Immunization information systems in Canada: Attributes, functionality, strengths and challenges. A Canadian Immunization Research Network study

Performance evaluation on vaccination rates monitoring report system of Shenzhen, China

To evaluate the performance of "Vaccination Rates Monitoring Report System" implemented by Shenzhen CDC, we conducted an analysis of the data quality and identify key areas for system improvement. Following evaluation guidelines provided by WHO and United States CDC, we established six evaluation attributes: representativeness, simplicity, acceptability, data reliability, stability and timeliness. In eastern, central and western regions of Shenzhen, we selected one district from each region, of which the local CDC and ten CHSCs under jurisdiction were chosen for evaluation. On-site inspections, questionnaires survey and interviews were utilized for data collection, while the Likert scale method was used for attributes rating evaluation. A total of 70 participants were surveyed, consisting of 60 CHSCs and 10 CDCs staff. The gender ratio was 1:2.5 (males to females), with the majority falling within the 25-34 age range (46%). Most participants held full-time positions (80%) and had more than 5 years of work experience (62%). The system achieved 100% coverage of all CHSCs and CDCs (100%). The cumulative percentage scores for the overall favorable options of simplicity, acceptability, data reliability, stability, and timeliness were 79%, 85%, 73%, 50%, and 71% respectively. The system operates normally with strong representativeness. Acceptability was rated as "good." Simplicity, data reliability, and system timeliness were rated as "average," while system stability was rated as "poor." Based on these survey results, developers should urgently investigate reasons for poor stability, particularly addressing concerns from CHSCs users. Additionally, the issues and shortcomings identified in other attributes should also be gradually improved.

Digital Immunization Tracking in Long-Term Care and Assisted Living Facilities

A disproportionate share of the health impacts of COVID-19 has been borne by older adults, particularly those in long-term care facilities (LTCs). Vaccination has been critical to efforts to combat this issue, but as we begin to emerge from this pandemic, questions remain about how to protect the health of residents of LTC and assisted living facilities proactively in order to prevent such a disaster from occurring again. Vaccination, not just against COVID-19, but also against other vaccine-preventable illness, will be a key component of this effort. However, there are currently substantial gaps in the uptake of vaccines recommended for older adults. Technology offers an opportunity to assist in filling these vaccination gaps. Our experiences in Fredericton, New Brunswick suggest that a digital immunization solution would facilitate better uptake of adult vaccines for older adults in assisted and independent living facilities and would help policy and decision makers to identify coverage gaps and develop interventions to protect these individuals.

Understanding Diversity of Policies, Functionalities, and Operationalization of Immunization Information Systems and Their Impact: A Targeted Review of the Literature

The COVID-19 pandemic has focused attention on the use of immunization information systems (IIS) to record and consolidate immunization records from a variety of sources to generate comprehensive patient immunization histories. Operationalization of IIS in the United States is decentralized, and as such, there are over 60 different IIS with wide variations in enabling policies and functionalities. As such, the policies that inform the development and operation of those sub-national IIS exist at the state and sometimes city levels. A targeted literature review was conducted to identify IIS policies and functionalities and assess their impact. The authors identified articles published from 2012 to 2022 that discussed or evaluated IIS policies and functionalities and screened titles, abstracts, and full text for inclusion. When selected for inclusion, authors extracted IIS policy/functionality characteristics and qualitative or quantitative outcomes of their implementation, where applicable. The search terms yielded 86 articles, of which 39 were included in the analysis. The articles were heterogeneous with respect to study design, interventions, outcomes, and effect measures. Out of the 17 IIS policies and functional components identified in the targeted literature review, the most commonly evaluated were provider-based patient reminder/recall, IIS-based centralized reminder/recall, and clinical decision support. Patient reminder/recall had the most published research and was associated with increased vaccination rates and vaccine knowledge. Despite the lack of quantitative evidence, there is a consensus that immunization data interoperability is critical to supporting IIS data quality, access, and exchange. Significant evidence gaps remain about the effectiveness of IIS functionalities and policies. Future research should evaluate the impact of policies and functionalities to guide improved utilization of IIS, increase national interoperability and standardization, and ultimately improve vaccination coverage and population health.

Self-reported Human Papillomavirus Vaccination and Vaccine Effectiveness Among Men Who Have Sex with Men: A Quantitative Bias Analysis

BACKGROUND

Self-report of human papillomavirus (HPV) vaccination has ~80-90% sensitivity and ~75-85% specificity. We measured the effect of nondifferential exposure misclassification associated with self-reported vaccination on vaccine effectiveness (VE) estimates.

METHODS

Between 2017-2019, we recruited sexually active gay, bisexual, and other men who have sex with men aged 16-30 years in Canada. VE was derived as 1-prevalence ratio × 100% for prevalent anal HPV infection comparing vaccinated (≥1 dose) to unvaccinated men using a multivariable modified Poisson regression. We conducted a multidimensional and probabilistic quantitative bias analysis to correct VE estimates.

RESULTS

Bias-corrected VE estimates were relatively stable across sensitivity values but differed from the uncorrected estimate at lower values of specificity. The median adjusted VE was 27% (2.5-97.5th simulation interval = -5-49%) in the uncorrected analysis, increasing to 39% (2.5-97.5th simulation interval = 2-65%) in the bias-corrected analysis.

CONCLUSION

A large proportion of participants erroneously reporting HPV vaccination would be required to meaningfully change VE estimates.

Trends, barriers and enablers to measles immunisation coverage in Saskatchewan, Canada: A mixed methods study

Many social, cultural, and systemic challenges affect the uptake of measles immunisation services. Prior studies have looked at the caregivers' perspectives, but little is known about the perspectives of the health care providers on the barriers of measles immunisation services in Canada. This study examined measles immunisation coverage trends across the regional health authorities in Saskatchewan and explored the barriers and enablers to measles immunisation coverage from providers' perspectives. The study adopted an explanatory sequential mixed method. We utilized the entire population of 16,582 children under two years of age available in the Saskatchewan Immunisation Management System (SIMS) registry for 2002 and 2013 in aggregate format and interviewed 18 key informants in pre-determined two-stages in 2016 and 2017. The quantitative analysis was done with Joinpoint regression modelling, while the qualitative interview data was analyzed using hybrid inductive and deductive thematic approaches. There was a 16.89%-point increase in measles immunisation coverage in the province from 56.32% to 73.21% between 2002 and 2013. There was also a persistently higher coverage among the affluent (66.95% - 82.37%) than the most deprived individuals (45.79% - 62.60%) in the study period. The annual rate of coverage change was marginally higher among the most deprived (16.81%; and average annual percentage change (AAPC) 2.0, 95% CI 1.7-2.2) than among the affluent group (15.42% and AAPC 3.0; 95% CI 2.0-4.0). While access-related issues, caregivers' fears, hesitancy, anti-vaccination challenges, and resource limitations were barriers to immunisation, improving community engagement, service delivery flexibility, targeted social responses and increasing media role were found useful to address the uptake of measles and other vaccine-preventable diseases immunisation. There is low coverage and inequity in measles immunisation uptake in Saskatchewan from social and institutional barriers. Even though there is evidence of disparity reduction among the different groups, the barriers to increasing measles immunisation coverage have implications for the health of the socio-economically deprived groups, the healthcare system and other vaccination programs. There is a need to improve policy framework for community engagement, targeted programs, and public health discourse.

Impact of the COVID-19 pandemic on vaccine coverage for early childhood vaccines in Alberta, Canada: a population-based retrospective cohort study

OBJECTIVE

To assess the impact of the COVID-19 pandemic on early childhood vaccination coverage in Alberta, Canada.

SETTING

Alberta, a western Canadian province, which has a population of 4.4 million and approximately 50 000 births annually.

DESIGN

In this retrospective cohort study, population-based administrative health data were analysed to determine the vaccination coverage for measles-containing, pertussis-containing and rotavirus vaccines.

PRIMARY OUTCOME MEASURE

We measured monthly and cumulative vaccine coverage. We assessed the absolute difference in monthly and cumulative coverage for each vaccine dose by comparing children due for vaccination in each month of 2019 and 2020, with follow-up to determine if missed doses were caught up later.

PARTICIPANTS

We included 114 178 children in the 2019 analysis cohort and 106 530 children in the 2020 analysis cohort.

RESULTS

Monthly vaccination coverage in 2020 was higher than 2019 until March, when coverage significantly declined. Comparing April 2020 to 2019, coverage was 9.9% (95% CI 7.9% to 12.0%) lower for measles vaccine; 4.9% (95% CI 3.3% to 6.5%), 7.1% (95% CI 5.2% to 9.1%), 5.2% (95% CI 3.1% to 7.4%) and 8.8% (95% CI 6.6% to 10.9%) lower for first, second, third and fourth doses of pertussis-containing vaccine, respectively; and 4.0% (95% CI 2.3% to 5.7%), 7.1% (95% CI 5.1% to 9.2%) and 4.6% (95% CI 2.4% to 6.7%) lower for first, second and third doses of rotavirus vaccine, respectively. Monthly coverage improved during May to July 2020; however, some doses experienced a second decline during September to October 2020. The cumulative coverage analysis showed that the measles-containing vaccine had the largest difference in coverage at the end of follow-up.

CONCLUSIONS

Children who were due for vaccination early in the pandemic and in Fall 2020, especially those due for measles vaccination, may require additional catch-up.

The Use of Digital Technologies to Support Vaccination Programmes in Europe: State of the Art and Best Practices from Experts' Interviews

Digitalisation offers great potential to improve vaccine uptake, supporting the need for effective life-course immunisation services. We conducted semi-structured in-depth interviews with public health experts from 10 Western European countries (Germany, Greece, Italy, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, and the United Kingdom) to assess the current level of digitalisation in immunisation programmes and retrieve data on interventions and best practices. Interviews were performed using an ad hoc questionnaire, piloted on a sample of national experts. We report a mixed level of digital technologies deployment within vaccination services across Europe: Some countries are currently developing eHealth strategies, while others have already put in place robust programmes. Institutional websites, educational videos, and electronic immunisation records are the most frequently adopted digital tools. Webinars and dashboards represent valuable resources to train and support healthcare professionals in immunisation services organisation. Text messages, email-based communication, and smartphone apps use is scattered across Europe. The main reported barrier to the implementation of digital-based programmes is the lack of resources and shared standards. Our study offers a comprehensive picture of the European context and shows the need for robust collaboration between states and international institutions to share best practices and inform the planning of digital intervention models with the aim of countering vaccine hesitancy and increasing vaccine uptake.

Using observational epidemiology to evaluate COVID-19 vaccines: integrating traditional methods with new data sources and tools

Although clinical trials are necessary for vaccine approval, observational epidemiology will be required to evaluate the long-term effectiveness, safety, and population impacts of newly approved COVID-19 vaccines under real-world field conditions. In this commentary, I argue that a hybrid approach that combines new data sources and tools, including COVID-19 vaccine registries, with traditional epidemiological methods will be needed to evaluate COVID-19 vaccines using observational epidemiology. Wherever possible, primary data collection, active surveillance, and linkage with existing population-based cohorts should be leveraged to supplement secondary data sources and passive surveillance systems. Evidence-informed public health decision making around provincial COVID-19 immunization programs will need to account for potential biases, incomplete or conflicting information, and heterogeneity across subpopulations.

Impact of the COVID-19 pandemic on the provision of routine childhood immunizations in Ontario, Canada

BACKGROUND

The COVID-19 pandemic has a worldwide impact on all health services, including childhood immunizations. In Canada, there is limited data to quantify and characterize this issue.

METHODS

We conducted a descriptive, cross-sectional study by distributing online surveys to physicians across Ontario. The survey included three sections: provider characteristics, impact of COVID-19 on professional practice, and impact of COVID-19 on routine childhood immunization services. Multivariable logistic regression identified factors associated with modification of immunization services.

RESULTS

A total of 475 respondents answered the survey from May 27th to July 3rd 2020, including 189 family physicians and 286 pediatricians. The median proportion of in-person visits reported by physicians before the pandemic was 99% and dropped to 18% during the first wave of the pandemic in Ontario. In total, 175 (44.6%) of the 392 respondents who usually provide vaccination to children acknowledged a negative impact caused by the pandemic on their immunization services, ranging from temporary closure of their practice (n = 18; 4.6%) to postponement of vaccines in certain age groups (n = 103; 26.3%). Pediatricians were more likely to experience a negative impact on their immunization services compared to family physicians (adjusted odds ratio [aOR] = 2.64, 95% CI: 1.48-4.68), as well as early career physicians compared to their more senior colleagues (aOR = 2.69, 95% CI: 1.30-5.56), whereas physicians from suburban settings were less impacted than physicians from urban settings (aOR = 0.62, 95% CI: 0.39-0.99). Some of the proposed solutions to decreased immunization services included assistance in accessing personal protective equipment, dedicated centers or practices for vaccination, universal centralized electronic immunization records and education campaigns for parents.

CONCLUSIONS

COVID-19 has caused substantial modifications to pediatric immunization services across Ontario. Strategies to mitigate barriers to immunizations during the pandemic need to be implemented in order to avoid immunity gaps that could lead to an eventual increase in vaccine preventable diseases.

The digital immunization system of the future: imagining a patient-centric, interoperable immunization information system

To ensure the effectiveness of increasingly complex immunization programs in upper-middle and high-income settings, comprehensive information systems are needed to track immunization uptake at individual and population levels. The maturity of cloud systems and mobile technologies has created new possibilities for immunization information systems. In this paper, we describe a vision for the next generation of digital immunization information systems for upper-middle and high-income settings based on our experience in Canada. These systems center on the premise that the public is engaged and informed about the immunization process beyond their interaction with primary care, and that they will be a contributor and auditor of immunization data. The digital immunization system of the future will facilitate reporting of adverse events following immunization, issue digital immunization receipts, permit identification of areas of need and allow for delivery of interventions targeting these areas. Through features like immunization reminders and targeted immunization promotion campaigns, the system will reduce many of the known barriers that influence immunization rates. In light of the global COVID-19 pandemic, adaptive digital public health information systems will be required to guide the rollout and post-market surveillance of the SARS-CoV-2 vaccine.

Vaccine hesitancy among parents of preschoolers in Canada: a systematic literature review

OBJECTIVES

The purpose was to synthesize the available literature on what factors influence vaccine hesitancy of parents of preschoolers in Canada.

METHODS

Databases (e.g., CINAHL, PubMed, OVID, Proquest) were searched for relevant research articles produced between January 2009 and October 2019. Articles were required to examine vaccine uptake in children aged 0-7, in the English language, and focused within a Canadian context. Articles were excluded if they focused on uptake of the influenza vaccine and if the study population was children with chronic health conditions. A total of 367 articles were reviewed and 12 met the criteria for inclusion in this review.

SYNTHESIS

This review found that between 50% and 70% of children are completely vaccinated at 2 years old, with up to 97% having received at least one vaccine, and 2-5% receiving no vaccines. This review found that trust and access to health care providers is significantly associated with vaccine uptake, likely more important than parents' vaccine knowledge, and may compensate for challenges related to socio-economic status and family dynamics.

CONCLUSION

Vaccine programs need to be created that are accessible to all families, with an awareness of the significant impact of trust on vaccine uptake. Future research should include consistent measures of vaccine uptake, and data from First Nation communities, and should examine how increased trust between health care providers and parents of preschool children would increase vaccine uptake in Canada.

Assessment of population immunity to measles in Ontario, Canada: a Canadian Immunization Research Network (CIRN) study

Canada eliminated measles in 1998. We conducted a sero-epidemiology study to estimate population immunity to measles in the province of Ontario, Canada and to identify groups at higher risk of outbreaks. We used a previously developed modified enzyme immunoassay to test 1,199 residual sera from patients aged 1–39 years. We re-tested negative and equivocal sera using a plaque reduction neutralization assay. We interpreted our results in the context of Ontario’s immunization program and vaccine coverage data. Of 1,199 sera, 1035 (86.3%, 95% confidence interval (CI) 84.4, 88.2) were above the measles threshold for protection, 70 (5.8%, 95% CI 4.5, 7.2) were equivocal and 94 (7.8%, 95% CI 6.3, 9.4) were negative. The proportion of positive sera was highest for those 1–5 years, with 180/199 (90.5%, 95% CI 86.4, 94.5) positive sera, and lowest for those age 12–19 years, at 158/199 (79.4%, 95% CI 73.8, 85.0). Adjusted for age, females were more likely than males to have antibody titers above the threshold of protection (odds ratio = 1.60, 95% CI 1.14, 2.24). Most of the study cohort were eligible for two measles vaccine doses, and vaccine uptake in Ontario is >90% for school-aged cohorts. We observed a higher than expected proportion of sera with antibody levels below the threshold of protection, suggesting that immunity in some Ontario age-groups may be waning, despite high vaccine coverage. Alternatively, the traditional measles correlates of protection may not be an appropriate measure of population protection in measles-eliminated settings.

Parents' Experiences and Nurses' Perceptions of Decision-Making About Childhood Immunization

BACKGROUND

Immunization in Canada is recommended not mandated, granting parents discretionary decision-making power regarding their child's immunization status. Uptake of childhood immunization at present falls below national targets. Nurses who interact with parents in the clinical setting may witness parents' decision-making experiences, attitudes, and opinions inclusive of vaccine hesitancy.

PURPOSE

The aim of this study is to understand parents' and nurses' experiences of decision-making about childhood immunization, specifically measles-mumps-rubella and/or diphtheria-tetanus-acellular pertussis.

METHODS

Thorne's interpretative description approach was used to understand parents' and nurses' experiences and perspectives about immunization. The sample was 6 nurses and 16 parents residing in northeastern Ontario.

RESULTS

Common to all participants was the goal of protection. Motivated by child protection, parents carried out three broad actions, searching for information, deliberating the information and sources to determine the relative benefits and risks of immunization, and bearing responsibility for their decision to accept, delay, or decline immunization. Nurses were motivated by child protection and population health.

CONCLUSION

Implications for nursing included integration of immunization competencies in nursing curricula, ongoing professional development, validation of parental actions for child protection, nurse-led education sessions, and engaging parents through social media to support access to reputable information.

Methods used for immunization coverage assessment in Canada, a Canadian Immunization Research Network (CIRN) study

Accurate and complete immunization data are necessary to assess vaccine coverage, safety and effectiveness. Across Canada, different methods and data sources are used to assess vaccine coverage, but these have not been systematically described. Our primary objective was to examine and describe the methods used to determine immunization coverage in Canada. The secondary objective was to compare routine infant and childhood coverage estimates derived from the Canadian 2013 Childhood National Immunization Coverage Survey (cNICS) with estimates collected from provinces and territories (P/Ts). We collected information from key informants regarding their provincial, territorial or federal methods for assessing immunization coverage. We also collected P/T coverage estimates for select antigens and birth cohorts to determine absolute differences between these and estimates from cNICS. Twenty-six individuals across 16 public health organizations participated between April and August 2015. Coverage surveys are conducted regularly for toddlers in Quebec and in one health authority in British Columbia. Across P/Ts, different methodologies for measuring coverage are used (e.g., valid doses, grace periods). Most P/Ts, except Ontario, measure up-to-date (UTD) coverage and 4 P/Ts also assess on-time coverage. The degree of concordance between P/T and cNICS coverage estimates varied by jurisdiction, antigen and age group. In addition to differences in the data sources and processes used for coverage assessment, there are also differences between Canadian P/Ts in the methods used for calculating immunization coverage. Comparisons between P/T and cNICS estimates leave remaining questions about the proportion of children fully vaccinated in Canada.

Determinants of non-vaccination and incomplete vaccination in Canadian toddlers

Vaccination coverage remains suboptimal in Canada and sporadic outbreaks of vaccine-preventable diseases such as measles and pertussis continue to occur. This study was undertaken to identify sociodemographic determinants of total non-vaccination (having never received any vaccine), non-vaccination for measles (0 doses) and incomplete vaccination for pertussis (< 4 doses) among 2-year-old Canadian children. Data from the 2013 Childhood National Immunization Coverage Survey (CNICS) were used. Associations between sociodemographic factors and outcomes were measured by multiple logistic regressions and adjusted odds ratios (aOR) were calculated. A total of 5,477 children were included in the analyses of total non-vaccination, and 3,899 children were included in the analysis of non-vaccination for measles and incomplete vaccination for pertussis. Overall, 2.7% of children (95% CI 2.0–3.3) had received no vaccine at all. Lower parental education, i.e., the responding parent having a high school diploma, trade certificate or less (compared with university graduation) was associated with total non-vaccination (aOR 1.99, 95% CI 1.02–3.91). Non-vaccination for measles was more frequent among children of single parent families (aOR 1.63, 95% CI 1.01–2.61) and those of parents with lower education (aOR 1.86, 95% CI 1.26–2.76). The odds of incomplete vaccination for pertussis was greater among children born outside Canada (aOR 3.10, 95% CI 1.73–5.58), of parents with lower education (aOR 1.92, 95% CI 1.41–2.62), and those whose household income was between $40,000 and $59,999 (aOR 1.47; 95% CI 1.04–2.07) or lower than $40,000 (aOR 1.58, 95% CI 1.13–2.22). Significant regional variation was also found for all outcomes. In conclusion, despite universal access to free childhood vaccines in Canada, regional variation and socioeconomic inequalities in vaccine uptake were still observed. Further analyses are warranted to identify barriers contributing to these variations.