Vaccine Initiation Research Articles

History of the medical licensure system in Korea from the late 1800s to 1992

The introduction of modern Western medicine in the late 19th century, notably through vaccination initiatives, marked the beginning of governmental involvement in medical licensure, with the licensing of doctors who performed vaccinations. The establishment of the national medical school "Euihakkyo" in 1899 further formalized medical education and licensure, granting graduates the privilege to practice medicine without additional examinations. The enactment of the Regulations on Doctors in 1900 by the Joseon government aimed to define doctor qualifications, including modern and traditional practitioners, comprehensively. However, resistance from the traditional medical community hindered its full implementation. During the Japanese colonial occupation of the Korean Peninsula from 1910 to 1945, the medical licensure system was controlled by colonial authorities, leading to the marginalization of traditional Korean medicine and the imposition of imperial hierarchical structures. Following liberation in 1945 from Japanese colonial rule, the Korean government undertook significant reforms, culminating in the National Medical Law, which was enacted in 1951. This law redefined doctor qualifications and reinstated the status of traditional Korean medicine. The introduction of national examinations for physicians increased state involvement in ensuring medical competence. The privatization of the Korean Medical Licensing Examination led to the establishment of the Korea Health Personnel Licensing Examination Institute in 1992, which assumed responsibility for administering licensing examinations for all healthcare workers. This shift reflected a move towards specialized management of professional standards. The evolution of the medical licensure system in Korea illustrates a dynamic process shaped by the historical context, balancing the protection of public health with the rights of medical practitioners.

Post-vaccination Alteration in Meningococcal Disease Rate in the US from 1980-2019

Aim: To study the impact of vaccination on Meningococcal infection in the United States from 1980 to 2019. Study Design: The study used deidentified publicly available data. Place and Duration of Study: Department of Anatomical & Developmental Sciences, and Pathological Processes, Microbiology & Immunology, Department of Preventive Medicine & Epidemiology, Department of Nutritional, Biochemical & Molecular Sciences American University, School of Medicine, Aruba, Between July 2023 to September 2023. Methodology: All analyses for this study were conducted using The Health, United States Data Finder, Center for Disease Control, which provides detailed trend tables and charts for recent editions of Health, United States. All the data was collected and compared year-wise, age-wise, and new cases of meningococcal infection per 100,000 population. The data was also compared concerning the year of initiation of the vaccine. Results: With time, it was observed that the cases of meningococcal infection declined. The rate was found to be higher with the initiation of vaccination. Conclusion: Stringent vaccination, surveillance, and timely use of antibiotics in the United States contributed to the drop in instances of meningococcal infection. However, the recent outbreak in Florida could be due to negligence among the people.

Underutilization of Influenza Antiviral Treatment Among Children and Adolescents at Higher Risk for Influenza-Associated Complications - United States, 2023-2024.

Annually, tens of thousands of U.S. children and adolescents are hospitalized with seasonal influenza virus infection. Both influenza vaccination and early initiation of antiviral treatment can reduce complications of influenza. Using data from two U.S. influenza surveillance networks for children and adolescents aged <18 years with medically attended, laboratory-confirmed influenza for whom antiviral treatment is recommended, the percentage who received treatment was calculated. Trends in antiviral treatment of children and adolescents hospitalized with influenza from the 2017-18 to the 2023-2024 influenza seasons were also examined. Since 2017-18, when 70%-86% of hospitalized children and adolescents with influenza received antiviral treatment, the proportion receiving treatment notably declined. Among children and adolescents with influenza during the 2023-24 season, 52%-59% of those hospitalized received antiviral treatment. During the 2023-24 season, 31% of those at higher risk for influenza complications seen in the outpatient setting in one network were prescribed antiviral treatment. These findings demonstrate that influenza antiviral treatment is underutilized among children and adolescents who could benefit from treatment. All hospitalized children and adolescents, and those at higher risk for influenza complications in the outpatient setting, should receive antiviral treatment as soon as possible for suspected or confirmed influenza.

Quality Initiative to Increase Early Initiation and Series Completion of HPV Vaccine and its Impact on Health Disparities

ObjectiveHPV infection is associated with a large burden of disease prevalence, morbidity, and known disparities. HPV vaccination rates remain lower than other childhood immunizations, despite vaccine safety and effectiveness. The objective of this QI intervention was to improve HPV vaccination rate by 15% over 3-years through early initiation and analyze trends across health disparities. MethodsQI study in ages 9 to 13 at Nemours Primary Care from 2019 to 2022, which includes rural and urban regions and diverse populations. Interventions included updating EHR to begin at age 9, practice-level feedback, and updated education. Primary outcome measure was the HEDIS rate for HPV vaccination (proportion completed by age 13). Process measure was early HPV vaccine initiation rate (proportion aged 9-10 with at least one dose). Year-end early HPV vaccine initiation rates were analyzed to assess trends by race and ethnicity, geography, insurance, and Child Opportunity Index (COI). ResultsThe number of eligible 9 and 10 year olds ranged from 16,466 to 17,925 annually. HEDIS rates improved over three years from 49.2% to 59.5% (p < 0.0001). Early initiation increased from 13.2% in 2019 to 42.2% in 2022 (p < 0.0001) and improved significantly across demographic variables (p < 0.0001). Groups with the lowest baseline early vaccination rates increased significantly. ConclusionHPV vaccine completion by 13 increased significantly with QI supporting early initiation. Demographic analyses showed the highest degree of improvement in populations with the lowest baseline rates. This supports altering CDC recommendation for HPV vaccination initiation at ages 9-12.

India’s Vaccine Diplomacy and Global Health Governance: A Soft Power Approach in the Context of Public Policy and Religious Values

Research Problem: India's vaccine diplomacy during the Covid-19 pandemic has not only emerged as a significant tool of soft power but also involves moral and ethical dimensions closely tied to religious values and public policy. In the midst of a global crisis, the interaction between India’s vaccine diplomacy and the religious and public policy frameworks of recipient nations requires deeper exploration. Research purposes: This article aims to analyze the role of India’s vaccine diplomacy in relation to public policy and religious values in recipient countries, examining how India’s global health initiatives influence moral and ethical perceptions of vaccine distribution, fairness, and international solidarity. Research methods: The study employs policy analysis through a comprehensive literature review, focusing on the relationship between vaccine diplomacy, public policy, and responses from religious communities in the recipient countries. It also explores the ethical and spiritual dimensions of India’s health diplomacy approach and its impact on public health policies. Results and Discussion: The findings reveal that India’s vaccine diplomacy, through initiatives like "Vaccine Maitri," not only strengthens political ties with neighboring and global countries but also interacts with religious value systems, influencing public acceptance of vaccines. Moral values such as solidarity and justice, integral to many religious traditions, reinforce positive responses to the vaccine initiatives. Additionally, in some nations, religious communities have played a significant role in promoting vaccine acceptance by framing the health response in moral terms. Research Implications and Contributions: This research highlights the importance of integrating religious values into public health policy, particularly in global health contexts. Vaccine diplomacy rooted in moral solidarity and universal ethical principles, aligned with religious values, has the potential to enhance international cooperation and reduce vaccine hesitancy. Thus, this study contributes to understanding how religion and public policy can collaborate effectively in addressing global health challenges.

Lesson learned from a co-designed vaccination initiative with undocumented people in the Netherlands

Abstract Issue/ problem ‘The coronavirus does not take document status into account’. The COVID-19 pandemic highlighted the importance of equal healthcare access for all. Yet, undocumented people face numerous personal and practical barriers in accessing health. Ensuring the protection of the most vulnerable is a global concern. Description of the problem In 2021, a regional initiative aimed to remove barriers and create a trusted environment for undocumented people to receive vaccinations. This collaborative effort included public health departments, NGO’s, community groups, (self) organized migrant organizations, GP’s and embassies. Regular meetings identified the population’s needs. A medical doctor was made available 24/7 to address questions and concerns. Actions were undertaken to build trust, foster collaborations between health authorities and communities and to improve vaccine service access and design. Results Working in partnership fostered trusted, multi-sectorial relationships, resulting in a vaccination initiative that met the diverse needs of the undocumented people. Widespread community-driven outreach through flyers and social media reached those who normally are not reached. Supported by over 40 volunteers, three vaccination events were organized in which 693 doses were administered. All parties made their contribution, e.g. with different migrant communities providing hot meals. The initiative began at the grassroots level in the communities and was then executed in partnership with the involved parties, making it highly successful. Lessons Inclusive engagement, addressing concerns and sharing clear information not only supports trusted relationships but also strengthens social cohesion. Collaborating directly with the communities ensured the initiative was tailored to their needs, thereby lowering the barriers for accessing healthcare. Achieving this success required a foundation of trust, mutual respect and a collective commitment from all involved. Key messages • Codesigning vaccination initiatives with the communities is essential for success. • Trusted partnerships, community involvement and mutual commitment were key elements for lowering barriers to accessing health.

Preferences regarding the Booster Dose of Covid-19: a cross-sectional study in Central Italy

Abstract Background Examining information sources, communication channels, and preferred content formats is crucial for adapting and improving future communication strategies in vaccination campaigns. This study aims to evaluate the information and communication preferences regarding the booster dose of Covid-19 among employees of the Central Tuscany Local Health Authority (CT-LHA). Methods From July to October 2022, a questionnaire was administered to 7,000 out of approximately 15,000 CT-LHA employees. The questionnaire analyzed communication, organizational, and access aspects regarding preferences for the Covid-19 booster dose. The sample was stratified into healthcare workers (HCWs) and non-healthcare workers (NHCWs). Chi-squared tests were performed using STATA, with the significance level set at 95%. Results The returned questionnaires were 1,885 (26.9%), with the majority being HCWs (64.4%). HCWs rated the quality of communication significantly lower compared to NHCWs, who rated it very high (p &amp;lt; 0.05). HCWs also rated the ease of booking the Covid-19 booster dose and access modalities to vaccination significantly lower than NHCWs (p &amp;lt; 0.05). NHCWs expressed a preference for receiving scientific information from Ministry of Health tutorials, while HCWs preferred information from their general practitioner (p &amp;lt; 0.05). HCWs preferred to receive organizational information from healthcare management, while NHCWs preferred information from vaccination physicians (p &amp;lt; 0.05). Additionally, HCWs preferred company operating procedures for disseminating information, whereas NHCWs preferred corporate communications circulars (p &amp;lt; 0.05). Conclusions HCWs and NHCWs showed differences in perceived quality of communication, ease of access to vaccination services, and preferred sources of information. HCWs rated the quality of communication and access to vaccination services lower than NHCWs. This results suggest the need for tailored communication strategies to effectively reach both groups. Key messages • Health organizations need to develop targeted communication approaches that address the specific needs and preferences of their employees. • Flexibility and adaptability are crucial to adapt communication methods and channels to strengthen vaccination initiatives and promote public health outcomes.

Vaccine-preventable diseases in migrants to Europe: a systematic review

Abstract Migrant populations in Europe are at increased risk of under-immunisation and therefore likely to be at high risk of vaccine-preventable diseases (VPD), yet the relationship between migration and VPD incidence is not fully understood. This study aimed to explore the prevalence of VPDs in migrant populations in Europe and to define at-risk groups. Following PRISMA guidelines, Embase, MEDLINE and Global Health were searched for peer-reviewed papers published from 1st January 2010. Inclusion criteria comprised primary research on VPD cases (measles, mumps, rubella, diphtheria, pertussis, tetanus) among migrants to/within EU/EEA and Switzerland. We defined migrants as foreign-born nationals. Forty-seven eligible studies from 15 EU/EEA countries and Switzerland were included, with a total of 1357 migrant VPD cases reported. Analysis revealed 1357 migrant cases across measles (28 publications; 926 cases), pertussis (9; 267 cases), mumps (9; 107 cases), diphtheria (11; 67 cases), rubella (2; 6 cases imported from Romania and Pakistan), tetanus (2; 2 cases). Over-representation of measles cases was observed among migrant children and adolescents, predominantly from the WHO Europe region (particularly Bulgaria, Bosnia and Herzegovina and Serbia). Migrants of East African origin were over-represented among diphtheria cases. This study underscores the association between migration and VPD cases in EU/EEA and Switzerland, establishing a clear association between European migrant children and adolescents in measles outbreaks, and adult migrants from East Africa in diphtheria cases. This study suggests strengthening systems for targeted catch-up vaccination for migrants is imperative upon arrival in European countries to align them with national schedules, alongside the need to improve data collection and surveillance systems to inform effective public health interventions. Key messages • Migrant populations in Europe face heightened risk of vaccine-preventable diseases and need to be better incorporated into catch-up vaccination initiatives on arrival. • Improved data collection and surveillance systems are crucial for informing effective public health interventions targeting migrant populations.

3.I. Scientific session: Increasing EU preparedness and improving European Vaccination Beyond COVID-19: the EUVABECO approach

Abstract This workshop provides a platform for delegates to enhance their understanding of the interdisciplinary approach developed in the European Vaccination Beyond COVID-19 (EUVABECO) project, funded under the European Commission’s EU4Health programme. The project is to build and validate implementation plans for EU Member States (MS) to equip them with operational and technical tools to enhance vaccination practices both in routine vaccination and in case of future outbreaks. Validation will be based on innovative practices that emerged in the context of the COVID-19 pandemic. Ultimately, EUVABECO will provide MS with robust implementation plans for common tools to support said innovative vaccination practices, thus, enhancing preparedness and increasing resilience against future health threats in Europe and globally. Guided by two chairs, the workshop is structured around five brief interactive presentations to deliver the conceptualisation, methodologies, and early results and vision for vaccination beyond COVID-19. It is designed to highlight how project activities strengthen resilience and increase preparedness against communicable diseases across the EU and beyond its borders, whilst brokering dialogue on related public health priorities. The presentations will focus on: 1. Preparing for future public health crises by fostering a conducive environment. 2. Enhancing preparedness by developing robust implementation plans. 3. An interdisciplinary approach: Exploring the five dimensions (medical/clinical, social, industrial, modelling and forecasting, and digital) of the tools deployed by EUVABECO. 4. The vital role of stakeholders and of the National Immunization Technical Advisory Groups (NITAGs). 5. Future actions and a call for ongoing support and collaboration in a structured manner. The session will also give the opportunity to formally present EUVABECO’s multistakeholder approach and to formally launch the EU Vaccination Stakeholder Forum, where early access will be granted to EU MS for the various resources generate. This will allow the audience to give input about the needs of the broader public health community involved in vaccination across the EU, for the Stakeholder Forum to effectively promote and support: • The scaling up of existing implementation plans within MS; • The development of new implementation plans for additional tools; • Integration between public health and primary care; • Inform the targeted interaction with EU and MS bodies involved in related policies and decision-making. The presentations will be augmented by real-time polling to maximize participant engagement. This approach will maximize interaction whilst eliciting critical insights into stakeholders’ knowledge, attitudes, and practices concerning EUVABECO’s tools and strategies. This type of engagement will ensure effective knowledge transfer and a comprehensive understanding of the project’s objectives and implementation strategies. Key messages • Enhancing vaccination preparedness requires an evidence-based and harmonized set of tools to be deployed across EU MS. EUVABECO will deliver validated implementation plans to achieve this. • An interdisciplinary approach and multistakeholder engagement are critical for evidence-informed decision-making and harmonization to successfully deploy vaccination initiatives across the EU.

43 Etiology of community-acquired bacterial meningitis in children seen in the emergency department in Canada

Abstract Background Bacterial meningitis poses a significant threat to paediatric health, resulting in substantial morbidity and mortality in children. Though previous studies have delineated the causative agents behind community-acquired meningitis, recent vaccination initiatives may have reshaped its underlying etiology. Objectives This study aimed to identify the bacteria responsible for community-acquired bacterial meningitis in children in Canada. Design/Methods This was a retrospective cohort study including children aged 1 day-18 years with confirmed bacterial meningitis, evaluated at a tertiary-care, Canadian emergency department between July 1st 2014 and December 31st 2022. The primary outcome was the pathogen identified. Other variables of interest were mortality, complications, age, sex, and diagnostic method. Medical charts were identified via the hospital’s archives and reviewed by a single co-author. A random sample of 20 (23%) medical charts were independently reviewed by a second co-author to assess inter-rater reliability. We set a target of evaluating at least 50 cases to allow narrow confidence intervals (+/- 13%) for proportions. Results All variables showed excellent inter-rater reliability with Kappa scores and intraclass correlation coefficients higher than 0.60. All 79 eligible cases were included. The main causal agents were Group B Streptococcus (GBS) (n=20; 25%), Streptococcus pneumoniae (n=16; 20%), Neisseria meningitidis (n=16; 20%) and Haemophilus influenzae (n=9; 11%). Etiology exhibited age-dependent variations, with 85% of GBS and 100% of E. coli infections identified in children under two months, while all pneumococcal and Group A Streptococcus cases were in children older than six months. All children infected by S. pneumoniae were vaccinated against pneumococcal infection but the serotype was not covered by vaccination in 7/8 infections. All children with N. meningitidis were either too young to be vaccinated (n=10) or infected by a serotype not covered by the vaccine. Six (7%) patients died and 29 (34%) suffered complications, including hearing impairment (n=5), cerebral ischemia (n=4), seizures (n=4), and subdural abscess (n=3). Fifty-nine bacterias were identified by cerebrospinal fluid culture, 13 by PCR and 7 by both methods. Conclusion GBS is the leading etiology of paediatric community-acquired bacterial meningitis in Canada. Causal agents of bacterial meningitis vary greatly by age. Future studies should work on improving the serotype spectrum of vaccines, prophylaxis in mothers who are GBS carriers, and use of PCR as a diagnostic tool for timely clinical interventions.

COVID-19 vaccine implementation at a syringe services program: experiences of frontline staff

BackgroundWhile people with substance use disorders, including people who inject drugs (PWID), experience increased risk for COVID-19 infection and adverse outcomes, COVID-19 vaccination rates among PWID are consistently lower than those observed in the general population. Offering COVID-19 vaccines at syringe services programs (SSPs) has been proposed as a critical strategy to increase vaccine uptake among this population. We explored the experiences of frontline staff at an SSP in Miami, Florida implementing onsite COVID-19 vaccines.MethodsBetween June and July 2022, we conducted in-depth semi-structured interviews with 17 staff members of an SSP in Miami, Florida. Data collection and codebook thematic analysis of transcribed interviews were guided by the Consolidated Framework for Implementation Research (CFIR).ResultsFacilitators and barriers of COVID-19 vaccine implementation at the SSP aligned with all major CFIR domains. Key facilitators included the SSP’s established partnership with the local health department for vaccine distribution, its existing funding sources which could be leveraged for vaccine-related expenses, consensus among staff about the need for new strategies to increase vaccine uptake among PWID, and PWID’s trust in the SSP. Major—but largely modifiable—barriers included lack of participant compensation, limited internal collaboration and communication regarding the vaccine initiative beyond implementation leads and innovation deliverers due to competing priorities and segmented roles and responsibilities, and insufficient involvement of the most participant-facing staff (i.e., the SSP’s peer navigators and outreach workers).ConclusionsImplementing onsite COVID-19 vaccines was perceived as feasible and acceptable by frontline staff at the SSP, however contextual factors impeded optimal implementation. Multilevel strategies, such as participant compensation for vaccine completion and internal educational meetings with staff to improve vaccine implementation and reach, are required. As a trusted source of preventative services for PWID, SSPs are an underutilized venue for increasing vaccine uptake among this population, and findings from this study could inform the expansion of low-barrier vaccine services at SSPs nationwide.

Meeting People Where They Are in the Fight Against COVID-19 and Its Complications.

The COVID-19 pandemic exacerbated socioeconomic and racial disparities. Because of the institution's commitment to health equity, Morehouse School of Medicine, one of four Historically Black College and University (HBCU) medical schools, took the leadership role in addressing disparities by becoming a community vaccination provider. With vaccines registered, ordered, and received from the Georgia Department of Public Health through the mobile community vaccine initiative, the Medical School vaccinated more than 2700 people in the metropolitan Atlanta area. The initiative took place from January 2021, shortly after the COVID-19 vaccines were initially released, until April 2022 when vaccinations became part of routine health maintenance and preventive health measures at the school. Eighty-six percent of the individuals vaccinated were African American or Hispanic/Latino. Our efforts highlighted the importance of addressing vaccine access barriers and providing culturally sensitive care. (Am J Public Health. Published online ahead of print October 15, 2024:e1-e4. https://doi.org/10.2105/AJPH.2024.307768).

HPV Vaccination Stages and Associated Factors Among Children of Immigrant Women.

This study aimed to identify key determinants by stage of implementation of human papillomavirus (HPV) vaccination among children of immigrant women in South Korea. Cross-sectional descriptive study. The sample comprised 262 Chinese, Vietnamese, and Korean-Chinese women with children living in South Korea. The survey was conducted using self-report questionnaires. The HPV vaccination levels in children were classified into four transition stages. Sequential logistic regression analysis was conducted to identify the factors affecting the transition of HPV vaccination status. Social norms had the greatest influence on the intention to vaccinate. Perceived barriers were a significant factor associated with intention or initiation of vaccination, whereas perceived severity and susceptibility were associated with the intention and initiation stages, respectively. Upon the initiation of HPV vaccination, low perception of discrimination in healthcare was associated with continued vaccination. Given the importance of completing multiple doses of the HPV vaccine within a given timeframe, it is important to provide culturally appropriate interventions in stages to prevent dropouts.

Accountable care organizations and HPV vaccine uptake: a multilevel analysis.

To examine associations between accountable care organization (ACO) membership and human papillomavirus (HPV) vaccination and to evaluate variation in HPV vaccination across ACO providers. Retrospective cohort study. We analyzed the records of commercially insured children and adolescents aged 11 to 14 years using Connecticut's All-Payer Claims Database from January 2012 to December 2017. A total of 23,911 adolescents receiving care from 933 ACO-attributable providers and 923 non-ACO-attributable providers were included. The mean rate of HPV vaccine initiation was 53% overall (51% among boys, 55% among girls). Among those who initiated the vaccine, the mean rate of HPV vaccine completion was 69% (67% among boys, 70% among girls). Adolescents receiving care at ACOs vs non-ACOs were significantly more likely to receive initial HPV vaccination (OR, 1.80; 95% CI, 1.69-1.91) and to complete the HPV vaccine series (OR, 1.12; 95% CI, 1.01-1.23). Among adolescents receiving care in ACOs, providers were responsible for 14% of variability in HPV vaccine initiation and 10% of variability in HPV vaccine completion and ACOs were responsible for less than 1% of variability in HPV vaccine initiation and completion. Adolescents receiving care from ACOs were significantly more likely to initiate and complete HPV vaccination than were adolescents receiving care in non-ACO settings. Variation in HPV vaccine uptake attributable to providers within ACOs dwarfed variation attributable to ACOs, indicating that vaccine uptake was more dependent on the provider irrespective of the ACO with which they were affiliated. Efforts to improve HPV vaccination rates may require provider-focused interventions regardless of the overall performance of their health care system orproviderorganization.

The effect of Plasmodium falciparum exposure and maternal anti-circumsporozoite protein antibodies on responses to RTS,S/AS01E vaccination in infants and children: an ancillary observational immunological study to a phase 3, randomised clinical trial

The RTS,S/AS01E malaria vaccine showed lower antibody response and protective efficacy in infants aged 6-12 weeks compared with children aged 5-17 months (for whom this vaccine is recommended). We aimed to study the effect of previous Plasmodium falciparum exposure on the antibody responses to RTS,S/AS01E vaccination in infants and children, and the mediating effect of baseline (including maternal) anti-circumsporozoite protein (CSP) antibodies. In this observational study, we included children and infants from six African countries (Burkina Faso, Gabon, Ghana, Kenya, Mozambique, and Tanzania) enrolled in the MAL067 immunology ancillary study of the RTS,S/AS01E phase 3 clinical trial from March 27, 2009, to Jan 21, 2011. We used comparator-vaccinated infants and children to identify antibody-based signatures of previous P falciparum exposure, which were later applied to RTS,S/AS01E-vaccinated infants and children. In these participants, we explored the relationship between vaccine antibody immunoglobulin G (IgG) responses measured by ELISA and pre-vaccination serological markers of malaria exposure by assessing the IgG levels against 1000 P falciparum antigens using partial proteome microarrays. We included 718 comparator-vaccinated infants (348 [48%]) and children (370 [52%]) and 606 RTS,S/AS01E-vaccinated infants (329 [54%]) and children (277 [46%]). Anti-CSP IgG responses to primary vaccination did not correlate with a baseline signature of previous exposure in children, suggesting that prior P falciparum exposure does not significantly affect antibody immunogenicity in children (Pearson's r=-0·02 [95% CI -0·13 to 0·10]). By contrast, high P falciparum exposure signature levels at the time of vaccination in infants, presumably driven by maternally transferred antibodies and declining within the initial 6-12 months of life, correlated with reduced RTS,S/AS01E responses (r=-0·17 [-0·27 to -0·06]). This negative correlation was stronger for anti-CSP IgG than for the exposure signature or any other more immunogenic blood stage P falciparum antigens (r=-0·42 [-0·50 to -0·33]), persisted after adjustment by baseline levels of the exposure signature (semi-partial correlation r=-0·44 [-0·55 to -0·33]), and involved antibodies to the central NANP region (r=-0·39 [-0·49 to -0·28]) but not the C-terminal region (r=0·02 [-0·10 to 0·15]) of CSP. The negative effect of maternal anti-CSP IgG in infants did not appear to be confounded by other malaria transmission-dependent variables. Interference between passive immunity and vaccine response is clinically significant and might affect the implementation of next-generation CSP-based vaccines for young infants and mothers as well as passive immunisation with human monoclonal antibodies. US National Institutes of Health, National Institute of Allergy and Infectious Diseases; PATH-Malaria Vaccine Initiative; Spanish Ministerio de Economía y Competitividad (Instituto de Salud Carlos III), European Regional Development Fund and European Social Fund; Fundación Ramón Areces; Spanish Ministry of Science and Innovation; and Generalitat de Catalunya (CERCA Program).

Abstract A162: The influence of parental barriers to healthcare on adolescent HPV vaccination uptake and completion among Latinos in Los Angeles

Abstract Objective: This study aims to investigate the association between parental barriers to healthcare access and HPV vaccination uptake among Latino adolescents in Los Angeles. Background: Human papillomavirus (HPV) induced cervical cancer (CC) remains a significant public health concern. Routine HPV vaccination has been recommended in the United States for girls since 2006 and boys since 2011 yet disparities in vaccine initiation and completion persist, particularly among Latino adolescents in Los Angeles. Methods: This cross-sectional study analyzed child data provided by mothers recruited from the Es Tiempo campaign (2016-2018). A total of 353 Latino adolescents aged 9 to 26 years were included in the sample. We used crosstabs to assess vaccine initiation and completion differences by child sex and birth order, while logistic regression models were used to evaluate the association between parental barriers to healthcare, such as lack of health insurance and access to a primary care provider (PCP), and HPV vaccination initiation. Results: Among the sample, 44% initiated the HPV vaccine, and 23% completed the series, with significantly higher rates among girls and firstborn children. Regarding barriers, lack of health insurance was associated with decreased odds of HPV vaccination uptake while access to a PCP showed a slight increase in vaccination uptake odds. Conclusion: HPV vaccination uptake among Latino adolescents in Los Angeles remains suboptimal, with disparities observed by gender and birth order. To improve public health outcomes, targeted interventions are needed to increase HPV vaccination uptake among Latino adolescent boys, and further research is needed to understand vaccine adherence patterns within families and among siblings. Moreover, while parental barriers to healthcare may influence vaccination uptake, future studies should also explore how factors like parental education level and socioeconomic status influence HPV vaccination status in combination with access barriers. Citation Format: Anju F. Kane, Lourdes Baezconde-Garbanati. The influence of parental barriers to healthcare on adolescent HPV vaccination uptake and completion among Latinos in Los Angeles [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr A162.

Abstract A066: Unmasking differences in adolescent HPV vaccine uptake in six Asian American subgroups: data from the national immunization survey-teen (2015-2019)

Abstract Introduction: The HPV vaccination rates among Asian American adolescents were found to be below optimal levels. Understanding the high-risk demographics and the various factors influencing HPV vaccine acceptance is essential for addressing disparities and enhancing vaccination rates in this population. This study aimed to investigate HPV vaccine uptake in adolescents aged 13 to 17 across six major Asian American ethnic groups using nationally representative data. Methods: The study analyzed data from the National Immunization Survey- Teen (2015-2019), comprising 3,968 Asian American adolescents from Asian Indian, Chinese, Filipino, Japanese, Korean, and Vietnamese backgrounds. Provider and practice characteristics were examined alongside HPV vaccine initiation and completion rates within each subgroup. Results: Findings revealed that while the overall initiation rate among Asian American adolescents was 66.65%, significant variations existed among subgroups, ranging from 57.3% in Asian Indians to 71.22% in Chinese adolescents. Similarly, completion rates ranged from 30.89% in Asian Indians to 48.14% in Chinese adolescents, with an aggregated completion rate of 40.37% for the total Asian American sample. Household survey data generally showed lower initiation and completion rates compared to provider-reported data but still reflected subgroup disparities. Conclusion: Across all ethnic groups, a common barrier to HPV vaccination was the lack of physician recommendation. However, slight variations in this barrier were observed among subgroups. These findings underscore the importance of considering socioeconomic, cultural, and acculturation-related factors in designing effective public health and clinical interventions to promote HPV vaccination among Asian American adolescents. Citation Format: Lin Zhu, Elaine Z. Liu, Philip Siu, Chun Pan, Grace X. Ma. Unmasking differences in adolescent HPV vaccine uptake in six Asian American subgroups: data from the national immunization survey-teen (2015-2019) [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr A066.

Abstract B069: Designing a Hispanic/Latino community-driven HPV vaccine and HPV-related cancer awareness campaign for young adults and youth in Los Angeles County

Abstract Background: In Los Angeles, HPV vaccination is lowest among Hispanic/Latino (HL) youth, young adults, and HL adolescent girls of immigrant parents, despite HPV vaccination preventing more than 90% of cancers attributed to HPV infection. This study aims to address gaps in the HPV vaccine and HPV-related cancer awareness through community-driven exploration of multimedia sources and cultural tailoring of the Es Tiempo Campaign to HPV vaccine initiation materials. Methods: A mixed-methods design was used, combining quantitative surveys, qualitative listening sessions and focus groups. In May 2024, five youth between 14 and 17 years of age and seven young adults between 18 and 30 years of age who self-identified as HL were recruited through community outreach in Los Angeles. The twelve participants were surveyed and participated in two 90-minute Listening Sessions (grouped by age) to gather formative data. During the LS, participants reviewed culturally tailored designs of media materials (e.g., banners, posters) focused on HPV vaccination initiation. Focus groups with another twelve young adults gathered confirmative data. Descriptive statistics assessed demographics. Coding of transcripts identified themes. Results: Preliminary results from the Listening Sessions found that youth and young adults had similarities and differences in their preferences for receiving health information. Both age groups preferred health materials with visually appealing images and materials that could be easily found and distributed. All relied on health information provided by their providers including informational pamphlets, texts, and emails. Differences were found in whom they sought health advice from. Youths sought health advice from parents or family, while young adults did this too but only after reviewing health information first online. Both age groups identified social media, such as Instagram and TikTok as key sources for health information. However, neither group wanted to receive health information through Facebook or Twitter. Young adults wanted images showing HL patient-provider interactions, while youth preferred images of family or community. Youth liked cartoon-style images, but young adults wanted images of real HL people. For cultural tailoring, youth liked images that reflected a traditional colorful border. Young adults found this border was not representative of diverse HL communities. Conclusion: Community-driven research identified gaps in tailoring and guiding multimedia dissemination efforts for HPV vaccine initiation campaign materials among youth and young adults in the HL community. HL youth and young adults, as community informants, provided advice on multimedia platforms, design appropriateness, and comprehension. Community participation is essential to identify and create culturally competent designs at an appropriate literacy/language and age level and to produce materials for educational campaigns that are not only culturally specific but also visually appealing to the target population. Citation Format: Samantha Verganza, Patricia Escobedo, Rosa Barahona, Lourdes Baezconde-Garbanati. Designing a Hispanic/Latino community-driven HPV vaccine and HPV-related cancer awareness campaign for young adults and youth in Los Angeles County [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr B069.

Abstract A065: How accurate are parents' recalls? Factors affecting the concordance of parental and provider reports of HPV vaccination among African American adolescents

Abstract Objectives. Since the introduction of the human papillomavirus (HPV) vaccine in 2006, substantial efforts have been made at the national and state levels to monitor its uptake and understand the factors influencing vaccination. Most studies have focused on the acceptability and intent to vaccinate among adolescents and their parents, providing limited insights into how this understanding affects actual vaccine uptake and completion. A common method for measuring adolescents' vaccination status is parental recall. While some research has assessed the accuracy of parental recall, its implications have not been thoroughly explored. African Americans are disproportionately affected by HPV-related cancers, with higher mortality rates for cervical and oropharyngeal cancers compared to non-Hispanic whites. This study examined the accuracy of parents' reports of their adolescent children's HPV vaccination status and how this accuracy varied by socio-demographic characteristics within the Black/African American community. Methods. Data were taken from the 2015–2019 National Immunization Survey (NIS)-Teen, which includes a household interview and a provider-completed immunization history. We evaluated concordance between parents’ and providers’ reports of teens’ HPV vaccine initiation (at least 1 dose) and completion (3 doses) among Black/African American adolescents between the age of 13 to 17. We assessed bivariate associations of sociodemographic characteristics with having a concordant, false-positive (overreporting) or false-negative (underreporting) report, and used multinomial logistic regression to estimate the independent impact of each characteristic. Results: In a cohort of 68,205 adolescents (51.2% male, 95% CI: 50.4%-51.8%; 48.8% female, 95% CI: 48.2%-49.5%), parental reporting discrepancies in vaccination status were observed. Girls' parents were more likely to underreport (β=0.10, p=0.03) and overreport (β=0.10, p=0.03) vaccination status compared to boys' parents. Mothers with higher education levels were less likely to underreport, while single mothers were more likely to underreport (β=0.15, p=0.02) and overreport (β=0.17, p=0.008) vaccination status. Conclusions: Discrepancies between physician-reported and parental-reported HPV vaccination records among African American teenagers were observed, with parental reporting accuracy varying based on the child's gender and the mother's education level and marital status. Strategies to improve parental reporting accuracy and address disparities are needed to increase HPV vaccination rates and reduce HPV-related diseases in the African American community. Citation Format: Elaine Z. Liu, Philip Siu, Chun Pan, Grace X. Ma, Lin Zhu. How accurate are parents' recalls? Factors affecting the concordance of parental and provider reports of HPV vaccination among African American adolescents [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr A065.

Abstract A143: The development of a risk prediction model to predict patients’ likelihood of completing human papillomavirus vaccination

Abstract Background: Human Papillomavirus (HPV) cancers can be preventable if HPV vaccination is received in adolescents before the age of 13, yet only 55% of Oregonian adolescents had an HPV series completion in 2020.2 The recommended vaccination age for HPV recently dropped to age 9. This new recommended age allows providers to offer HPV vaccination with routine vaccinations. To further increase HPV vaccination rates, research is critically needed on new interventions to promote vaccination among vaccine resistant groups, and populations that are most in need of targeted interventions. We assessed patterns in vaccination from 2015-2022, in preparation of the development of a prognostic risk prediction model to identify patients’ likelihood of obtaining HPV vaccination. Methods: We used a retrospective cohort from a large health system to assess vaccination patterns from 2015-2022. Eligible patients were members of Kaiser Permanente Northwest, 9-18 years old, and did not have a history of adverse vaccination outcomes. We assessed vaccination initiation, completion by age, gender and year. Results: Among 29,398 eligible patients, 44.3% had no vaccination, 14.5% had one dose, and 41.2% had completed the series. More patients were vaccinating at earlier ages from 2015-2022. Of those with one dose or who had completed the series, 84% had vaccinated by the age of 12 in 2022 compared to 74% in 2015. The change was greater in boys with 70.5% before age 12 in 2015 compared with 84% in 2022. ConclusionsWhile efforts to increase HPV vaccination and initiate at younger ages have been successful, efforts need to be targeted to specific populations. The patterns of HPV vaccination over the past 7 years highlights improvement, but system level interventions may be needed to adequately increase vaccination among resistant populations. This presentation will discuss the assessment of vaccination patterns in preparation of the development of a prognostic risk prediction model and describe how the model will be used in a system to target populations for early interventions to complete vaccination. Citation Format: Amanda A. Petrik, Matthew Slaugher, Gloria Coronado, Eric Johnson. The development of a risk prediction model to predict patients’ likelihood of completing human papillomavirus vaccination [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr A143.