During the pandemic, Native Americans have had 2.2 times greater COVID-19 case incidence and almost quadruple the death rate of White people in Montana, according to a study today in Morbidity & Mortality Weekly Report (MMWR).
A separate MMWR report looked at COVID-19 cases and response on a 10,000-member tribal reservation in Montana, while a third detailed control efforts taken on a North Dakota reservation.
All three research teams suggest that Native American populations are disproportionately vulnerable during the pandemic and benefit from COVID-19 mitigations.
Greater case, mortality, and case-fatality rates
Compared with White people in Montana, case, mortality, and case-fatality incidence was 2.2, 3.8, and 1.7 times higher for Native Americans in the state, report the authors of the first study.
In other words, out of 100,000 Native Americans, 9,064 would contract COVID-19 infections versus 4,033. And 267 of 100,000 Native Americans with COVID-19 would die, while only 71 White people would.
The Montana Department of Public Health and Human Services reported that 49,426 of 63,339 people tested for COVID-19 were positive (78.0%), which led to 903 related deaths from March 13 to Nov 30, 2020. While an estimated 90.6% of Montana's residents are White and 7.3% are Native American, 14.3% of COVID infections were in Native Americans (7,069) and 79.0% were in White people (39,040).
More than one in five COVID-related deaths involved Native Americans (23.0%), versus 73.5% involving White people.
The median age of Native American and White COVID patients was 34 and 42, respectively, and the median age of death was 68 years in Native Americans and 82 years in White people. However, infection rates were higher in Native Americans 65 years and older (10,321 vs 8,947 per 100,000 people); whereas White people displayed lower rates in the older age-group (3,632 vs 4,137 per 100,000 people).
A variety of reasons could contribute to these COVID-19 disparities, the researchers write, including more shared or intergenerational housing, difficulties accessing healthcare and transportation, lower household incomes, and a more frontline or in-person jobs. Native Americans in Montana also have a higher prevalence of COVID-19 risk factors such as heart disease, type 2 diabetes, and cigarette smoking.
"These findings reinforce importance of using state-level surveillance to develop state and tribal COVID-19 vaccine allocation strategies and to inform local implementation of culturally appropriate public health measures that might help reduce COVID-19 incidence and mortality in [Native American] communities," write the researchers.
The researchers note their results are comparable to a 23-state study looking at cumulative incidence rate ratio (3.5 times higher in Native Americans than White people) as well as a 14-state study looking at mortality ratio (1.8 times higher in Native Americans than White people).
Community mitigations considered effective
Also in Montana, a Centers for Disease Control and Prevention (CDC)-led study looked at how COVID-19 mitigations affected case rates at the Blackfeet Tribal Reservation (population 10,629) from June to December 2020. Over the study's duration, case incidence peaked at 6.40 per 100,000 per day on Oct 5 and then receded to 0.19 on Nov 7 through efforts such as enforced stay-at-home orders, mask mandates, and remote schooling.
From Jun 16 onward, 1,180 COVID-19 cases were reported on the reservation, but case rates fluctuated as mitigations did. July saw the closure of Glacier National Park's east gate, a mandatory stay-at-home order, ongoing case investigations, and contact tracing, and during this time, average daily incidence was 0.10 cases per 100,000 people.
Soon after, though, the stay-at-home order was lifted, and infections rose among those 5 to 17 and 30 to 39 years of age after campgrounds opened in August. Eventually, these age-groups became the most infected that month. COVID-19 infections also increased among those 18 to 39 and 50 to 64 years of age after the Northwest Montana Fair and Rodeo (Aug 19 to 23) and Labor Day weekend, peaking the weekend of Sep 27.
The reservation combated this influx by re-implementing a stay-at-home order (punishable with up to 3 years in jail and $5,000 in fines) on Sep 28, mandating face masks in public, providing temporary lodging as needed, and dispatching teams to deliver medicines and food. Schools switched to remote learning and, on Thanksgiving, every household was provided a holiday meal to reduce grocery trips.
By Nov 7, case incidence decreased to 0.19 per 100,000 people by Nov 7, which the researchers attribute to these mitigations. The decline was particularly in contrast to the state's rising case incidence, which peaked to 1.54 infections per 100,000 people Nov 14.
Exposure data were limited in the reservation, but among 1,180 patients, 85.2% reported at least one household contact with COVID-19. About 1 in 6 (16.5%) of 198 patients said they were exposed at work, and 39.8% of 133 people with available data said their infection came from the community.
"The strictly enforced stay-at-home order, with increased penalties, likely contributed to the more than thirtyfold decrease in incidence by November 7," the researchers write. "In communities disproportionately affected by COVID-19, these mitigation strategies are likely to help reduce some COVID-19–associated health disparities."
COVID tracking in North Dakota reservation
The last MMWR article examined a COVID-19 outbreak in North Dakota's Spirit Lake Tribe reservation from September to November 2020.
The reservation, which is home to about 7,500 residents, went from approximately 300 new COVID-19 cases per day to about 2,260 cases by Nov 13. To help control the outbreak, the CDC worked with the tribe to build a program for case investigations and contact management, which the researchers attribute to the decline in cases.
Overall, the reservation outbreak consisted of 317 confirmed COVID-19 patients and 667 close contacts. With the help of the program, 80.1% of those with COVID-19 and 78.1% of close contacts without COVID-19 diagnoses were contacted by program staff members and instructed to isolate or quarantine within 24 hours of test results or case identification from Oct 22 to Nov 30, 2020.
COVID case investigations and close contact tracing involved daily operation and continuous staffing, not to mention the additional delivery of critical supplies and health literacy information, note the researchers. However, as Spirit Lake Tribe's COVID-19 rates plateaued at 520 to 600 cases per 100,000 persons per week, the state's overall infection rates rose from 455 to 1,137 cases per 100,000 per week.
"Using Spirit Lake community members as investigators and contact tracers aided in outreach because of their knowledge of alternate methods to reach patients or contacts (in-home or family contacts) when locating information was incomplete," the researchers add.
"This tribally managed COVID-19 case investigation and contact tracing program effectively reached Spirit Lake tribal members to provide isolation, quarantine, symptom monitoring, and support services and contributed to timely case and contact management," the researchers conclude. "This program might help guide similar programs in other tribes and the public health community."