it a lot easier for us," he said. "It's going to be very difficult to get people back in masks."

Schuchman said the city continues to track guidance and information from the CDC, the Minnesota Department of Health, St. Louis County and local hospitals.

"Most of our staff have made the choice to vaccinate and I find it both frustrating and disappointing that we all have to go back to this," Mayor Emily Larson said in a news release. "That said, as hard as it is to take this step back to preserve worker and public health, we now know how effective masks are and how dangerous the delta variant is."

Health officials say vaccines remain the best long-term solution to the pandemic, but masks are now necessary to slow the momentum of the delta variant.

"We want people vaccinated, as that's the most effective tool, but the vaccine doesn't take effect for at least a month — it's not going to stop what's already going around," said Dr. Andrew Thompson, an infectious disease specialist at St. Luke's in Duluth. "So the way to stop transmission now is masking, ventilation and distance. We've got to stop this momentum."

Westbrook said she recognizes the "exhaustion and frustration" among the public as the pandemic enters a new chapter.

"It's going to be challenging, and hopefully the public will respect what local decisions are being made," she said.

Thompson said that even if cases subside over the next week or two, "we should mask for the next few weeks or month until things quiet down again."

"In the hospital, we've gone weeks without seeing a COVID case this summer," he said. "We're hoping that continues."

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