Being mostly rural and far from the coasts didn't protect North Dakota and South Dakota from Covid-19.
After a spring and a summer of flimsy or nonexistent public health measures, politicization of the pandemic and rampant misinformation, the states were tinderboxes.
Then came the Sturgis Motorcycle Rally in August. The gathering of nearly half a million people in a small town in western South Dakota sent case numbers and deaths soaring in both states.
By November, North Dakota had the highest coronavirus infection rate per capita in the world. In South Dakota, the death rate reached a global high.
Unlike states that had soaring case counts early in the pandemic, neither North Dakota nor South Dakota ever issued stay-at-home orders. Mask mandates, if they came, came late. Yet numbers in both states have come down significantly since the late fall peak, and the Dakotas have emerged as national leaders in vaccine distribution — both are closing in on 5 percent of their total populations' being fully vaccinated, putting them in the top five in the country.
But beneath the surface, experts fear that the success could be tenuous: Misinformation, a false sense of security and the politicization of infection prevention measures are setting the stage for a possible second surge.
The pandemic got personal
By Halloween, Covid-19 had been ripping through South Dakota for two months. But when Nick Brown, 29, drove through downtown Brookings — the state's fourth-largest city, near the Minnesota border — he passed a string of bars that hosted maskless crowds. At one bar, a local rock band played for a packed house.
Brown, who was a doctoral student in mathematics at South Dakota State University at the time, said he was diligent about wearing masks and avoiding crowds, but he noted that the topic had become political and that not everyone followed public health recommendations.
The situation was nearly identical in the state's northern neighbor.
Dr. Paul Carson, director of the North Dakota State University Center for Immunization Research and Education, said that as he and his wife traveled across the state in the summer, masks were sparse and physical distancing was almost nonexistent, particularly the farther west they went. Adherence to public health measures was slightly better in eastern hubs, including Fargo, which had implemented mask guidance in the absence of a statewide order.
Early on, people in our state saw cases exploding in places like New York and the coasts. It seemed like it was a problem for large, urban metropolitan centers, not us.
"Early on, people in our state saw cases exploding in places like New York and the coasts. It seemed like it was a problem for large, urban metropolitan centers, not us," he said.
That had changed by mid-November, when "it became unavoidable to not know someone who was in the hospital or who had died of Covid-19," he said. "People felt it personally. It became clear that our hospitals were overrun."
That undeniable evidence, Carson said, helped motivate people to make the changes that eventually turned the tide. "It became hard to say that the epidemic is being overblown, that it's no worse than the flu, and this influenced people to change their behavior." Mask-wearing and social distancing, he said, increased.
Finally, on Nov. 13, North Dakota Gov. Doug Burgum issued a statewide mask mandate and restricted capacity in bars and restaurants.
Such an order never came in South Dakota, one of the few states to issue no restrictions to curb the spread of the coronavirus.
South Dakota Health Secretary Kim Malsam-Rysdon didn't address the spike in cases in a statement to NBC News, but she said that "we've empowered [South Dakotans] to make the best decision for themselves, their family and their businesses, by providing them with timely and accurate health information as it becomes available," and she highlighted the vaccination rollout in the state. The North Dakota Health Department didn't respond to a request for comment.
Dr. Shankar Kurra, vice president of medical affairs at Monument Health Rapid City Hospital in South Dakota, said the personal impact of Covid-19 was the main force behind the rise in masking in the state.
"Folks started paying attention, though late, which did contribute to the decline," he said, referring to the fall in cases.
The statewide mandates, Carson said, made a noticeable difference in how North Dakota's case numbers fell compared to South Dakota's.
"Cases fell more slowly in South Dakota than in North Dakota," he said. What's more, "although recorded cases of positive Covid-19 tests were roughly the same in both states, North Dakota was issuing about four times as many tests as South Dakota at the time and had a positivity rate that was about four times lower."
Since the beginning of the pandemic, North Dakota has tested 7 percent more of its population than South Dakota. Nineteen percent of tests are still positive in South Dakota, according to Johns Hopkins University, compared to less than 4 percent in North Dakota.
Brown said that in Brookings, people did eventually start wearing masks — and they continue to in some cases — but other risky behaviors didn't stop. "The bar scene didn't seem to slow down much from what I could tell on social media," he said, adding that restaurants appeared to fill more takeout orders during the surge but that indoor dining continued.
A spike in natural immunity
Experts say another reason case numbers rose and fell sharply was that many people were infected around the same time.
Clusters of infections sprung up in groups that frequented the same places and perhaps took greater risks — for example, friends who went to bars together, Carson said. Infection rates fell as those groups recovered and were likely to have become immune and unable to spread the virus for several months.
Indeed, Carson and Kurra credit the hyperlocalized clusters of herd immunity as a key factor that helped curb the surge of cases in the Dakotas.
At least 1 in 9 South Dakotans and 1 in 7 North Dakotans have tested positive — twice as many cases per capita as in New York. Carson said the real number is likely to be double that.
The jury's still out on how long natural immunity lasts; some studies have shown that it can fade after three months.
"We're all coming to the end of that 90-day cycle now, so we are worried there will be a second spike," said Tessa Johnson, president of the North Dakota Nurses Association, who works in a long-term care facility.
Regardless of how long natural antibodies remain effective against infection, both states haven't had enough cases to reach statewide herd immunity. Johnson worried that case numbers will spike again because so many people had the virus at the same time.
If people stop taking precautions to stop the spread of the virus, risky behaviors will ultimately expose those who haven't yet contracted the virus or been vaccinated.
"It's still too soon to let go of the gas at this point. Even with the vaccine, we still need to live in the virtual world before we can safely go back to normalcy," Johnson said.
Meanwhile, in the absence of significant state government intervention, the handful of hospital systems that dominate health care in the Dakotas took charge. Their approach had certain benefits.
The three main health systems that operate in South Dakota — Monument Health, Avera Health and Sanford Health — were responsible for working with community organizations to promote prevention and address misinformation, as well as devising plans to administer tests and vaccinations.
"The state gave the awesome responsibility to Monument Health to be in charge of the western half of the state," Kurra said. "That was a huge burden, but this centralized approach has made it so we can be speedy, agile and can easily coordinate with the other health systems."
Monument Health has coordinated with local health clinics in the most rural parts of the state to get doses to them as quickly as possible.
"That kind of logistical success doesn't come easy. It takes a lot of planning, but it's easier when you have just one source," he said.
Dr. Jeremy Cauwels, chief physician for Sanford Health in Sioux Falls, South Dakota, said the hospital system — which operates in both states — recognized and addressed vaccination challenges early on. That played a crucial role in successful vaccine distribution efforts in both states.
"Any time you have a vaccine that you have to treat differently, such as the cold storage, there are going to be extra challenges," he said, referring to the Pfizer-BioNTech vaccine, which requires ultracold freezers. "But we saw those obstacles months beforehand and had nine freezers in distribution sites before the vaccinations hit."
In North Dakota, Carson credits Molly Howell, the immunization program manager at the state Health Department, who started creating a vaccination plan back in August. Both states also coordinated with pharmacies early on, delegating to them the task of administering vaccinations in long-term care facilities.
"In small, rural states, everybody knows each other, and I think having that personal connection allows for a more expedited and less bureaucratic process," said Carson, who participates in a weekly call among experts who are heavily involved in the state's response.
In addition to hospital systems, the Indian Health Service has been coordinating vaccination efforts for the states' large Native American populations, which have been hit disproportionately hard.
The agency has been careful to work closely with tribal communities to design distribution plans based on each local community, because tribal leaders and members are in the best position to understand their health care needs and priorities, an Indian Health Service representative said in a statement.
The vaccination rate on reservations in the Great Plains Area (which also includes reservations in Nebraska and Iowa) is about 14,000 doses per 100,000 people — comparable to the rates elsewhere in the Dakotas.
The misinformation threat
Despite the high vaccination rates in both states, Johnson said uptake in North Dakota was "disappointing."
Although every resident at the long-term care facility where she works has been vaccinated, she estimates that the vaccination rate among staff members is only 25 percent.
Carson worries that it is a trend across the state — one that he attributed to misinformation about the vaccines.
Kurra estimated that in South Dakota, vaccination uptake is at 60 percent; Cauwels estimated the rate to be slightly higher among health care workers. Experts don't yet know how many people will need to be vaccinated to reach herd immunity, but if enough people decline vaccinations, the virus will have an opportunity to spread and mutate, which could make vaccines less effective against new variants that emerge.
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The North Dakota Health Department has taken to social media to address specific misinformation about the vaccines. In South Dakota, the task has largely been left to doctors like Kurra. Since the start of the pandemic, Kurra has hosted weekly Facebook Live events and conference calls, and he has regularly appeared on local news stations to address people's questions about Covid-19. His focus is now on the vaccines.
"People hold on to misinformation, but health systems have the unique advantage of being a trusted source, and we have to leverage that," Kurra said.
Right now, vaccination is the best way to prevent further outbreaks.
Carson said, "We're watching the coasts contend with second spikes, and we can avoid another surge here by getting as many vaccinations out as we can."