The Medicine Wheel: informing the management of tuberculosis outbreaks in Indigenous communities.

Many Indigenous communities in Canada experience endemic tuberculosis with superimposed periodic epidemic outbreaks. Failures in outbreak management have resulted in the "seeding" of future infection and disease. In this paper we present a model that may be used in planning, implementation and review of tuberculosis outbreak management in Cree Indigenous communities in Canada, based on the Medicine Wheel, a paradigm for holistic living. In the context of tuberculosis management, the Medicine Wheel provides a path for the establishment of respectful cross-cultural relationships, the expression of values through action, true community engagement and partnership, and the establishment of culture-based processes of transparency, accountability and change.

Protective effects of prior third dose mRNA vaccination in rural nursing home residents during SARS-CoV-2 outbreaks.

BACKGROUND: In Canada, mortality due to SARS-CoV-2 disproportionately impacted residents of nursing homes (NH). In November 2021, NH residents in the Canadian province of Manitoba became eligible to receive three doses of mRNA vaccine but coverage with three doses has not been universal. The objective of this study was to compare the protection from infection conferred by one, two, and three doses of COVID-19 mRNA vaccine compared to no vaccination among residents of nursing homes experiencing SARS-CoV-2 outbreaks. METHODS: Infection Prevention and Control reports from 8 rural nursing homes experiencing outbreaks of SARS-CoV-2 between January 6, 2022, and March 5, 2022, were analyzed. Attack rates and the number needed to vaccinate (NNV) were calculated. RESULTS: SARS-CoV-2 attack rate was 65% among NH residents not vaccinated, 58% among residents who received 1-2 doses of mRNA COVID-19 vaccine, and 28% among residents who had received 3 vaccine doses. The NNV to prevent one nursing home resident from SARS-CoV-2 infection during an outbreak was 3 for a vaccination with 3 doses and 14 for 1-2 doses of COVID-19 mRNA vaccine. The superiority of receiving the third dose was statistically significant compared to 1-2 doses (Chi-Squared, p < 0.00001). CONCLUSIONS: Nursing home residents who received three doses of COVID-19 mRNA vaccine were at lower risk of SARS-CoV-2 infection compared to those who received 1-2 doses. Our analyses lend support to the protective effects of the third dose of mRNA vaccine for NH residents in the event of a SARS-CoV-2 outbreak.

HLA-A, B, DRB1, DQA1, DQB1 alleles and haplotype frequencies in Dene and Cree cohorts in Manitoba, Canada.

BACKGROUND: First Nations in the Canadian province of Manitoba have disproportionately high rates of epidemic and endemic TB. Gene polymorphisms that modulate HLA Class I and II antigens are among the risk markers for TB, along with other biologic, and social determinants of health. HLA-A, B, DRB1, DQA1, DQB1 were typed in two Manitoba First Nation indigenous groups to identify and compare the frequency of gene polymorphisms that may influence susceptibility or resistance to TB. METHODS: Participants who self-identified as either Dene or Cree enrolled into the study from two First Nation communities in Manitoba, Canada. Genomic DNA was extracted from blood samples collected with informed consent from Dene (N=63) and Cree (N=42) First Nation study participants. Participants self-reported having treated active TB, treated latent TB or no TB. HLA Class I and II molecules were typed using sequence-specific oligonucleotide (SSO) probes from commercially available kits. RESULTS: The rates of treated active and latent TB were marginally higher among the Dene than the Cree participants (p=0.112). Class I and II HLA loci were in Hardy-Weinberg equilibrium in both the Dene and Cree groups. In this exploratory analysis of TB and HLA allele frequencies in Dene and Cree cohorts HLA-A*03 and HLA-DQB1*05:03 were significantly associated with TB. CONCLUSIONS: The high incidence of TB in both Dene and Cree populations in Canada requires both biomedical and socioeconomic prevention and control measures. Among the former, an understanding of HLA diversity among First Nations groups may aid the development of new effective vaccine and therapeutic modalities that depend on the interaction between small molecules and specific HLA epitopes.

Functional gene polymorphisms in canadian aboriginal populations with high rates of tuberculosis.

The present study determined whether a pattern of functional single-nucleotide polymorphisms (SNPs) was present that could predispose a Dené cohort to a suboptimal response to Mycobacterium tuberculosis. Compared with a Caucasian cohort, the Dené and Cree were found to maintain a significantly higher frequency of SNPs associated with low expression of vitamin D receptor (VDR), interferon (IFN)-gamma (+874), and tumor necrosis factor-alpha (-308) and high production of monocyte chemoattractant protein (MCP)-1 (-2518) and interleukin (IL)-6 (-174). Given the roles played by IFN-gamma and VDR in facilitating macrophage containment of M. tuberculosis and the opposing role of MCP-1 and IL-6, the observed allelic variation by ethnicity may in part contribute to the high rates of tuberculosis among the Dené.