Resistance to mask-wearing and other efforts to control the spread of the coronavirus has hardened in the final days before the presidential election, demonstrating how the pandemic has been politicized and posing a daunting challenge to the nation’s medical experts.

The refusal to go along with expert health guidance has persisted even in parts of the country that are seeing soaring caseloads and hospitalizations. That was driven home this week when the coordinator of the White House coronavirus task force, Deborah Birx, toured North Dakota, which has had more coronavirus infections per capita than any other state and over the past month has experienced a stunning surge in hospitalizations and deaths.

What Birx witnessed dismayed her.

“Over the last 24 hours, as we were here and we were in your grocery stores and in your restaurants and frankly, even in your hotels, this is the least use of masks that we have seen in retail establishments of any place we have been,” Birx told reporters Monday after participating in a round table with Republican Gov. Doug Burgum, according to the Bismarck Tribune.

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Burgum has endorsed masks but declined to impose a statewide mandate, saying Monday that the decision to wear a face covering is a personal one. He did join Birx in calling for more widespread testing, and on his Twitter account, he cited her view that “more people need to wear masks, socially distance & slow the spread.”

The state reported 889 new infections Tuesday and 15 additional deaths, bringing the cumulative death toll to 481, three-fourths of them in the past eight weeks.

“North Dakota has the highest covid death rate per capita in the world right now,” said Christopher Murray, director of the Institute for Health Metrics and Evaluation at the University of Washington, referring to deaths in the past week. At the same time, he said, data compiled from Facebook indicates that the state has the lowest mask-wearing rate in the United States, between 45 and 49 percent.

It is unusual to see a place where the virus is having such a dire impact making such limited efforts to stop it, he said.

“Usually we see the opposite. Mostly, when things get bad, people get scared, they start getting careful, mask use goes up, mobility goes down,” Murray said.

Hospitals in North Dakota have not run out of capacity, but staffed beds in intensive care units are in dwindling supply. One issue is that many people postponed medical treatment and surgery earlier in the pandemic and are now filling many of those beds, said Tim Blasl, the president of the North Dakota Hospital Association.

Blasl said the resistance to masks has a strong political element.

“We’re a very red state,” he said Tuesday. “What I hear is, ‘The government’s not going to tell me what to do.’ I take the position, ‘Help your neighbor.’ . . . I am concerned about bed capacity in the hospitals here in North Dakota.”

The refusal to wear masks began taking on ideological and political significance this spring as many states and cities issued mask mandates and a loose movement of “never-maskers” coalesced under the banner of personal liberty. The resistance has grown since, fueled by electoral politics, and specifically the back-and-forth zingers about masks between President Trump and Democratic presidential candidate Joe Biden, who frame the pandemic in starkly different terms.

Trump continues to say the United States is “rounding the corner” on the crisis and that “normal life” will soon return. He has mocked Biden and others for their use of masks and even the size of their facial coverings. Biden routinely wears a mask in public appearances and in his television advertisements, and has made Trump’s response to the coronavirus crisis the dominant theme of his campaign.

Caught in this political vise is Birx. She works for Trump but has kept a low profile in recent months as she leads a task force that has been marginalized by the president and a handful of advisers, including Scott Atlas, the Stanford neuroradiologist who has emerged as a presidential favorite. The White House task force did not make Birx available for an interview.

Birx has been active, visiting dozens of states and in many cases persuading governors and other officials to tighten restrictions, increase testing and push people to adhere to expert guidance.

She and other health officials stress that most people remain susceptible to the novel coronavirus, which has killed at least 226,000 people in the United States. The virus is opportunistic and spreads easily among those who do not protect themselves. But also true is that simple measures such as physical distancing, mask-wearing, avoidance of crowds, limiting indoor exposure and good hand hygiene not only can limit the spread, but also are essential to reversing the surges in transmission that have been seen in much of the country over the past month and a half.

Masks function in another way, said William Hanage, an epidemiologist at the Harvard T.H. Chan School of Public Health: “They are one highly visible indicator of how hard people are working” to stop the virus. “It seems in the Dakotas there’s been a disinclination to take the pandemic seriously. Not taking it seriously is literally deadly.”

Yet some people do not appear to accept that.

In South Florida, protesters belonging to a group called Reopen South Florida staged a march Saturday and burned masks. The group formed in April after Gov. Ron DeSantis (R), a strong Trump ally, issued a statewide state-at-home order.

“I don’t see this as a political thing. It’s about freedom,” said one participant, Matt McNabb, a chiropractor in Royal Palm Beach who describes himself as a political independent. “I saw maybe five, six or seven masks burned, maybe for about 30 seconds, then they put it out. It wasn’t as climactic as we were hoping it would be.”

DeSantis has been mask-resistant from the start. He usually, but not always, appears in public without one, including when he attends Trump rallies.

Without a state mandate, local officials have been left on their own, and most major metropolitan areas passed ordinances that are still in place. But DeSantis essentially nullified enforcement of those mandates last month when he said cities cannot fine people for not wearing masks.

Miami-Dade County, for example, issued hundreds of $50 fines for mask violations. But on Sept. 25, DeSantis lifted all restrictions on restaurant capacity and liquor sales. Local governments can keep their mandates, but they cannot collect any fines.

Palm Beach County still has a mask mandate. It was a hard fight, and made Palm Beach a laughingstock after a public meeting where opponents of mask-wearing called the mask mandate “the devil’s law.”

In August, Marion County Sheriff Billy Woods preempted the city of Ocala, which was considering a mandate, and banned masks, even for visitors, at the sheriff’s department.

“In light of the current events, when it comes to the sentiment and/or hatred toward law enforcement in our country today, this is being done to ensure there is clear communication and for identification purposes of any individual walking into a lobby,” Woods said in his order. He later altered it, allowing visitors to be masked.

Infectious-disease experts have cited mixed messaging as a key failure of the United States’ response to the pandemic.

“The inconsistent messaging around the value of masking and reducing our gatherings has now resulted in large swaths of the country that are barely mounting an effort to manage transmission over the winter,” said David Rubin, the director of PolicyLab at Children’s Hospital of Philadelphia.

“Pandemic anger” is the term Michael Osterholm, director of the Center for infectious-disease Research and Policy at University of Minnesota, applies to people who are not merely fatigued by the pandemic but believe it is a hoax.

“The common response you hear in the pandemic anger group is, ‘This is going to go away the day after the election,’ ” Osterholm said.

Hanage lamented the way politics has twisted the response to the pandemic.

“I just wish that people would recognize the virus does not care how you vote. The virus only cares about whether you can transmit it,” he said.

Rozsa reported from West Palm Beach, Fla. Jacqueline Dupree contributed to this report.

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