Individual and Geospatial Determinants of Health Associated With School-Based Human Papillomavirus Immunization in Alberta: Population-Based Cohort Study

BACKGROUND

Human papillomavirus (HPV) infection causes nearly all cervical cancer cases and is a cause of anogenital and oropharyngeal cancers. The incidence of HPV-associated cancers is inequitable, with an increased burden on marginalized groups in high-income countries. Understanding how immunization status varies by material and social deprivation, health system, and geospatial factors is valuable for prioritizing and planning HPV immunization interventions.

OBJECTIVE

The objective of this study was to describe school-based HPV immunization rates by individual and geospatial determinants of health in Alberta, Canada.

METHODS

Health administrative data for male and female individuals born in 2004 in Alberta were used to determine HPV immunization status based on age and the number of doses administered in schools during the 2014/2015-2018/2019 school years. Immunization status and its relationship with material and social deprivation and health system factors were assessed by a logistic regression model. Geospatial clustering was assessed using Getis-Ord Gi* hot spot analysis. Mean scores of material and social deprivation and health system factors were compared between hot and cold spots without full HPV immunization using independent samples t tests. A multidisciplinary team comprising researchers and knowledge users formed a co-design team to design the study protocol and review the study results.

RESULTS

The cohort consisted of 45,207 youths. In the adjusted model, the odds of those who did not see their general practitioner (GP) within 3 years before turning 10 years old and not being fully immunized were 1.965 times higher (95% CI 1.855-2.080) than those who did see their GP. The odds of health system users with health conditions and health system nonusers not being fully immunized were 1.092 (95% CI 1.006-1.185) and 1.831 (95% CI 1.678-1.998) times higher, respectively, than health system users without health conditions. The odds of those who lived in areas with the most material and social deprivation not being fully immunized were 1.287 (95% CI 1.200-1.381) and 1.099 (95% CI 1.029-1.174) times higher, respectively, than those who lived in areas with the least deprivation. The odds of those who lived in rural areas not being fully immunized were 1.428 times higher (95% CI 1.359-1.501) than those who lived in urban areas. Significant hot spot clusters of individuals without full HPV immunization exist in rural locations on the northern and eastern regions of Alberta. Hot spots had significantly worse mean material deprivation scores (P=.008) and fewer GP visits (P=.001) than cold spots.

CONCLUSIONS

Findings suggest that material and social deprivation, health system access, and rural residency impact HPV immunization. Such factors should be considered by public health professionals in other jurisdictions and will be used by the Alberta co-design team when tailoring programs to increase HPV vaccine uptake in priority populations and regions.

School-based vaccination program against HPV and Hepatitis B: A longitudinal analysis of vaccine coverage between 2015 and 2021 in Quebec

BACKGROUND

HPV vaccination prevents cancers, including 90% of cervical cancer. Since 2008, a school-based HPV vaccination program has been implemented in Quebec, but vaccine coverage is suboptimal. The COVID-19 pandemic disrupted school-based vaccination programs. This study aimed to assess variation in HPV vaccination coverage in the school-based program between 2015 and 2022 in Quebec and to identify sociodemographic characteristics associated with non-vaccination.

METHODS

HPV vaccine coverage data were extracted from the Quebec Immunization Registry for students in Grade 4 and matched to the 2016 Canadian census sociodemographic data. Descriptive analysis was conducted to explore individual-level vaccine coverage according to sociodemographic data. A Generalized Estimating Equations model assessed the independent association between non-vaccination and students' sociodemographic characteristics.

RESULTS

HPV vaccine coverage (at least one dose) was 84% in 2018-2019 and 85% in 2019-2020. A decrease was observed during the pandemic. In 2020-2021, the HPV vaccine coverage (at least one dose) was 52% (at the end of the school year) and rose to 84% with intense catch-up activities. In 2021-2022, the coverage was slightly lower than before the pandemic (81%). Factors in the dissemination area were statistically significantly associated with non-vaccination: material (p-value = 0.0001) and social deprivation index (p-value = 0.0048), the proportion of immigration (p-value < 0.0001), and the language spoken at home (English (p-value = 0.0318), other than French or English (p-value = 0.0001).

CONCLUSION

School-based vaccination programs offer equitable access to vaccination, and our analysis showed that some groups have consistently lower vaccine acceptance and uptake. Strategies to improve HPV vaccine coverage should target children living in areas with a higher proportion of immigrants, non-French speakers, and people from underprivileged backgrounds. Although it is too early to assess the full impact of COVID-19 on school-based programs in Quebec, it remains important to ensure that catch-up strategies are implemented for missed doses.

"The problem is not lack of information": A qualitative study of parents and school nurses' perceptions of barriers and potential solutions for HPV vaccination in schools

BACKGROUND

HPV vaccination has been offered in school programs for over a decade in Quebec, Canada, but the vaccine coverages are not reaching the target coverage in several regions. This qualitative study aimed to describe barriers and enabling conditions of HPV vaccination as perceived by parents and school nurses and identify potential solutions to improve HPV vaccine uptake rates and acceptance in school-based programs.

METHODS

Three focus group discussions were conducted with parents of children in Grades 2 or 3 who were unsure or unwilling to vaccinate. Individual interviews were conducted with 24 school nurses. A thematic content analysis was performed using N'Vivo.

RESULTS

The main parental questions and concerns regarding the HPV vaccination were the children's young age, the possible side effects, the rationale behind boys' vaccination and the possible interaction with COVID-19 vaccination. Except for interaction with COVID-19 vaccination, these concerns remain similar to those identified before the pandemic. Interviews highlighted that the information on HPV vaccination provided by the public was not well understood by parents. Parents suggested different tools to access information tailored to their concerns and situation. From the nurses' perspective, HPV vaccination promotion tools such as decision-aids and social media communication campaigns were needed and could reduce their work.

CONCLUSION

COVID-19 may have disrupted the acceptance of the vaccines. While strategies to catch up on missed doses and reduce access barriers to vaccines are urgently needed, our findings highlight that a shift in attitudes toward routine vaccines may pose further challenges even if HPV vaccine coverage appears to have returned to pre-pandemic levels.

Factors influencing human papillomavirus school-based immunization in Alberta: A mixed-methods study protocol

More than 1,300 Canadians are diagnosed with cervical cancer annually, which is nearly preventable through human papillomavirus (HPV) immunization. Across Canada, coverage rates remain below the 90% target set out by the Action Plan for the Elimination of Cervical Cancer in Canada (2020-2030). To support this Plan, the Canadian Partnership Against Cancer has commissioned the Urban Public Health Network (UPHN) to coordinate a quality improvement project with Canada's school-based HPV immunization programs. In Alberta, the UPHN partnered with Alberta Health Services (AHS) for this work. This study has one overarching research question: what are parent/guardian and program stakeholder perceived barriers, enablers and opportunities to immunization for youth as part of the school-based HPV immunization program in Alberta? This study uses a mixed-methods sequential explanatory design. A survey will be emailed to a sample of Albertans with children aged 11-17 years. Questions will be based on a Conceptual Framework of Access to Health Care. Subsequent qualitative work will explore the survey's findings. Parents/guardians identifying as vaccine hesitant in the survey will be invited to participate in virtual, semi-structured, in-depth interviews. Stakeholders of the school-based immunization program will be purposively sampled from AHS' five health zones for virtual focus groups. Quantitative data will be analyzed using SAS Studio 3.6 to carry out descriptive statistics and, using logistic regression, investigate if Framework constructs are associated with parents'/guardians' decision to immunize their children. Qualitative data will be analyzed using NVivo 12 to conduct template thematic analysis guided by the Framework. Study results will provide insights for Alberta's public health practitioners to make evidence-informed decisions when tailoring the school-based HPV immunization program to increase uptake in vaccine hesitant populations. Findings will contribute to the national study, which will culminate in recommendations to increase HPV immunization uptake nationally and progress towards the 90% coverage target.