Type-specific prevalence of Human Papillomavirus infection among women in the Northwest Territories, Canada

Addressing the burden of cervical cancer for Indigenous women in Latin America and the Caribbean: a call for action

Cervical cancer, primarily caused by human papillomavirus (HPV) infection, poses a significant global health challenge. Due to higher levels of poverty and health inequities, Indigenous women worldwide are more vulnerable to cervical cancer than their non-Indigenous counterparts. However, despite constituting nearly 10% of the population in Latin America and the Caribbean (LAC), the true extent of the burden of cervical cancer among Indigenous people in this region remains largely unknown. This article reviews the available information on cervical cancer incidence and mortality, as well as HPV infection prevalence, among Indigenous women in LAC. The limited existing data suggest that Indigenous women in this region face a heightened risk of cervical cancer incidence and mortality compared to non-Indigenous women. Nevertheless, a substantial knowledge gap persists that must be addressed to comprehensively assess the burden of cervical cancer among Indigenous populations, especially through enhancing cancer surveillance across LAC countries. Numerous structural, social and cultural barriers hindering Indigenous women's access to HPV vaccination and cervical cancer screening worldwide have been identified and are reviewed in this article. The discussion highlights the critical role of culturally sensitive education, community engagement, and empowerment strategies in overcoming those barriers. Drawing insights from the success of targeted strategies in certain high-income countries, the present article advocates for research, policies and healthcare interventions tailored to the unique context of LAC countries.

Infectious diseases in Indigenous populations in North America: learning from the past to create a more equitable future

The COVID-19 pandemic, although a profound reminder of endured injustices by and the disparate impact of infectious diseases on Indigenous populations, has also served as an example of Indigenous strength and the ability to thrive anew. Many infectious diseases share common risk factors that are directly tied to the ongoing effects of colonisation. We provide historical context and case studies that illustrate both challenges and successes related to infectious disease mitigation in Indigenous populations in the USA and Canada. Infectious disease disparities, driven by persistent inequities in socioeconomic determinants of health, underscore the urgent need for action. We call on governments, public health leaders, industry representatives, and researchers to reject harmful research practices and to adopt a framework for achieving sustainable improvements in the health of Indigenous people that is both adequately resourced and grounded in respect for tribal sovereignty and Indigenous knowledge.

First nations people's perspectives on barriers and supports for enhancing HPV vaccination: Foundations for sustainable, community-driven strategies

OBJECTIVE

In Canada, Indigenous people have higher human papillomavirus (HPV) infection rates, lower screening rates for cervical cancer, and higher rates of invasive cancer, leading to worse cervical cancer-related outcomes than observed in non-Indigenous Canadian women. Lingering harms from European colonization drive these health inequities and create public health challenges. Policy guidance is needed to optimize HPV vaccination rates and, thereby, decrease the burden of HPV-related illness, including high-morbidity surgical procedures and chemo-radiotherapy. The Enhancing HPV Vaccination In First Nations Populations in Alberta (EHVINA) project focuses on First Nations, a diverse subset of recognized Indigenous people in Canada, and seeks to increase HPV vaccination among girls and boys living in First Nation communities.

METHODS

Developing an effective strategy requires partnership with affected communities to better understand knowledge and perceptions about cancer, healthcare, and the HPV vaccine. A 2017 community gathering was convened to engage First Nations community members, health directors, and health services researchers in dialogue around unique barriers and supports to HPV vaccination in Alberta. Voices of community Elders, parents, health directors, and cancer survivors (n=24) are presented as qualitative evidence to help inform intervention design.

RESULTS

Key findings from discussions indicate barriers to HPV vaccination include resource constraints and service infrastructure gaps, historical mistrust in healthcare systems, impacts of changing modes of communication, and community sensitivities regarding sexual health promotion. Supports were identified as strengthened inter-generational relationships in communities.

CONCLUSIONS AND FUTURE DIRECTION

Ongoing dialogue and co-development of community-based strategies to increase HPV vaccine uptake are required. The identification of possible barriers to HPV vaccination in a Canadian Indigenous population contributes to limited global literature on this subject and may inform researchers and policy makers who work with Indigenous populations in other regions.

Barriers, supports, and effective interventions for uptake of human papillomavirus- and other vaccines within global and Canadian Indigenous peoples: a systematic review protocol

BACKGROUND

Despite the existence of human papilloma virus (HPV) vaccines with demonstrated safety and effectiveness and funded HPV vaccination programs, coverage rates are persistently lower and cervical cancer burden higher among Canadian Indigenous peoples. Barriers and supports to HPV vaccination in Indigenous peoples have not been systematically documented, nor have interventions to increase uptake in this population. This protocol aims to appraise the literature in Canadian and global Indigenous peoples, relating to documented barriers and supports to vaccination and interventions to increase acceptability/uptake or reduce hesitancy of vaccination. Although HPV vaccination is the primary focus, we anticipate only a small number of relevant studies to emerge from the search and will, therefore, employ a broad search strategy to capture literature related to both HPV vaccination and vaccination in general in global Indigenous peoples.

METHODS

Eligible studies will include global Indigenous peoples and discuss barriers or supports and/or interventions to improve uptake or to reduce hesitancy, for the HPV vaccine and/or other vaccines. Primary outcomes are documented barriers or supports or interventions. All study designs meeting inclusion criteria will be considered, without restricting by language, location, or data type. We will use an a priori search strategy, comprised of key words and controlled vocabulary terms, developed in consultation with an academic librarian, and reviewed by a second academic librarian using the PRESS checklist. We will search several electronic databases from date of inception, without restrictions. A pre-defined group of global Indigenous websites will be reviewed for relevant gray literature. Bibliographic searches will be conducted for all included studies to identify relevant reviews. Data analysis will include an inductive, qualitative, thematic synthesis and a quantitative analysis of measured barriers and supports, as well as a descriptive synthesis and quantitative summary of measures for interventions.

DISCUSSION

To our knowledge, this study will contribute the first systematic review of documented barriers, supports, and interventions for vaccination in general and for HPV vaccination. The results of this study are expected to inform future research, policies, programs, and community-driven initiatives to enhance acceptability and uptake of HPV vaccination among Indigenous peoples.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO Registration Number: CRD42017048844.

Evaluation of using composite HPV genotyping assay results to monitor human papillomavirus infection burden through simulation

Background

Researchers often group various HPV types into composite measures based on vaccine subtypes, oncogenic potential, or phylogenetic position. Composite prevalence estimates based on PCR genotyping assay results have been calculated to assess HPV infection burden and to monitor HPV vaccine effectiveness. While prevention and intervention strategies can be made based on these prevalence estimates, the discussion on how well these prevalence estimates measure the true underlying infection burdens is limited.

Methods

A simulation study was conducted to evaluate accuracy of using composite genotyping assay results to monitor HPV infection burden. Data were generated based on mathematical algorithms with prespecified type-specific infection burdens, assay sensitivity, specificity, and correlations between various HPV types. Estimated-to-true prevalence rate ratios and percent reduction of vaccine types were calculated.

Results

When “true” underlying type-specific infection burdens were prespecified as the reported prevalence in U.S. and genotyping assay with sensitivity and specificity (0.95, 0.95) was used, estimated-to-true infection prevalence ratios were 2.35, 2.29, 2.18, and 1.46, for the composite measures with 2 high-risk vaccine, 4 vaccine, 14 high-risk and 37 HPV types, respectively. Estimated-to-true prevalence ratios increased when prespecified “true” underlying infection burdens or assay specificity declined. When prespecified “true” type-specific infections of HPV 6, 11, 16 and 18 were reduced by 50%, the composite prevalence estimate of 4 vaccine types only decreased by 17% which is much lower than 48% reduction in the prespecified “true” composite prevalence.

Conclusions

Composite prevalence estimates calculated based on panels of genotyping assay results generally over-estimate the “true” underlying infection burdens and could under-estimate vaccine effectiveness. Analytical specificity of genotyping assay is as or more important than analytical sensitivity and should be considered in selecting assay to monitor HPV.

Type-specific human papillomavirus infections and Pap test findings in Inuit and non-Inuit women in Nunavut, Canada

Objective

To determine the prevalence and distribution of type-specific human papillomavirus (HPV) infections and their association with cytological outcomes in women living in the Canadian territory of Nunavut.

Methods

Surveillance of type-specific HPV infection was conducted. Cervical specimens of all Inuit, First Nations and non-Aboriginal women in Nunavut who presented for a Pap test in any clinical setting between January 2008 and March 2009 were tested for HPV infection. The association between high-grade cervical lesions and HPV type was also examined.

Results

HPV results were available for 4,043 individual women (13 to 77 years). Of those with known ethnicity (N=4,033), 89.2% were Inuit, 0.4% were First Nations and 10.4% were non-Aboriginal. First Nations women were included in all analyses except those making comparisons by ethnicity, due to the small number of individuals in this group. Overall, 29.9% of women were found to be infected with HPV (any type) and 19.9% with any high-risk HPV (type 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58 or 59). Most often, women were infected with HPV 16 (6.4%) followed by HPV 31 (3.1%). There were no statistically significant differences between Inuit and non-Aboriginal (reference group) women 20 years of age and older regarding the prevalence of any HPV (odds ratios (OR): 1.19, 95% confidence intervals (CI): 0.92-1.54), high-risk HPV (OR: 1.06, 95% CI: 0.78-1.44) or HPV 16 and 18 (OR: 0.81, 95% CI: 0.51-1.27). HPV 31 was the only type that was significantly more frequent among Inuit than non-Aboriginal women (OR: 3.95, 95% CI: 1.24-12.54). There was no difference in the overall occurrence of cervical abnormalities between non-Aboriginal and Inuit women (p-value = 0.17). HPV 16 was strongly associated with cervical dysplasia, being present in 50.9% of specimens with a high-grade lesion.

Conclusion

HPV is a significant public health issue in the territory of Nunavut. The findings presented in this article are similar to those in other studies among Inuit women, with prevalence of HPV being higher than in studies conducted among non-Inuit women in other regions of Canada. These results provide a baseline of HPV prevalence that precedes the introduction of the Nunavut HPV Immunization Program in 2010 and will allow for future evaluation. The high prevalence of HPV infection among women living in Nunavut can be reduced through immunization and associated high-grade cervical abnormalities mitigated by regular cervical screening.

Prevalência de atipias citológicas e infecção pelo papilomavírus humano de alto risco em mulheres indígenas Panará, povo indígena do Brasil Central

O objetivo do estudo foi analisar a prevalência das atipias citológicas e infecção pelo papilomavírus humano em mulheres indígenas Panará no período de 2006 a 2007. Trata-se de estudo observacional transversal, com dados obtidos por coleta de amostras cérvico-vaginais para colpocitologia oncótica e captura híbrida, exame de colposcopia e biópsia. O trabalho incluiu 86 mulheres com idades de 12 anos ou mais, com história de vida sexual ativa ou pregressa. Os resultados mostraram que 10,7% das mulheres tinham atipias citológicas e que 28,6% estavam infectadas pelo HPV de alto risco oncogênico, principalmente entre as mais jovens (média = 25,6 anos). Dessas, 41,7% foram positivas para um ou mais dos tipos de HPV de alto risco dos genótipos 16, 18 ou 45, e a maioria, 58,3%, para outros tipos de HPV de alto risco. Conclui-se que é uma população especial, susceptível ao desenvolvimento das lesões precursoras do câncer do colo do útero e vulnerável às DST. Medidas preventivas como o rastreamento populacional sistemático para o câncer cervical e imunização contra o HPV são necessárias.

The Arctic Human Health Initiative: a legacy of the International Polar Year 2007-2009

BACKGROUND

The International Polar Year (IPY) 2007-2008 represented a unique opportunity to further stimulate cooperation and coordination on Arctic health research and increase the awareness and visibility of Arctic regions. The Arctic Human Health Initiative (AHHI) was a US-led Arctic Council IPY coordinating project that aimed to build and expand on existing International Union for Circumpolar Health (IUCH) and Arctic Council human health interests. The project aimed to link researchers with potential international collaborators and to serve as a focal point for human health research, education, outreach and communication activities during the IPY. The progress of projects conducted as part of this initiative up until the end of the Arctic Council Swedish chairmanship in May 2013 is summarized in this report.

DESIGN

The overall goals of the AHHI was to increase awareness and visibility of human health concerns of Arctic peoples, foster human health research, and promote health strategies that will improve health and well-being of all Arctic residents. Proposed activities to be recognized through the initiative included: expanding research networks that will enhance surveillance and monitoring of health issues of concern to Arctic peoples, and increase collaboration and coordination of human health research; fostering research that will examine the health impact of anthropogenic pollution, rapid modernization and economic development, climate variability, infectious and chronic diseases, intentional and unintentional injuries, promoting education, outreach and communication that will focus public and political attention on Arctic health issues, using a variety of publications, printed and electronic reports from scientific conferences, symposia and workshops targeting researchers, students, communities and policy makers; promoting the translation of research into health policy and community action including implementation of prevention strategies and health promotion; and promoting synergy and strategic direction of Arctic human health research and health promotion.

RESULTS

As of 31 March, 2009, the official end of the IPY, AHHI represented a total of 38 proposals, including 21 individual Expressions of Intent (EoI), and 9 full proposals (FP), submitted to the IPY Joint Committee for review and approval from lead investigators from the US, Canada, Greenland, Norway, Finland, Sweden and the Russian Federation. In addition, there were 10 National Initiatives (NI-projects undertaken during IPY beyond the IPY Joint Committee review process). Individual project details can be viewed at www.arctichealth.org. The AHHI currently monitors the progress of 28 individual active human health projects in the following thematic areas: health network expansion (5 projects), infectious disease research (7 projects), environmental health research (7 projects), behavioral and mental health research (4 projects), and outreach education and communication (5 projects).

CONCLUSIONS

While some projects have been completed, others will continue well beyond the IPY. The IPY 2007-2008 represented a unique opportunity to further stimulate cooperation and coordination on Arctic health research and increase the awareness and visibility of Arctic regions.

The prevalence of human papillomavirus and its impact on cervical dysplasia in Northern Canada

Introduction

Certain types of the Human Papillomavirus (HPV) are sexually transmitted and highly associated with development of cervical dysplasia and cervical cancer but the distribution of HPV infection in the North, particularly amongst First Nations, Metis, and Inuit peoples, is little known. The purposes of the study are to identify the prevalence of type-specific HPV infections and the association of different HPV types with cervical dysplasia among women in Northern Canada.

Methods

This was a cross-sectional study with attendants of the routine or scheduled Pap testing program in the Northwest Territories (NWT), Nunavut, Labrador and Yukon, Canada. Approximately half of each sample was used for Pap test and the remaining was used for HPV genotyping using a Luminex-based method. Pap test results, HPV types, and demographic information were linked for analyses.

Results

Results from 14,598 specimens showed that HPV infection was approximately 50% higher among the Aboriginal than the non-Aboriginal population (27.6% vs. 18.5%). Although the most common HPV type detected was HPV 16 across region, the prevalence of other high risk HPV types was different. The age-specific HPV prevalence among Aboriginal showed a ‘U’ shape which contrasted to non-Aboriginal. The association of HPV infection with cervical dysplasia was similar in both Aboriginal and non-Aboriginal populations.

Conclusions

The HPV prevalence was higher in Northern Canada than in other Areas in Canada. The prevalence showed a higher rate of other high risk HPV infections but no difference of HPV 16/18 infections among Aboriginal in comparison with non-Aboriginal women. This study provides baseline information on HPV prevalence that may assist in surveillance and evaluation systems to track and assess HPV vaccine programs.

Type-specific prevalence of human papillomavirus in women screened for cervical cancer in Labrador, Canada

Background

A higher incidence of cervical cancer and human papillomavirus (HPV) infection has been reported in northern Canada and in First Nation, Métis and Inuit women, with some evidence to suggest that the HPV type distribution in these populations may be different from the rest of Canada.

Objective

The objective of this study was to measure the HPV type prevalence in Labrador women to determine if significant differences in HPV types could reduce the effectiveness of HPV vaccination.

Design

The prevalence of HPV types was determined in 1,370 women presenting for routine pap screening in Labrador between February and November 2010. Cervical cytology and HPV genotyping were performed on the same liquid-based cytology specimens.

Results

The overall prevalence of HPV was 21.4%; cytological abnormalities were found in 8.8% of the participants. HPV 16 and 18 were the most common high-risk HPV types. These two types were found in 52.4% of high-grade lesions. The prevalence in HPV infections was comparable across the Labrador regions.

Conclusions

The present results support the potential effectiveness of the HPV immunization program in Labrador.

Factors associated with human papillomavirus infection among women in the Northwest Territories

BACKGROUND

In some regions, Aboriginal women have higher rates of cervical cancer compared to other Canadian women. However, little data are available regarding the co-factors of HPV infection in the Aboriginal population of Canada. We examined factors associated with high-risk human papillomavirus (HR-HPV) infection in a population of women (both Aboriginal and non-Aboriginal) in the Northwest Territories (NWT).

METHODS

We used a cross-sectional design using a convenience sample of all women aged 14 years or older presenting for Papanicolaou (Pap) testing across all regions of the NWT from March 2009 to March 2010. Women answered a questionnaire on demographic characteristics, sexual behaviour, and gynaecological and obstetrical events. We used multiple regression analysis to explore factors associated with HR-HPV infection according to age and cultural background. HPV typing was done using the Luminex assay.

RESULTS

Of the total 1,279 participants, 178 had missing HPV results. We obtained data on 1,101 women and overall HR-HPV prevalence was 14.2%. Younger age, single marital status, Aboriginal background, current smoking, lifetime deliveries, use of hormonal contraceptives, and the numbers of sexual partners in the last year were associated with prevalent HR-HPV.

DISCUSSION

Our findings tend to indicate that Aboriginal women have different predictors of HR-HPV than non-Aboriginal women that may affect HPV progression to cervical cancer. These findings can help to better target public health practices for the women at higher risk of HPV infection and cervical cancer.