Sexual behaviour among Kenyan adolescents enrolled in an efficacy trial of a smartphone game to prevent HIV: a cross-sectional analysis of baseline data

Sexual behaviour of adolescents is contextual, with various determinants affecting sexual activity and age of sexual debut. Insight into sexual activity among young adolescents has the potential to influence appropriate sexual and reproductive health interventions. For this analysis, adolescents were recruited as part of the Tumaini smartphone game efficacy trial. Data collection included a self-administered behavioural survey and blood test for HIV and HSV-2. Descriptive statistics were calculated for demographics and measures of sexual behaviour and behavioural intent based on gender and sexual experience, with associations assessed using chi-square tests, t-tests and Wilcoxon rank sum tests as appropriate. We enrolled 996 adolescents, mean age 14 years and 2.2% HSV-2 positivity. Overall, 15% of the adolescents were sexually experienced, this being associated with lower socio-economic status (p = 0.01), household food insecurity (p = 0.008), a living situation without both parents (p < 0.01), substance use (p = 0.02), no adult conversation about future goals (p = 0.003), conversations about condoms (p = 0.01), with some gender disparity within these factors. Among those sexually experienced, 21.7% reported unwilling sex; 17.5% had engaged in transactional sex; 57.8% had willing first sex, of whom 60.9% reported no condom use. Among those abstaining, female adolescents were less likely to contemplate condom use at first sex (p = 0.006). Our findings determine that young sexually active adolescents are likely engaging in unprotected sex and having unwilling sexual experiences. Socio-economic status, living situation and parental monitoring remain significant factors associated with sexual experience among young adolescents. In this context, early adolescence is an opportunity to provide age- and developmentally appropriate education about safer sex practices.Trial registration: ClinicalTrials.gov identifier: NCT04437667.

COVID-19 Diagnosis, Severity, and Long COVID Among U.S. Adolescents, National Health Interview Survey, 2022

PURPOSE

Understanding disparities in COVID-19 outcomes, overall and stratified by vaccination status, is important for developing targeted strategies to increase vaccination coverage and protect adolescents from COVID-19.

DESIGN

The 2022 National Health Interview Survey (NHIS) is a cross-sectional nationally representative household survey of U.S. adults.

SETTING

A probability sample of households in the U.S.

SAMPLE

One child aged 12-17 years is randomly selected from each family in the household. A knowledgeable adult (eg, parent or guardian), responds on behalf of the child through an in-person interview (response rate = 49.9%).

MEASURES

Input measures-sociodemographic characteristics and COVID-19 vaccination status; output measures-ever had COVID-19, moderate/severe COVID-19, long COVID.

ANALYSIS

Prevalence of COVID-19 outcomes was assessed for adolescents aged 12-17 years. Factors associated with each COVID-19 outcome were assessed with multivariable logistic regression analyses.

RESULTS

Among 2758 adolescents aged 12-17 years in 2022, 60.5% had received ≥1 dose of COVID-19 vaccine, 30.2% had ever been diagnosed by a doctor that they had COVID-19, 29.5% had moderate/severe COVID-19, and 6.2% had long COVID. Adolescents who were vaccinated with ≥1 dose were less likely to be diagnosed with COVID-19 (aOR = .79) and less likely to have long COVID (aOR = .30).

CONCLUSION

Targeted messaging to highlight the importance of early treatment, the harms of long COVID-19, and the benefits of vaccination in protecting against long-term effects may be necessary to ensure that all adolescents and their families are adequately protected.

Development and validation of VaxConcerns: A taxonomy of vaccine concerns and misinformation with Crowdsource-Viability

We present VaxConcerns, a taxonomy for vaccine concerns and misinformation. VaxConcerns is an easy-to-teach taxonomy of concerns and misinformation commonly found among online anti-vaccination media and is evaluated to produce high-quality data annotations among crowdsource workers, opening the potential adoption of the framework far beyond just academic or medical communities. The taxonomy shows high agreement among experts and outperforms existing taxonomies for vaccine concerns and misinformation when presented to non-expert users. Our proof-of-concept study on the changes in anti-vaccination content during the COVID-19 pandemic indicate impactful future use cases, such as longitudinal studies of the shift in vaccine concerns over time.

Child and adolescent COVID-19 vaccination coverage by educational setting, United States

OBJECTIVES

The COVID-19 pandemic changed the setting of education for many children in the U.S. Understanding COVID-19 vaccination coverage by educational setting is important for developing targeted messages, increasing parents' confidence in COVID-19 vaccines, and protecting all children from severe effects of COVID-19 infection.

STUDY DESIGN/METHODS

Using data from the Household Pulse Survey (n = 25,173) collected from December 9-19, 2022, January 4-16, 2023, and February 1-13, 2023, this study assessed factors associated with COVID-19 vaccination and reasons for non-vaccination among school-aged children 5-11 and adolescents 12-17 by educational setting.

RESULTS

Among children 5-11 years, COVID-19 vaccination coverage was higher among those who received in-person instruction (53.7%) compared to those who were homeschooled (32.5%). Furthermore, among adolescents 12-17 years, COVID-19 vaccination coverage was higher among those who received in-person instruction (73.5%) or virtual/online instruction (70.1%) compared to those who were homeschooled (51.0%). Children and adolescents were more likely to be vaccinated if the parental respondent had been vaccinated compared to those who had not. Among children and adolescents who were homeschooled, main reasons for non-vaccination were concern about side effects (45.4-51.6%), lack of trust in COVID-19 vaccines (45.0-50.9%), and lack of trust in the government (32.7-39.2%).

CONCLUSIONS

Children and adolescents who were home-schooled during the pandemic had lower vaccination coverage than those who attended school in person, and adolescents who were home-schooled had lower vaccination coverage than those who received virtual instruction. Based on the reasons for non-vaccination identified in this study, increasing parental confidence in vaccines, and reducing barriers to access are important for supporting COVID-19 vaccination for school-age children.

Facilitators and barriers of HPV vaccination: a qualitative study in rural Georgia

Introduction

Human papillomavirus (HPV) vaccination protects against HPV-associated cancers and genital warts. Healthy People 2030 goal for HPV vaccine uptake is 80%, but as of 2021, only 58.5% of adolescents are up to date in Georgia. The purpose of the study is to assess the attitudes, vaccine practices, facilitators, and barriers to receiving the HPV vaccine in southwest Georgia.

Methods

We conducted 40 semi-structured interviews with three different audiences (young adults, parents, and providers and public health professionals) guided by the P3 (patient-, provider-, practice-levels) model and used deductive coding approach. Young adults and parents were interviewed to assess their perceived benefits, barriers, and susceptibility of the HPV vaccine. Providers and public health professionals were interviewed about facilitators and barriers of patients receiving the HPV vaccine in their communities.

Results

Out of the 40 interviews: 10 young adults, 20 parents, and 10 providers and public health professionals were interviewed. Emerging facilitator themes to increase the uptake of the HPV vaccine included existing knowledge (patient level), providers' approach to the HPV vaccine recommendations (provider level) and immunization reminders (practice level). Barrier themes were lack of knowledge around HPV and the HPV vaccine (patient level), need for strong provider recommendation and discussing the vaccine with patients (provider level), and limited patient reminders and information (practice level).

Conclusions

These interviews revealed key themes around education, knowledge, importance of immunization reminders, and approaches to increasing the HPV vaccination in rural Georgia. This data can inform future interventions across all levels (patient, provider, practice, policy, etc.) to increase HPV vaccination rates in rural communities.

Vaccination patterns and up-to-date status of children 19-35 months, 2011-2021

INTRODUCTION

Being up-to-date with all recommended vaccines is needed to protect children from vaccine preventable diseases. Understanding vaccination patterns is needed to develop messaging and strategies to increase vaccination uptake and confidence.

METHODS

Data from the 2011 to 2021 National Immunization Surveys was used to assess trends and disparities in vaccination patterns, zero vaccination status, and up-to-date status of U.S. children by 19-35 months.

RESULTS

From 2011 to 2021, adherence to the recommended schedule using the stringent definition increased from 35.7 % to 52.2 % (p < 0.01), adherence to the alternate schedule decreased from 28.2 % to 15.1 % (p < 0.01), and proportion of children who were not up-to-date decreased from 49.0 % to 33.3 % (p < 0.01). However, the proportion of children who had zero vaccinations did not change from 2011 (0.9 %) to 2021 (0.9 %; p = 0.08). In 2021, children 19-23 months were less likely to follow the recommended schedule than children 24-29 months (49.2 % compared to 56.4 %, p < 0.01). Adherence to the recommended schedule among children 19-23 months decreased in 2021 compared to 2020 overall and for some subpopulations (e.g. those with non-Hispanic (NH) Black parents (33.2 % compared to 44.9 %, p < 0.01). Furthermore, it was lowest among children of NH Black parents living at or below the federal poverty level (31.2 %) compared to their respective NH White counterparts (43.6 %, p < 0.01).

CONCLUSIONS

While there were overall increases in adherence to the recommended schedule from 2011 to 2021, a sustained catch-up program is needed to prevent missed vaccinations and achieve equitable vaccination coverage for all children.

Interactive Narrative-Based Digital Health Interventions for Vaccine Communication: Protocol for a Scoping Review

BACKGROUND

Interactive narrative-based digital health interventions hold promise for effectively addressing the complex determinants of vaccine hesitancy and promoting effective communication across a wide range of settings and vaccine types. Synthesizing evidence related to the implementation and evaluation of these interventions could offer valuable perspectives for shaping future strategies in vaccine communication. Prior systematic and scoping reviews have examined narrative-based vaccine communication interventions but not the inclusion of interactivity in such interventions.

OBJECTIVE

The overall objective of the scoping review is to summarize the evidence on the use of interactive narrative-based digital health interventions for vaccine communication. Specific research questions focus on describing the use of interactive narrative-based digital health interventions (RQ1), describing evaluations of the impact of interactive narrative-based digital health interventions on promoting vaccine uptake (RQ2), and factors associated with their implementation (RQ3).

METHODS

A detailed search string will be used to search the following databases for records that are relevant to the review questions: PubMed, Embase, Scopus, Web of Science, CINAHL, and PsycINFO. Two reviewers will independently screen the titles and abstracts of identified records against the predefined eligibility criteria. Subsequently, eligible records will undergo comprehensive full-text screening by 2 independent reviewers to assess their relevance to review questions. A data charting tool will be developed and used to extract relevant information from the included articles. The extracted information will be analyzed following the review questions and presented as a narrative summary. Tabular or graphical representations will be used to display review findings, as relevant.

RESULTS

Public health informationists were consulted to develop the detailed search strategy. The final search string comprised terms related to narrative communication, digital health, and vaccines. The search string was customized to each proposed publication database and implemented on April 18, 2023. A total of 4474 unique records were identified using the search strategy and imported into the Covidence (Veritas Health Innovation Ltd) review management software for title and abstract screening. Title and abstract screening of identified records are ongoing as of December 29, 2023.

CONCLUSIONS

To our knowledge, this will be the first scoping review to investigate the features of interactive narrative-based digital health interventions and their role in vaccine communication. The goal of this study is to provide a comprehensive overview of the current research landscape and identify prevailing gaps in knowledge. The findings will provide insights for future research and development of novel applications of interactive narrative-based digital health vaccine communication interventions.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/51137.

Population Attributable Fraction of Nonvaccination of COVID-19 Due to Vaccine Hesitancy, United States, 2021

Understanding the extent of coronavirus disease 2019 (COVID-19) nonvaccination attributable to vaccine hesitancy versus other barriers can help prioritize approaches for increasing vaccination uptake. Using data from the Centers for Disease Control and Prevention's Research and Development Survey, a nationally representative survey fielded from May 1 to June 30, 2021 (n = 5,458), we examined the adjusted population attribution fraction (PAF) of COVID-19 vaccine hesitancy attributed to nonvaccination according to sociodemographic characteristics and health-related variables. Overall, the adjusted PAF of nonvaccination attributed to vaccine hesitancy was 76.1%. The PAF was highest among adults who were ≥50 years of age (87.9%), were non-Hispanic White (83.7%), had a bachelor's degree or higher (82.7%), had an annual household income of at least $75,000 (85.5%), were insured (82.4%), and had a usual place for health care (80.7%). The PAF was lower for those who were current smokers (65.3%) compared with never smokers (77.9%), those who had anxiety or depression (65.2%) compared with those who did not (80.1%), and those who had a disability (64.5%) compared with those who did not (79.2%). Disparities in PAF suggest areas for prioritization of efforts for intervention and development of messaging campaigns that address all barriers to uptake, including hesitancy and access, to advance health equity and protect individuals from COVID-19.

Descriptive epidemiology of age at HPV vaccination: Analysis using the 2020 NIS-Teen

Human papillomavirus (HPV) vaccination uptake in the United States remains suboptimal, and continues to trail that of tetanus, diphtheria, and acellular pertussis (Tdap) vaccination and quadrivalent meningococcal conjugate vaccination (MCV4). This is despite these three vaccines all being recommended for routine adolescent use within the 2005-2006 time period. One strategy to improve HPV vaccination is starting the vaccine series at the first opportunity - currently as young as 9 years of age. Little is known about the epidemiology of age at HPV vaccination, and the frequency of vaccination occurring at 9-10 years of age. Using 2020 National Immunization Survey-Teen (NIS-Teen) data, we analyzed age at HPV vaccine initiation and proportion of initiators completing the HPV vaccine series relative to age at initiation. Overall, 4.0% of US adolescents initiated HPV vaccination at 9-10 years of age, with higher initiation among younger birth cohorts (4.8% for 13-year-olds and 5.1% for 14-year-olds) than older cohorts (3.1% for both 16 and 17 year-olds). Age cohorts maximized HPV vaccine completion after 3-4 years. Among those initiating at ages 9-10, 93% of 13-year-olds completed the series. Among those initiating at 11-12, completion rates rose from 66% among 13-year-olds to 90.2% among 16-year-olds. Among those initiating at age 13-14, completion rose from 61% among 15-year-olds to 84.9% among 17-year-olds. This manuscript serves as a starting point of comparison for future epidemiologic evaluations of HPV vaccination at the first opportunity.

U.S. Vietnamese parents' trusted sources of information and preferences for intervention messaging about HPV vaccination: A mixed methods study

Objective

Assess trusted sources of information, perceived message effectiveness, and preferred dissemination strategies regarding adolescent HPV vaccination among U.S. Vietnamese parents.

Methods

Data came from an observational, explanatory sequential mixed-methods study with U.S. Vietnamese parents of adolescents (408 survey participants; 32 interview participants). Surveys and interviews were conducted in both Vietnamese and English. Mixed-methods data were integrated and analyzed for confirmation, expansion, or discordance.

Results

Both quantitative and qualitative findings confirm high trust in HPV vaccination information from providers, government agencies, and cancer organizations. Messages perceived as effective emphasize vaccine safety, experts' endorsement, importance of vaccination prior to HPV exposure, and preventable cancers. Qualitative findings expanded quantitative results, demonstrating a desire for evidence-based information in the Vietnamese language and addressing cultural concerns (e.g., effectiveness or potential side effects specific to Vietnamese adolescents, whether parents should delay HPV vaccination for Vietnamese adolescents). Quantitative and qualitative findings were incongruent about whether parents would trust information about HPV vaccination that is disseminated via social media.

Conclusion

We identified credible messengers, feasible strategies, and elements of impactful messages for interventions to increase adolescent HPV vaccination for U.S. Vietnamese.

Innovation

We focus on a high-risk, underserved population and integrate mixed-methods design and analysis.

Disparities in child and adolescent COVID-19 vaccination coverage and parental intent toward vaccinations for their children and adolescents

INTRODUCTION

Despite recommendations for COVID-19 primary series completion and booster doses for children and adolescents, coverage has been less than optimal, particularly in some subpopulations. This study explored disparities in childhood/adolescent COVID-19 vaccination, parental intent to vaccinate their children and adolescents, and reasons for non-vaccination in the US.

METHODS

Using the U.S. Census Bureau's Household Pulse Survey (HPS), we analyzed households with children aged <18 years using data collected from September 14 to November 14, 2022 (n = 44,929). Child and adolescent COVID-19 vaccination coverage (≥1 dose, completed primary series, and booster vaccination) and parental intentions toward vaccination were assessed by sociodemographic characteristics. Factors associated with child and adolescent vaccination coverage were examined using multivariable regression models. Reasons for non-vaccination were assessed overall, by the child's age group and respondent's age group.

RESULTS

Overall, approximately half (50.1%) of children aged < 18 years were vaccinated against COVID-19 (≥1 dose). Completed primary series vaccination was 44.2% among all children aged <18 years. By age group, completed primary series was 13.2% among children <5 years, 43.9% among children 5-11 years, and 63.3% among adolescents 12-17 years. Booster vaccination among those who completed the primary series was 39.1% among children 5-11 years and 55.3% among adolescents 12-17 years. Vaccination coverage differed by race/ethnicity, educational attainment, household income, region, parental COVID-19 vaccination status, prior COVID-19 diagnosis, child's age group, and parental age group. Parental reluctance was highest for children aged <5 years (46.8%). Main reasons for non-vaccination among reluctant parents were concerns about side effects (53.3%), lack of trust in COVID-19 vaccines (48.7%), and the belief that children do not need a COVID-19 vaccine (38.8%).

CONCLUSION

Disparities in COVID-19 vaccination coverage among children and adolescents continue to exist. Further efforts are needed to increase COVID-19 primary series and booster vaccination and parental confidence in vaccines.

Exclusive and dual influenza and COVID-19 vaccination among U.S. adults and adolescents in 2021

INTRODUCTION

Despite recommendations for influenza and COVID-19 vaccines, studies have documented gaps and disparities in vaccination coverage for adults and adolescents. Understanding the proportion and demographics of those unvaccinated against influenza and/or COVID-19 is important for tailoring appropriate messaging and strategies to increase confidence and uptake.

METHODS

Using the 2021 National Health Interview Survey (NHIS), we assessed the prevalence of four vaccination patterns (exclusive influenza vaccination, exclusive COVID-19 vaccination, dual influenza and COVID-19 vaccination, and neither vaccination) by sociodemographic and other characteristics among adults and adolescents 12-17 years. Adjusted multivariable regression analyses were conducted to examine factors associated with each of the four vaccination categories among adults and adolescents.

RESULTS

In 2021, 42.5% of adults and 28.3% of adolescents received both influenza and COVID-19 vaccines, while approximately a quarter (22.4%) of adults and a third (34.0%) of adolescents did not receive either vaccine. Among adults and adolescents, 6.0% and 11.4% were exclusively vaccinated against influenza and 29.1% and 26.4% were exclusively vaccinated against COVID-19, respectively. Among adults, exclusive COVID-19 or dual vaccination was more likely to be associated with older age, non-Hispanic multi/other race, and having a college degree compared to their respective counterparts. Exclusive influenza or neither vaccination was more likely to be associated with younger age, having a high school diploma or less, living below the poverty level, and having a previous COVID-19 diagnosis.

CONCLUSION

During the COVID-19 pandemic, approximately two-thirds of adolescents and three-fourths of adults received exclusive influenza or COVID-19 vaccines or both vaccines in 2021. Vaccination patterns differed by sociodemographic and other characteristics. Promoting confidence in vaccines and reducing barriers to access is needed to protect individuals and families from severe health consequences of vaccine-preventable diseases. Being up-to-date with all recommended vaccinations can prevent a future resurgence of hospitalizations and cases.Key messages42.5% of adults and 28.3% of adolescents received both influenza and COVID-19 vaccines in 2021, while approximately a quarter (22.4%) of adults and a third (34.0%) of adolescents did not receive either vaccine; 6.0% of adults and 11.4% of adolescents were exclusively vaccinated against influenza and 29.1% of adults and 26.4% of adolescents were exclusively vaccinated against COVID-19.Among adults, exclusive COVID-19 vaccination or dual vaccination was more likely to be associated with older age, non-Hispanic multi/other race, and having a college degree or higher compared to their respective counterparts; exclusive influenza vaccination or neither vaccination was more likely to be associated with younger age, having a high school diploma or less, living below poverty level, and having a previous COVID-19 diagnosis compared to their respective counterparts.Promoting confidence in vaccines and reducing barriers to access is needed to protect individuals and families from severe health consequences of vaccine-preventable diseases. Being up-to-date with all recommended vaccinations can prevent a future resurgence of hospitalizations and cases, especially as new variants emerge.

Moral foundations and HPV vaccine acceptance in the United States: State, parental, and individual factors

RATIONALE

Appeals to intuitive morality may present a novel approach to addressing vaccine hesitancy.

OBJECTIVE

To better understand the relationship between morality and vaccination by employing Moral Foundations Theory to studies surrounding the HPV vaccination at multiple different levels of decision making.

METHOD

We employed three different study modalities which examined moralities link to vaccination by employing Moral Foundations Theory. A state-wide ecological study aimed to understand population level trends. Two randomized control interventional studies were then created to understand the effects of Moral Foundations Theory based interventions on both parents of children and individual decision makers.

RESULTS

We demonstrated a negative association at the state level between the purity moral foundations and HPV vaccination rates (β = -.75, SE 0.23; p < .01) and a positive association between loyalty and HPV vaccination rates (β = 0.62 SE 0.24; p < .05). The parental study built upon this by demonstrating negative association between higher moral purity scores and attitudes towards the HPV vaccine and intention to vaccinate their children (β = -0.27 SE 0.07; p < .001). Our final study demonstrated a Moral Foundations Theory based intervention was associated with an increase in the odds of indicating an intention to receive the HPV vaccination (adjusted Odds Ratio (aOR) 2.59, 95% Confidence Interval (CI) 1.62-4.14). This equates to a 20% increase in the predicted probability of the intention to receive an HPV vaccine (39% CI (36%-42%) vs 60% CI (57%-63%).

CONCLUSIONS

Together, these studies demonstrate that moral foundations, specifically the purity foundation, appear to have a strong and consistent relationship with HPV vaccination. They also demonstrate the how moral values-based interventions may serve as a novel approach to increase HPV vaccine uptake with potential to be employed to target vaccine hesitancy more broadly.

Drivers of early childhood vaccination success in Nepal, Senegal, and Zambia: a multiple case study analysis using the Consolidated Framework for Implementation Research

INTRODUCTION

The fundamental components of a vaccine delivery system are well-documented, but robust evidence is needed on how the related processes and implementation strategies - including the facilitators and barriers - contribute to improvements in childhood vaccination coverage. The purpose of this study was to identify critical facilitators and barriers to the implementation of common interventions across three countries that have dramatically increased coverage of early childhood vaccination over the past 20 years, and to qualify common or divergent themes in their success.

METHODS

We conducted 278 key informant interviews and focus group discussions with public health leaders at the regional, district, and local levels and community members in Nepal, Senegal, and Zambia to identify intervention activities and the facilitators and barriers to implementation. We used thematic analysis grounded in the Consolidated Framework for Implementation Research (CFIR) constructs of inner and outer settings to identify immunization program key facilitators and barriers.

RESULTS

We found that the common facilitators to program implementation across the countries were the CFIR inner setting constructs of (1) networks and communications, (2) goals and feedback, (3) relative priority, and (4) readiness for implementation and outer setting constructs of (5) cosmopolitanism and (6) external policies and mandates. The common barriers were incentives and rewards, available resources, access to knowledge and information, and patients' needs and resources. Critical to the success of these national immunization programs were prioritization and codification of health as a human right, clear chain of command and shared ownership of immunization, communication of program goals and feedback, offering of incentives at multiple levels, training of staff central to vaccination education, the provision of resources to support the program, key partnerships and guidance on implementation and adoption of vaccination policies.

CONCLUSION

Adequate organizational commitment, resources, communication, training, and partnerships were the most critical facilitators for these countries to improve childhood vaccination.

Introduction to the special issue on vaccine hesitancy and refusal

This is an introduction to the special issue "Vaccine Hesitancy and Refusal." This special issue of Health Psychology examines various aspects of vaccine hesitancy using a health psychology lens. The timing of this issue, following a call for papers issued in the summer of 2021, in the midst of the COVID-19 pandemic, is reflected in the focus on COVID-19 vaccine hesitancy in the papers included here. This is important, as the field of vaccine hesitancy research has expanded greatly in response to the COVID-19 pandemic. As of March 2, 2023, a search of PubMed for "vaccine hesitancy" yielded 5,635 papers, dating back to 1968. A similar search for "COVID vaccine hesitancy" yielded 3,851 papers, starting in 2020. This highlights the need for new and novel theory-based interventions that can be broadly applicable to hesitancy to other routine vaccinations. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Critical interventions for demand generation in Zambia, Nepal, and Senegal with regards to the 5C psychological antecedents of vaccination

Introduction

Childhood vaccination is an effective intervention for lowering the burden of infectious disease. Vaccine coverage has increased globally, but vaccine hesitancy and refusal threatens these gains. The 5C psychological antecedents of vaccination ("5C") provides a validated measure of "vaccine hesitancy or confidence" to assess individual thoughts and behaviors behind vaccination. We investigated population-level factors that contributed to high and sustained vaccination coverage in Zambia, Nepal, and Senegal, and alignment with the 5Cs.

Methods

Data was collected in the larger Exemplars in Vaccine Delivery study, from focus group discussions (FDGs) and key informant interviews (KIIs) at the national, regional, district, health facility, and community levels of health systems in Zambia, Nepal, and Senegal. We assessed the demand environment, as relayed by participants, and identified interventions reported as successful for demand generation, then retroactively aligned the interventions with the 5C constructs.

Results

Demand was positively correlated with high confidence and collective responsibility. Psychological constraints sometimes impacted demand. Physical constraints created barriers in some communities, particularly difficult to access (i.e., mountainous). Occasionally, physical constraints did not affect vaccination behavior - parents believed the benefits of vaccination worth pursuing. Factors negatively correlated with demand and intent, complacency and calculation, had limited impact. Critical interventions were: targeted and tailored health education activities (media partnerships, school outreach); community engagement; community ownership; and community involvement (community health workers, leaders, religious figures).

Conclusion

We found similar interventions used to generate demand, with strategies aligned with the 5C constructs. Categorizing interventions by drivers of demand may help strategic planning and the division of resources; decision makers may choose to implement our suggested interventions. Assessing the 5Cs allows decision-makers to operationalize demand generation into concrete interventions and policies, and determine the individual impact of these constructs on the population and focus efforts on interventions tailored to a specific need.

Human papillomavirus vaccination at the first opportunity: An overview

The Advisory Committee on Immunization Practices (ACIP) has recommended human papillomavirus (HPV) vaccination for adolescents in the United States since 2006. Though recommended at a similar time to the routine recommendations for adolescent tetanus, diphtheria, and acellular pertussis vaccination (Tdap) and quadrivalent meningococcal vaccination (MCV4), HPV vaccine uptake has consistently lagged behind these other adolescent vaccines. The ACIP recommends HPV vaccination at 11-12 y, with vaccination starting at 9 y of age included as an option that is routinely encouraged by the American Academy of Pediatrics and American Cancer Society. To support efforts to increase HPV vaccination at the first opportunity, this commentary summarizes the current HPV vaccination recommendations and available evidence regarding HPV vaccination starting at 9 y - including recent studies and trials documenting the effectiveness of HPV vaccination at 9 in supporting vaccine series completion, while providing future directions for research and implementation to improve HPV vaccination.

Community-Centered Assessment to Inform Pandemic Response in Georgia (US)

The Georgia Community Engagement Alliance (CEAL) Against COVID-19 Disparities Project conducts community-engaged research and outreach to address misinformation and mistrust, to promote inclusion of diverse racial and ethnic populations in clinical trials and increase testing and vaccination uptake. Guided by its Community Coalition Board, The GEORGIA CEAL Survey was administered among Black and Latinx Georgia 18 years and older to learn about community knowledge, perceptions, understandings, and behaviors regarding COVID-19 testing and vaccines. Survey dissemination occurred using survey links generated through Qualtrics and disseminated among board members and other statewide networks. Characteristics of focus counties were (a) highest proportion of 18 years and older Black and Latinx residents; (b) lowest COVID-19 testing rates; and (c) highest SVI values. The final sample included 2082 surveyed respondents. The majority of participants were men (57.1%) and Latinx (62.8%). Approximately half of the sample was aged 18-30 (49.2%); the mean age of the sample was 33.2 years (SD = 9.0), ranging from 18 to 82 years of age. Trusted sources of COVID-19 information that significantly predicted the likelihood of vaccination included their doctor/health care provider (p-value: 0.0054), a clinic (p-value: 0.006), and university hospitals (p-value: 0.0024). Latinx/non-Latinx, Blacks vs. Latinx, Whites were significantly less likely to get tested and/or vaccinated. Non-Latinx, Blacks had higher mean knowledge scores than Latinx, Whites (12.1 vs. 10.9, p < 0.001) and Latinx, Blacks (12.1 vs. 9.6, respectively, p < 0.001). The mean knowledge score was significantly lower in men compared to women (10.3 vs. 11.0, p = 0.001), in those who had been previously tested for COVID-19 compared to those who had never been tested (10.5 vs. 11.5, respectively, p = 0.005), and in those who did not receive any dose of vaccination compared to those who were fully vaccinated (10.0 vs. 11.0, respectively, p < 0.001). These data provide a benchmark for future comparisons of the trajectory of public attitudes and practices related to the COVID-19 pandemic. They also point to the importance of tailoring communication strategies to specific cultural, racial, and ethnic groups to ensure that community-specific barriers to and determinants of health-seeking behaviors are appropriately addressed.

Understanding the Factors Influencing Health Care Provider Recommendations about Adolescent Vaccines: A Proposed Framework

Health care provider recommendations are among the most important factors influencing parents' decisions to vaccinate their adolescents. However, delivery of high-quality health care provider recommendations for vaccination is not universal. There is wide variation in the strength, timeliness and consistency of the delivery of recommendations for all adolescent vaccines. The factors that influence health care providers' recommendations are multi-level and can be conceptualized in much the same way as vaccine acceptance among parents. Health care providers are influenced by their own attitudes and beliefs about a vaccine and also by the patient they are treating and by the community in which they practice as well as state and national level vaccine policy. We propose a multi-level framework for understanding the factors that influence health care providers' recommendations at the individual, interpersonal and community level to both develop and adapt interventions to improve providers' recommendations.

Critical success factors for high routine immunization performance: A case study of Senegal

Background

The essential components of a vaccine delivery system are well-documented, but robust evidence is lacking on how policies and implementation strategies are operationalized to drive catalytic improvements in coverage. To address this gap, we identified success factors that supported improvements in routine immunization coverage in Senegal, especially from 2000 to 2019.

Methods

We identified Senegal as an exemplar in the delivery of childhood vaccines through analysis of DTP1 and DTP3 coverage data. Through interviews and focus group discussions at the national, regional, district, health facility, and community-level, we investigated factors that contributed to high and sustained vaccination coverage. We conducted a thematic analysis through application of implementation science frameworks to determine critical success factors. We triangulated these findings with quantitative analyses using publicly available data.

Results

The following success factors emerged: 1) Strong political will and prioritization of resources for immunization programming supported urgent allocation of funding and supplies; 2) Collaboration between the Ministry of Health and Social Action and external partners fostered innovation, capacity building, and efficiency; 3) Improved surveillance, monitoring, and evaluation allowed for timely and evidence-based decision making; 4) Community ownership of vaccine service delivery supported tailored programming and response to local needs; and 5) Community health workers spearheaded vaccine promotion and demand generation for vaccines.

Conclusion

The vaccination program in Senegal was supported by evidence-based decision making at the national-level, alignment of priorities between governmental entities and external partners, and strong community engagement initiatives that fostered local ownership of vaccine delivery and uptake. High routine immunization coverage was likely driven by prioritization of immunization programming, improved surveillance systems, a mature and reliable community health worker program, and tailored strategies for addressing geographical, social, and cultural barriers.

Exploring celebrity influence on public attitude towards the COVID-19 pandemic: social media shared sentiment analysis

OBJECTIVES

The COVID-19 pandemic has introduced new opportunities for health communication, including an increase in the public's use of online outlets for health-related emotions. People have turned to social media networks to share sentiments related to the impacts of the COVID-19 pandemic. In this paper, we examine the role of social messaging shared by Persons in the Public Eye (ie, athletes, politicians, news personnel, etc) in determining overall public discourse direction.

METHODS

We harvested approximately 13 million tweets ranging from 1 January 2020 to 1 March 2022. The sentiment was calculated for each tweet using a fine-tuned DistilRoBERTa model, which was used to compare COVID-19 vaccine-related Twitter posts (tweets) that co-occurred with mentions of People in the Public Eye.

RESULTS

Our findings suggest the presence of consistent patterns of emotional content co-occurring with messaging shared by Persons in the Public Eye for the first 2 years of the COVID-19 pandemic influenced public opinion and largely stimulated online public discourse.

DISCUSSION

We demonstrate that as the pandemic progressed, public sentiment shared on social networks was shaped by risk perceptions, political ideologies and health-protective behaviours shared by Persons in the Public Eye, often in a negative light.

CONCLUSION

We argue that further analysis of public response to various emotions shared by Persons in the Public Eye could provide insight into the role of social media shared sentiment in disease prevention, control and containment for COVID-19 and in response to future disease outbreaks.

Trends in vaccination schedules and up-to-date status of children 19-35 months, United States, 2015-2020

OBJECTIVES

To estimate trends in, and factors associated with, vaccination patterns and up-to-date immunization status of U.S. children by 19 to 35 months of age.

METHODS

Data from the 2015 to 2020 National Immunization Surveys were used to assess trends in vaccination patterns, up-to-date status, and zero vaccination status of U.S. children by 19-35 months. Vaccination patterns were categorized as: 1) recommended, 2) alternate, or 3) unknown or unclassifiable. Multivariable analyses were conducted to examine factors associated with each vaccination pattern and up-to-date status for all recommended vaccines.

RESULTS

From 2015 to 2020, the proportion of U.S. children completing the recommended schedule increased from 62.5% to 69.4%, alternative schedule decreased from 21.6% to 16.2%, and unknown or unclassifiable schedules decreased from 15.9% to 14.3%. In addition, being not up-to-date decreased from 39.7% to 35.6%. There was no change in the percentage of children receiving zero vaccinations from 2015 to 2020 (0.9% to 0.9%). Respondents with lower household income or who were uninsured were more likely to follow an alternate or unknown/unclassifiable schedule, or not be up-to-date with vaccines.

CONCLUSION

Following any schedule other than the recommended schedule was associated with not being up-to-date on immunizations. Increased efforts to catch up on recommended vaccines is important for protecting children's health. Further efforts should be made to improve timely adherence to recommended vaccination schedules, particularly among populations with the largest disparities in coverage through a tailored approach to increase confidence in and access to vaccines.

Barriers and supports for uptake of human papillomavirus vaccination in Indigenous people globally: A systematic review

Despite the availability of effective and safe human papillomavirus (HPV) vaccines that reduce the incidence and impact of cervical cancer and other cancers, HPV vaccine coverage rates remain persistently low and the cervical cancer burden disproportionately high among Indigenous people globally. This study aimed to systematically identify, appraise, and summarize the literature on documented barriers and supports to HPV vaccination in Indigenous populations internationally. Forty-three studies were included and an inductive, qualitative, thematic synthesis was applied. We report on 10 barrier themes and 7 support themes to vaccine uptake, and provide a quantitative summary of metrics. Focusing on Indigenous perspectives reported in the literature, we propose recommendations on community-research collaboration, culturally safe intergenerational and gender-equitable community HPV vaccine education, as well as multi-level transparency to ensure informed consent is secured in the context of reciprocal relationships. Although the voices of key informant groups (e.g., HPV-vaccine eligible youth and community Elders) are underrepresented in the literature, the identification of barriers and supports to HPV vaccination in a global Indigenous context might help inform researchers and health policy makers who aim to improve HPV vaccine uptake in Indigenous populations.

Vaccine Attitudes and COVID-19 Vaccine Intention Among Parents of Children With Kidney Disease or Primary Hypertension

RATIONALE & OBJECTIVE

Children with kidney disease and primary hypertension may be more vulnerable to COVID-19. We examined COVID-19 vaccine hesitancy among parents of children with chronic kidney disease or hypertension.

STUDY DESIGN

Sequential explanatory mixed-methods design; survey followed by in-depth interviews.

SETTING & PARTICIPANTS

Parents of children aged <18 years with kidney disease or primary hypertension within a large pediatric practice.

EXPOSURE

Parental attitudes toward general childhood and influenza vaccines assessed by the Vaccine Hesitancy Scale. Kidney disease classification, demographic and socioeconomic factors, experiences with COVID-19, COVID-19 mitigation activities and self-efficacy, and sources of vaccine information.

OUTCOME

Willingness to vaccinate child against COVID-19.

ANALYTICAL APPROACH

Analysis of variance (ANOVA) test to compare parental attitudes toward general childhood and influenza vaccination with attitudes toward COVID-19 vaccination. Multinomial logistic regression to assess predictors of willingness to vaccinate against COVID-19. Thematic analysis of interview data to characterize influences on parental attitudes.

RESULTS

Of the participants, 207 parents completed the survey (39% of approached): 75 (36%) were willing, 80 (39%) unsure, and 52 (25%) unwilling to vaccinate their child against COVID-19. Hesitancy toward general childhood and influenza vaccines was highest among the unwilling group (P < 0.001). More highly educated parents more likely to be willing to vaccinate their children, while Black race was associated with being more likely to be unwilling. Rushed COVID-19 vaccine development as well as fear of serious and unknown long-term side effects were themes that differed across the parental groups that were willing, unsure, or unwilling to vaccinate their children. Although doctors and health care teams are trusted sources of vaccine information, perceptions of benefit versus harm and experiences with doctors differed among these 3 groups. The need for additional information on COVID-19 vaccines was greatest among those unwilling or unsure about vaccinating.

LIMITATIONS

Generalizability may be limited.

CONCLUSIONS

Two-thirds of parents of children with kidney disease or hypertension were unsure or unwilling to vaccinate their child against COVID-19. Higher hesitancy toward routine childhood and influenza vaccination was associated with hesitancy toward COVID-19 vaccines. Enhanced communication of vaccine information relevant to kidney patients in an accessible manner should be examined as a means to reduce vaccine hesitancy.

PLAIN-LANGUAGE SUMMARY

Children with kidney disease or hypertension may do worse with COVID-19. As there are now effective vaccines to protect children from COVID-19, we wanted to find out what parents think about COVID-19 vaccines and what influences their attitudes. We surveyed and then interviewed parents of children who had received a kidney transplant, were receiving maintenance dialysis, had chronic kidney disease, or had hypertension. We found that two-thirds of parents were hesitant to vaccinate their children. Their reasons varied, but the key issues included the need for information pertinent to their child and a consistent message from doctors and other health care providers. These findings may inform an effective vaccine campaign to protect children with kidney disease and hypertension.

Critical success factors for high routine immunization performance: A case study of Nepal

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Nepal reported high and sustained immunization coverage compared to peers.

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National and multi-national partnerships supported information sharing, division of labor, and mutual capacity building.

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Pro-vaccine messaging through various mediums, including Female Community Health Volunteers, which was tailored to local needs, generated public awareness.

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Cultural values fostered collective responsibility and community ownership of vaccine coverage.

Introduction

The essential components of a vaccine delivery system are well-documented, but robust evidence on how and why the related processes and implementation strategies drive catalytic improvements in vaccination coverage are not well established. To address this gap, we identified critical success factors that may have led to substantial improvements in routine childhood immunization coverage in Nepal from 2000 through 2019.

Methods

We identified Nepal as an exemplar in the delivery of early childhood immunization through analysis of DTP1 and DTP3 coverage data. Through interviews and focus group discussions at the national, regional, district, health post, and community level, we investigated factors that contributed to high and sustained vaccine coverage. We conducted a thematic analysis through application of implementation science frameworks to determine critical success factors. We triangulated these findings with quantitative analyses using publicly available data.

Results

The following success factors emerged: 1) Codification of health as a human right, - along with other vaccine-specific legislation - ensured the stability of vaccination programming; 2) National and multi-national partnerships supported information sharing, division of labor, and mutual capacity building; 3) Pro-vaccine messaging through various mediums, which was tailored to local needs, generated public awareness; 4) Female Community Health Volunteers educated community members as trusted and compassionate neighbors; and 5) Cultural values fostered collective responsibility and community ownership of vaccine coverage.

Conclusion

This case study of Nepal suggests that the success of its national immunization program relied on the engagement and understanding of the beneficiaries. The immunization program was supported by consistent and reliable commitment, collaboration, awareness, and collective responsibility between the government, community, and partners. These networks are strengthened through a collective dedication to vaccination programming and a universal belief in health as a human right.

MomsTalkShots, tailored educational app, improves vaccine attitudes: a randomized controlled trial

BACKGROUND

Many pregnant women and parents have concerns about vaccines. This analysis examined the impact of MomsTalkShots, an individually tailored educational application, on vaccine attitudes of pregnant women and mothers.

METHODS

MomsTalkShots was the patient-level component of a multi-level intervention to improve maternal and infant vaccine uptake that also included provider- and practice-level interventions. The impact of these interventions was studied using a two-by-two factorial design, randomizing at both the patient- and the practice-level. Study staff recruited pregnant women from a diverse set of prenatal care practices in Colorado and Georgia between June 2017 and July 2018. All participants (n = 2087) received a baseline survey of maternal and infant vaccine intentions and attitudes, and two follow-up surveys at least 1 month and 1 year after their infant's birth, respectively. Half of participants (n = 1041) were randomly assigned to receive educational videos through MomsTalkShots, algorithmically tailored to their vaccine intentions, attitudes, and demographics. Since the practice/provider intervention did not appear impactful, this analysis focused on MomsTalkShots regardless of the practice/provider intervention.

RESULTS

By 1 month post-birth, MomsTalkShots increased perceived risk of maternal influenza disease (61% among MomsTalkShots recipients vs 55% among controls; Odds Ratio: 1.61, 95% Confidence Interval: 1.23-2.09), confidence in influenza vaccine efficacy (73% vs 63%; OR: 1.97, 95%CI: 1.47-2.65), and perceived vaccine knowledge (55% vs 48%; OR: 1.39, 95%CI: 1.13-1.72). Among those intending not to vaccinate at baseline, MomsTalkShots increased perceived risk of maternal influenza disease (38% vs 32%; OR: 2.07, 95%CI: 1.15-3.71) and confidence in influenza vaccine efficacy (44% vs 28%; OR: 2.62, 95%CI: 1.46-4.69). By 1 year post-birth, MomsTalkShots increased perceived vaccine knowledge (62% vs 50%; OR: 1.74, 95%CI: 1.36-2.24) and trust in vaccine information from obstetricians and pediatricians (64% vs 55%; OR: 1.53, 95%CI: 1.17-2.00). Among those uncertain about vaccinating at baseline, MomsTalkShots increased perceived vaccine knowledge (47% vs 12%; OR: 6.89, 95%CI: 1.52-31.25) and reduced infant vaccine safety concerns (71% vs 91%; OR: 0.24, 95%CI: 0.06-0.98).

CONCLUSIONS

MomsTalkShots improved pregnant women's and mothers' knowledge and perceptions of maternal and infant vaccines and the diseases they prevent, and offers a scalable tool to address vaccine hesitancy.

TRIAL REGISTRATION

Registered at Clinicaltrials.gov on 13/09/2016 (registration number: NCT02898688).

Healthcare professionals' perceptions and recommendations regarding adolescent vaccinations in Georgia and Tennessee during the COVID-19 pandemic: A qualitative research

INTRODUCTION

Despite its benefits, HPV vaccine uptake has been historically lower than other recommended adolescent vaccines in the United States (US). While hesitancy and misinformation have threatened vaccinations for many years, the adverse impacts from COVID-19 pandemic on preventive services have been far-reaching.

OBJECTIVES

To explore the perceptions and experiences of adolescent healthcare providers regarding routine vaccination services during the COVID-19 pandemic.

METHODOLOGY

Between December 2020 and May 2021, in-depth qualitative interviews were conducted via Zoom video conferencing among a purposively selected, diverse group of adolescent healthcare providers (n = 16) within 5 healthcare practices in the US southeastern states of Georgia and Tennessee. Audio recordings were transcribed verbatim and analyzed using a rapid qualitative analysis framework. Our analysis was guided by the grounded theory and inductive approach.

RESULTS

Participants reported that patient-provider communications; effective use of presumptive languaging; provider's continuing education/training; periodic reminders/recall messages; provider's personal conviction on vaccine safety/efficacy; early initiation of HPV vaccination series at 9 years; community partnerships with community health navigators/vaccine champions/vaccine advocates; use of standardized forms/prewritten scripts/standard operating protocols for patient-provider interactions; and vaccine promotion through social media, brochures/posters/pamphlets as well as outreaches to schools and churches served as facilitators to adolescent HPV vaccine uptake. Preventive adolescent services were adversely impacted by the COVID-19 pandemic at all practices. Participants highlighted an initial decrease in patients due to the pandemic, while some practices avoided the distribution of vaccine informational materials due to sanitary concerns.

CONCLUSION

As part of a larger study, we provided contextual information to refine an intervention package currently being developed to improve adolescent preventive care provision in healthcare practices. Our results could inform the implementation of comprehensive intervention strategies that improve HPV vaccination rates. Additionally, lessons learned (e.g. optimizing patient- provider interactions) could be adopted to expand COVID-19 vaccine acceptance on a sizable scale.

Fine-Tuned Sentiment Analysis of COVID-19 Vaccine Related Social Media Data: A Comparative Study

Background

The emergence of the novel coronavirus (COVID-19) and the necessary separation of populations have led to an unprecedented number of new social media users seeking information related to the pandemic. Currently, with an estimated 4.5 billion users worldwide, social media data offer an opportunity for near real-time analysis of large bodies of text related to disease outbreaks and vaccination. These analyses can be used by officials to develop appropriate public health messaging, digital interventions, educational materials, and policies.

Objective

Our study investigated and compared public sentiment related to COVID-19 vaccines expressed on 2 popular social media platforms—Reddit and Twitter—harvested from January 1, 2020, to March 1, 2022.

Methods

To accomplish this task, we created a fine-tuned DistilRoBERTa model to predict the sentiments of approximately 9.5 million tweets and 70 thousand Reddit comments. To fine-tune our model, our team manually labeled the sentiment of 3600 tweets and then augmented our data set through back-translation. Text sentiment for each social media platform was then classified with our fine-tuned model using Python programming language and the Hugging Face sentiment analysis pipeline.

Results

Our results determined that the average sentiment expressed on Twitter was more negative (5,215,830/9,518,270, 54.8%) than positive, and the sentiment expressed on Reddit was more positive (42,316/67,962, 62.3%) than negative. Although the average sentiment was found to vary between these social media platforms, both platforms displayed similar behavior related to the sentiment shared at key vaccine-related developments during the pandemic.

Conclusions

Considering this similar trend in shared sentiment demonstrated across social media platforms, Twitter and Reddit continue to be valuable data sources that public health officials can use to strengthen vaccine confidence and combat misinformation. As the spread of misinformation poses a range of psychological and psychosocial risks (anxiety and fear, etc), there is an urgency in understanding the public perspective and attitude toward shared falsities. Comprehensive educational delivery systems tailored to a population’s expressed sentiments that facilitate digital literacy, health information–seeking behavior, and precision health promotion could aid in clarifying such misinformation.

Multi-tiered intervention to increase maternal immunization coverage: A randomized, controlled trial

OBJECTIVE

To evaluate the impact of a multi-component intervention package of maternal immunization uptake in obstetric care clinics.

METHODS

In a multi-level, cluster- and individually-randomized controlled trial we implemented an evidence-based intervention that targeted practice-, provider- and patient-level barriers to vaccine uptake. Obstetric practices were randomized to receive the practice and provider-level interventions or continue their normal standard of care. We enrolled pregnant women at practices in Georgia and Colorado and randomized women into patient-level intervention and control groups, resulting in four study arms. The primary outcomes were receipt of the influenza and tetanus, diphtheria and acellular pertussis (Tdap) vaccines during pregnancy. A sample size of 550 women per arm (2200 total) was planned and enrolled to compare the intervention between the four study arms.

RESULTS

Between June 2017 and July 2018, 4907 women were screened and 2200 women were randomized, 550 to each of the four study arms. We were unable to follow-up with 108 women, for a final sample size of 2092. Sample characteristics and sample size were similar among study arms. There was no significant increase in Tdap or influenza vaccine uptake overall. Among women who had no intention of or were unsure about receiving the influenza vaccine during pregnancy, those who received just the patient-level intervention were 61% more likely to receive the influenza vaccine than those in the control arm (Relative risk: 1.61; 95% Confidence Interval: 1.18-2.21). There was no significant difference in vaccine uptake for either influenza or tetanus, diphtheria and acellular pertussis between the four arms of the study.

CONCLUSIONS

This trial highlights the need for more targeted interventions to improve vaccine uptake. Future work should focus on clinics with low baseline vaccine uptake and the patient-level intervention should be expanded and targeted towards women with low vaccine confidence.

Critical success factors for routine immunization performance: A case study of Zambia 2000 to 2018

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This paper describes how policies and programs contributed to improved vaccine coverage in Zambia.

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Communication, coordination, and collaboration between implementing levels were imperative.

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Adjacent successes in health systems strengthening and governance were leveraged.

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Policies in Zambia include flexibility in implementation for tailored approaches in each district.

Introduction

The essential components of a vaccine delivery system are well-documented, but robust evidence on how and why the related processes and implementation strategies prove effective at driving coverage is not well-established. To address this gap, we identified critical success factors associated with advancing key policies and programs that may have led to the substantial changes in routine childhood immunization coverage in Zambia between 2000 and 2018.

Methods

We identified Zambia as an exemplar in the delivery of childhood vaccines through analysis of DTP1 and DTP3 coverage data. Through interviews and focus group discussions at the national and subnational levels, we investigated factors that contributed to high and sustained vaccination coverage. We conducted a thematic analysis through application of implementation science frameworks to determine critical success factors. We triangulated these findings with quantitative analyses using publicly available data.

Results

The following success factors emerged: 1) the Inter-agency Coordinating Committee was strengthened for long-term engagement which, complemented by the Zambia Immunization Technical Advisory Group, is valued by the government and integrated into national-level decision-making; 2) the Ministry of Health improved the coordination of data collection and review for informed decision-making across all levels; 3) Regional multi-actor committees identified development priorities, strategies, and funding, and iteratively adjusted policies to account for facilitators, barriers, and lessons learned; 4) Vaccine messaging was disseminated through multiple channels, including the media and community leaders, increasing trust in the government by community members; 5) The Zambia Ministry of Health and Churches Health Association of Zambia formalized a long-term organizational relationship to leverage the strengths of faith-based organizations; and 6) Neighborhood Health Committees spearheaded community-driven strategies via community action planning and ultimately strengthened the link between communities and health facilities.

Conclusion

Broader health systems strengthening and strong partnerships between various levels of the government, communities, and external organizations were critical factors that accelerated vaccine coverage in Zambia. These partnerships were leveraged to strengthen the overall health system and healthcare governance.

Estimating the number of US children susceptible to measles resulting from COVID-19-related vaccination coverage declines

Measles elimination hinges on vaccination coverage remaining above 95% to retain sufficient community protection. Recent declines in routine measles vaccinations due to the COVID-19 pandemic coupled with prior models indicating the country was close to the 92% herd immunity benchmark are a cause for concern. We evaluated population-level measles susceptibility in the US, including sensitivity analyses accounting for pandemic-related impacts on immunization. We estimated the number of children aged 0–18 currently susceptible to measles and modeled susceptibility proportions in decreased vaccination scenarios. Participants were respondents to the NIS-Teen survey between 2008 and 2017 that also had provider-verified vaccination documentation. The exposure of interest was vaccination with a measles-containing vaccine (MCV), and the age at which they were vaccinated for all doses given. Using age at vaccination, we estimated age-based probabilities of vaccination and modeled population levels of MCV immunization and immunity vs. susceptibility. Currently, 9,145,026 children (13.1%) are estimated to be susceptible to measles. With pandemic level vaccination rates, 15,165,221 children (21.7%) will be susceptible to measles if no attempt at catch-up is made, or 9,454,436 children (13.5%) if catch-up vaccinations mitigate the decline by 2–3%. Models based on increased vaccine hesitancy also show increased susceptibility at national levels, with a 10% increase in hesitancy nationally resulting in 14,925,481 children (21.37%) susceptible to measles, irrespective of pandemic vaccination levels. Current levels of measles immunity remain below herd immunity thresholds. If pandemic-era reductions in childhood immunization are not rectified, population-level immunity to measles is likely to decline further.

Caregivers of Adolescents' Motivators and Barriers to Vaccinating Children Against Human Papillomavirus

In the United States (US), acceptance of adolescent vaccines, as measured by vaccine uptake in adolescents, is high amongst caregivers. However, this does not routinely extend to Human Papillomavirus (HPV) vaccination. In the US state of Georgia, HPV vaccine coverage rates remain suboptimal, especially when compared to other adolescent vaccines. Our study aims to identify and examine caregivers' motivators and barriers towards vaccinating their adolescents against HPV. We conducted nine focus groups with caregivers (n = 75) throughout the state. Using MAXQDA for thematic analysis, we identified common motivators and barriers related to adolescent HPV vaccine uptake amongst caregivers. Barriers reported include caregivers' inability to develop a trusting patient-provider relationship and HPV vaccine message framing issues. Motivators reported include caregivers' intrinsic need to protect their adolescents and trust their healthcare provider. Trust in healthcare providers was a key theme identified towards mitigating barriers and reinforcing motivators related to HPV vaccine acceptance and uptake. By improving patient-provider relationships throughout Georgia and streamlining digestible, representative vaccine information sharing across reputable sources, caregivers may become more receptive to vaccinating their adolescents.

Exemplars in vaccine delivery protocol: a case-study-based identification and evaluation of critical factors in achieving high and sustained childhood immunisation coverage in selected low-income and lower-middle-income countries

INTRODUCTION

Increases in global childhood vaccine delivery have led to decreases in morbidity from vaccine-preventable diseases. However, these improvements in vaccination have been heterogeneous, with some countries demonstrating greater levels of change and sustainability. Understanding what these high-performing countries have done differently and how their decision-making processes will support targeted improvements in childhood vaccine delivery.

METHODS AND ANALYSIS

We studied three countries-Nepal, Senegal, Zambia-with exemplary improvements in coverage between 2000 and 2018 as part of the Exemplars in Global Health Programme. We apply established implementation science frameworks to understand the 'how' and 'why' underlying improvements in vaccine delivery and coverage. Through mixed-methods research, we will identify drivers of catalytic change in vaccine coverage and the decision-making process supporting these interventions and activities. Methods include quantitative analysis of available datasets and in-depth interviews and focus groups with key stakeholders in the global, national and subnational government and non-governmental organisation space, as well as community members and local health delivery system personnel.

ETHICS AND DISSEMINATION

Working as a multinational and multidisciplinary team, and under oversight from all partner and national-level (where applicable) institutional review boards, we collect data from participants who provided informed consent. Findings are disseminated through a variety of forms, including peer-reviewed manuscripts related to country-specific case studies and vaccine system domain-specific analyses, presentations to key stakeholders in the global vaccine delivery space and narrative dissemination on the Exemplars.Health website.

The Efficacy of a Smartphone Game to Prevent HIV Among Young Africans: Protocol for a Randomized Controlled Trial in the Context of COVID-19

BACKGROUND

Adolescents contribute slightly less than one-third of all new HIV infections in sub-Saharan Africa. There is a need for more effective intervention approaches to help young adolescents safely navigate through adolescence and into adulthood. We are assessing the efficacy of Tumaini, a smartphone game designed to prevent HIV among young Africans. Against the background of COVID-19, meaningful alteration of the research protocol was necessary to ensure successful implementation and retention of the study participants in ongoing research.

OBJECTIVE

The objective of our protocol is to determine (1) if Tumaini delays sexual debut and increases condom use at first sex and (2) whether it influences behavioral mediators of early and unprotected sex.

METHODS

Participants were recruited from Kisumu County in Western Kenya. This study is a 2-arm, individual-randomized controlled trial that enrolled 1004 adolescents aged between 12 years and 15 years. The intervention arm participants are playing Tumaini, while the control arm is provided with Brainilis, a commercially available control game. The study period will last 45 months. At baseline, participants in both arms completed a baseline survey and biological testing for HIV and herpes simplex virus, type 2 (HSV-2); participants will have annual game play periods in years 1-3. They will also complete a total of 12 follow-up surveys. At endline, repeat biological testing will be conducted. Protocol adaptations were necessitated by the COVID-19 pandemic and implemented in accordance with local public health guidelines.

RESULTS

Participants were enrolled between October 2020 and November 2020. We plan to complete study procedures in September 2024. The enrolled participant sample was 50.1% (499/996) female and had a mean age of 14.0 (SD 0.6) years.

CONCLUSIONS

This ongoing research demonstrates that, with appropriate revisions to planned protocol activities guided by the need to maintain study integrity, protect both study participants and staff, and adhere to institutional review board and local health authority guidelines, human subject research is possible in the context of a global pandemic. If the trial demonstrates efficacy, Tumaini would provide an alternative, remote means of delivering age-appropriate education to adolescents on safer sex, HIV prevention, and effective life skills on a highly scalable, low-cost, and culturally adaptable platform.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04437667; https://clinicaltrials.gov/ct2/show/NCT04437667.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/35117.

U.S. Vietnamese parents' HPV vaccine decision-making for their adolescents: an exploration of practice-, provider-, and patient-level influences

U.S. Vietnamese have high cervical cancer incidence and low human papillomavirus (HPV) vaccine initiation. Using the P3 model, we explored practice-, provider-, and patient-level determinants of U.S. Vietnamese parents’ HPV vaccine decision-making for their adolescents. We conducted a cross-sectional, online survey (04/2020–12/2020) with U.S. Vietnamese parents who had ≥ 1 adolescent ages 9–18. We assessed HPV vaccination outcomes (initiation, willingness to initiate, completion) and provider recommendation. Modified Poisson regressions were used to identify practice-, provider- and patient-level correlates of outcomes. The sample (n = 408) was 44 years old on average; 83% were female and 85% had a Bachelor’s degree. Around half of adolescents were female (51%) and 13–18 year old (54%). Only 41 and 23% of parents had initiated and completed the HPV vaccine series for their child, respectively. Initiation was associated with receiving provider recommendation (either low- or high-quality), while willingness to initiate was associated with receiving high-quality recommendation. Both initiation and willingness to initiate was negatively associated with parental perception that their child was too young for a “sexually transmitted infection (STI)-preventing vaccine.” Provider recommendation was associated with higher parental U.S. acculturation and the child being older and female. Provider-facing interventions should promote high-quality, age-based, gender-neutral HPV vaccine recommendation. These and population- and individual-facing interventions should recognize the need for additional parental education, particularly related to misconceptions regarding STI prevention.

A Digital Personal Health Library for Enabling Precision Health Promotion to Prevent Human Papilloma Virus-Associated Cancers

Human papillomavirus (HPV) causes the most prevalent sexually transmitted infection (STI) in the United States. Sexually active young adults are susceptible to HPV, accounting for approximately 50% of new STIs. Oncogenic HPV subtypes 16 and 18 are associated with squamous intraepithelial lesions and cancers and are mostly preventable through prophylactic HPV vaccination. Accordingly, this study's objectives are to (1) summarize SDoH barriers and implication for low HPV vaccination rates among young adults (18-26 years), (2) propose a digital health solution that utilizes the PHL to collect, integrate, and manage personalized sexual and health information, and (3) describe the features of the PHL-based app. Through the application of novel techniques from artificial intelligence, specifically knowledge representation, semantic web, and natural language processing, this proposed PHL-based application will compile clinical, biomedical, and SDoH data from multi-dimensional sources. Therefore, this application will provide digital health interventions that are customized to individuals' specific needs and capacities. The PHL-based application could promote management and usage of personalized digital health information to facilitate precision health promotion thereby, informing health decision-making regarding HPV vaccinations, routine HPV/STI testing, cancer screenings, vaccine safety/efficacy/side effects, and safe sexual practices. In addition to detecting vaccine hesitancy, disparities and perceived barriers, this application could address participants' specific needs/challenges with navigating health literacy, technical skills, peer influence, education, language, cultural and spiritual beliefs. Precision health promotion focused on improving knowledge acquisition and information-seeking behaviors, promoting safe sexual practices, increasing HPV vaccinations, and facilitating cancer screenings could be effective in preventing HPV-associated cancers.

Prevalence of human papillomavirus among females older than recommended age for vaccination by birth cohort, United States 2003‒2016

BACKGROUND

Apparent associations between HPV prevalence and age observed in cross-sectional studies could be misleading if cohort effects influence HPV detection.

METHODS

Using data from 2003-2016 National Health and Nutrition Examination Surveys (NHANES), we evaluated overall and 10-year birth cohort-specific cervicovaginal HPV prevalence estimates (any, high-risk [HR], and non-HR) by 3-year age group among 27-59 year-old females born in 1950-1979. Average percent changes (APC) in HPV prevalence by 3-year age were calculated using prevalence ratios from log-binomial models.

RESULTS

Overall, prevalence of any HPV declined from 49.9% in 27-29 year-olds to 33.8% in 57-59 year-olds [APC: -2.82% per 3-year age group, 95% confidence interval (CI): -4.02%, -1.60%] as did prevalence of HR-HPV [APC: -6.19% (95% CI: -8.09%, -4.26%)] and non-HR-HPV [APC: -2.00% (95% CI: -3.48%, -0.51%)]. By birth cohort, declines by age group were seen in prevalences of any HPV, HR-HPV, and non-HR-HPV for those born in the 1950s and 1970s and in any HPV and HR-HPV for those born in the 1960s (APC range: -14.08% - 0.06%).

CONCLUSIONS

Declines in HPV prevalence with age in these cross-sectional surveys cannot be explained by birth cohort differences alone, as associations were observed across all birth cohorts. These findings are consistent with biological and behavioral explanations.

A framework for identifying and learning from countries that demonstrated exemplary performance in improving health outcomes and systems

This paper introduces a framework for conducting and disseminating mixed methods research on positive outlier countries that successfully improved their health outcomes and systems. We provide guidance on identifying exemplar countries, assembling multidisciplinary teams, collecting and synthesising pre-existing evidence, undertaking qualitative and quantitative analyses, and preparing dissemination products for various target audiences. Through a range of ongoing research studies, we illustrate application of each step of the framework while highlighting key considerations and lessons learnt. We hope uptake of this comprehensive framework by diverse stakeholders will increase the availability and utilisation of rigorous and comparable insights from global health success stories.

Influenza Vaccination Rates Among Patients With a History of Cancer: Analysis of the National Health Interview Survey

Background

Annual influenza vaccination is recommended for all patients with cancer, but vaccine uptake data by cancer type and time since diagnosis are limited. We sought to estimate vaccination rates across different cancer types in the United States and determine whether rates vary over time since diagnosis.

Methods

Vaccination rates in individuals with solid tumor and hematological malignancies were estimated using data from 59 917 individuals obtained by the 2016 and 2017 National Health Interview Survey conducted by the Centers for Disease Control and Prevention.

Results

An average of 64% of the 5053 individuals with self-reported cancer received the influenza vaccine. Vaccination rates in men and women with solid tumors (66.6% and 60.3%, respectively) and hematological malignancies (58.1% and 59.2%, respectively) were significantly higher compared to those without cancer (38.9% and 46.8%, respectively). Lower rates were seen in uninsured patients, those younger than 45 years of age, and in African Americans with hematological malignancies but not with solid tumors. Vaccine uptake was similar regardless of time since cancer diagnosis.

Conclusions

Influenza vaccination rates are higher in men and women with cancer but remain suboptimal, highlighting the need for additional measures to improve vaccine compliance and prevent complications from influenza across all cancer types.

Adolescent Consent for Human Papillomavirus Vaccine: Ethical, Legal, and Practical Considerations

We address ethical, legal, and practical issues related to adolescent self-consent for human papillomavirus (HPV) vaccination. HPV vaccination coverage continues to lag well behind the national goal of 80% series completion. Structural and behavioral interventions have improved vaccination rates, but attitudinal, behavioral, and access barriers remain. A potential approach for increasing access and improving vaccination coverage would be to permit adolescents to consent to HPV vaccination for themselves. We argue that adolescent self-consent is ethical, but that there are legal hurdles to be overcome in many states. In jurisdictions where self-consent is legal, there can still be barriers due to lack of awareness of the policy among healthcare providers and adolescents. Other barriers to implementation of self-consent include resistance from antivaccine and parent rights activists, reluctance of providers to agree to vaccinate even when self-consent is legally supported, and threats to confidentiality. Confidentiality can be undermined when an adolescent's self-consented HPV vaccination appears in an explanation of benefits communication sent to a parent or if a parent accesses an adolescent's vaccination record via state immunization information systems. In the context of the COVID-19 pandemic, which has led to a substantial drop in HPV vaccination, there may be even more reason to consider self-consent. The atmosphere of uncertainty and distrust surrounding future COVID-19 vaccines underscores the need for any vaccine policy change to be pursued with clear communication and consistent with ethical principles.

Addressing Parental Vaccine Hesitancy and Other Barriers to Childhood/Adolescent Vaccination Uptake During the Coronavirus (COVID-19) Pandemic

Routine childhood immunizations are proven to be one of the most effective public health interventions at controlling numerous deadly diseases. Therefore, the CDC recommends routine immunizations for children and adolescent populations against vaccine-preventable diseases e.g., tetanus, pertussis, diphtheria, etc. This current review sought to examine barriers to pediatric vaccine uptake behaviors during the COVID-19 pandemic. We also explored the implications for parental vaccine hesitancy/delay during an ongoing health crisis and proposed recommendations for increasing vaccine confidence and compliance. Our review determined that the receipt for vaccinations steadily improved in the last decade for both the United States and Tennessee. However, this incremental progress has been forestalled by the COVID-19 pandemic and other barriers i.e. parental vaccine hesitancy, social determinants of health (SDoH) inequalities, etc. which further exacerbate vaccination disparities. Moreover, non-compliance to routine vaccinations could cause an outbreak of diseases, thereby, worsening the ongoing health crisis and already strained health care system. Healthcare providers are uniquely positioned to offer effective recommendations with presumptive languaging to increase vaccination rates, as well as, address parental vaccine hesitancy. Best practices that incorporate healthcare providers' quality improvement coaching, vaccination reminder recall systems, adherence to standardized safety protocols (physical distancing, hand hygiene practices, etc.), as well as, offer telehealth and outdoor/drive-through/curbside vaccination services, etc. are warranted. Additionally, a concerted effort should be made to utilize public health surveillance systems to collect, analyze, and interpret data, thereby, ensuring the dissemination of timely, accurate health information for effective health policy decision-making e.g., vaccine distribution, etc.

Demographic benchmarks for equitable coverage of the COVID-19 vaccination program among priority populations

We report the demographic distribution of non-institutionalized populations in the US who are prioritized for COVID-19 vaccination by ethnicity, age and sex and region. The composition of non-institutionalized priority populations was estimated using a nationally representative sample of 25,417 adults interviewed in the National Health Interview Survey (NHIS) in 2018. A relatively large fraction of individuals prioritized for the earliest distribution of the vaccine are women, non-Hispanic Black, and young to middle aged adults. Overall, the study provides a platform to track equity in vaccine coverage and to better tailor health communication strategies.

Young Adult Human Papillomavirus and Influenza Vaccine Coverage: A Comparison Across College Enrollment Status

To determine human papillomavirus and influenza vaccine coverage among young adults in the US and assess differences in vaccine uptake by college enrollment status, we conducted an online survey of young adults aged 18-26 (n = 417) using Survey Monkey, with recruitment occurring through Amazon's Mechanical Turk (MTurk) platform. We collected data on self-reported preventive health behaviors, including vaccine receipt, current college enrollment status, and other demographics. Overall, 49% of participants reported receiving at least one dose of human papillomavirus vaccine and 57% reported receiving at least one influenza vaccine over the past three years. Vaccine coverage estimates did not differ between college-enrolled and non-enrolled respondents. Low vaccine coverage rates demonstrate the need to improve vaccine strategies for young adults. The strongest predictor of vaccine receipt was having received a provider recommendation. There does not appear to be healthcare utilization differences related to ability to access care through student health or community-based settings. Additional research is needed to develop interventions to improve vaccination coverage among young adults, both currently enrolled and not enrolled in college.

Racial/Ethnic Disparities in Maternal Vaccine Knowledge, Attitudes, and Intentions

OBJECTIVES

Although disparities in maternal vaccine acceptance among racial/ethnic groups are well documented, the reasons for these disparities are unclear. The objective of this study was to describe differences in pregnant women's knowledge, attitudes, beliefs, intentions, and trust regarding maternal and infant vaccines by race/ethnicity.

METHODS

We collected survey data from 1862 pregnant women from diverse prenatal care practices in Georgia and Colorado from June 2017 through July 2018. We performed multiple logistic regressions to determine differences in intentions, knowledge, attitudes, beliefs, and trust by race/ethnicity and calculated odds ratios (ORs) and 95% CIs.

RESULTS

Compared with White women, Black and Hispanic women were less confident in vaccine safety and efficacy and less likely to perceive risk of acquiring vaccine-preventable diseases, report provaccine social norms, indicate having enough vaccine knowledge, and trust vaccine information from health care providers and public health authorities. Black women were the least confident in the safety of the maternal influenza vaccine (OR = 0.37; 95% CI, 0.27-0.49); maternal tetanus, diphtheria, and acellular pertussis vaccine (OR = 0.37; 95% CI, 0.27-0.52); and infant vaccines overall (OR = 0.40; 95% CI, 0.28-0.58), and were least likely to intend to receive both maternal vaccines (OR = 0.35; 95% CI, 0.27-0.47) or all infant vaccines on time (OR = 0.45; 95% CI, 0.34-0.61) as compared with White women.

CONCLUSIONS

Understanding differences in behavioral constructs integral to vaccine decision making among women of different races/ethnicities can lead to tailored interventions to improve vaccine acceptance.

Practice-, provider- and patient-level facilitators of and barriers to HPV vaccine promotion and uptake in Georgia: a qualitative study of healthcare providers' perspectives

Georgia experiences higher human papillomavirus (HPV)-associated cancer burden and lower HPV vaccine uptake compared with national estimates. Using the P3 model that concomitantly assesses practice-, provider- and patient-level factors influencing health behaviors, we examined facilitators of and barriers to HPV vaccine promotion and uptake in Georgia. In 2018, we conducted six focus groups with 55 providers. Questions focused on multilevel facilitators of and barriers to HPV vaccine promotion and uptake. Our analysis was guided by the P3 model and a deductive coding approach. We found that practice-level influences included organizational priorities of vaccinations, appointment scheduling, immunization registries/records, vaccine availability and coordination with community resources. Provider-level influences included time constraints, role, vaccine knowledge, self-efficacy to discuss HPV vaccine and vaccine confidence. Patient-level influences included trust, experiences with vaccine-preventable diseases, perceived high costs, perceived side effects and concerns with sexual activity. Findings suggest that interventions include incentives to boost vaccine rates and incorporate appointment scheduling technology. An emphasis should be placed on the use of immunization registries, improving across-practice information exchange, and providing education for providers on HPV vaccine. Patient-provider communication and trust emerge as intervention targets. Providers should be trained in addressing patient concerns related to costs, side effects and sexual activity.

Abstract PO-241: A multilevel exploration of determinants of human papillomavirus vaccine initiation among U.S. Vietnamese

Background: U.S. Vietnamese experience higher cervical cancer incidence and have lower human papillomavirus vaccine (HPVV) uptake compared to other racial/ethnic groups. Limited research has examined multilevel determinants of HPVV uptake among this population. This study used the P3 (practice-, provider-, and patient- level) model to examine multilevel determinants of U.S. Vietnamese parents’ HPVV initiation for their children. Methods: In 2020, we conducted an online cross-sectional survey of Vietnamese parents living in the U.S. who had ≥ one child aged 9-18. Parents were recruited through U.S. Vietnamese community-based organizations, U.S. Vietnamese-focused Facebook groups and listserv, and snowball sampling. Descriptive statistics and Chi-square tests were conducted to understand facilitators of and barriers to HPVV initiation (i.e. 1+ vaccine dose). Results: The sample represented 331 Vietnamese parents in 35 U.S. states. The majority of parents were female (84.6%), had ≥ Bachelor’s degree (87.3%), and an annual household income of $50,000+ (65.6%); 98.8% were born outside of the U.S, and 60.7% had difficulties understanding English medical information. Less than half of parents initiated HPVV for their children (43.5%). HPVV initiation significantly differed by whether parents had seen materials about HPVV at their children’s clinic (62.3% vs 26.2%, p&lt;.001). The most common facilitator of adolescent HPVV initiation was a doctor’s recommendation (80.0%) however, 55.3% reported that they had not received a doctor’s recommendation for HPVV for their children, and 59.7% of non- initiators indicated that not receiving a doctor’s recommendation was a barrier. A higher percentage of parents of female children reported HPVV initiation compared to parents of male children (52.4% vs 33.3%, p&lt;.001). Almost all parents reported a high degree of trust in scientists who develop vaccines, CDC, and FDA (&gt;90%) and believed that vaccines recommended for adolescents are safe (97%). Discussion: While this sample of U.S. Vietnamese parents has overall high socioeconomic status, adolescent HPVV initiation (43.5%) was still much lower than general U.S. populations (68.1% in 2018 NIS-Teen data), necessitating additional efforts to improve HPVV uptake among U.S. Vietnamese. Some findings were well-identified barriers (e.g., a lack of doctor’s recommendation, child’s sex) while others were novel (e.g., lack of access to clinic-based materials about HPVV). Findings regarding high degree of trust in vaccines and regulatory bodies can be incorporated in future interventions.

Citation Format: Milkie Vu, Carla J. Berg, Cam Escoffery, Victoria N. Huynh, Robert A. Bednarczyk. A multilevel exploration of determinants of human papillomavirus vaccine initiation among U.S. Vietnamese [abstract]. In: Proceedings of the AACR Virtual Conference: Thirteenth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2020 Oct 2-4. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(12 Suppl):Abstract nr PO-241.