The role of immunization in public health is crucial, offering widespread protection against infectious diseases and underpinning societal well-being. However, achieving optimal vaccination coverage is impeded by vaccine hesitancy, a significant challenge that necessitates comprehensive strategies to understand and mitigate its effects. We propose the integration of Population Health Management principles with Immunization Information Systems (IISs) to address vaccine hesitancy more effectively. Our approach leverages systematic health determinants analysis to identify at-risk populations and tailor interventions, thereby promoting vaccination coverage and public health responses. We call for the development of an enhanced version of the Italian National Vaccination Registry, which aims to facilitate real-time tracking of individuals\' vaccination status while improving data accuracy and interoperability among healthcare systems. This registry is designed to overcome current barriers by ensuring robust data protection, addressing cultural and organizational challenges, and integrating behavioral insights to foster informed public health campaigns. Our proposal aligns with the Italian National Vaccination Prevention Plan 2023-2025 and emphasizes proactive, evidence-based strategies to increase vaccination uptake and contrast the spread of vaccine-preventable diseases. The ultimate goal is to establish a data-driven, ethically sound framework that enhances public health outcomes and addresses the complexities of vaccine hesitancy within the Italian context and beyond.

OBJECTIVE: Adolescent human papillomavirus (HPV) vaccination rates continue to remain lower than other adolescent vaccines, both nationwide and in Iowa. This study examined predictors of missed opportunities for first-dose HPV vaccine administrations in Iowa in order to conduct more targeted outreach and improve adolescent HPV vaccine uptake.
METHODS: A retrospective study was conducted to identify predictors of missed opportunities for first-dose HPV vaccination in Iowa adolescents using Iowa\'s Immunization Registry Information System. The study population included 154,905 adolescents aged 11-15 years between 2019 and 2022. Missed opportunity for first-dose HPV vaccination was defined as a vaccination encounter where an adolescent received a Tdap and/or MenACWY vaccine but did not receive the first-dose HPV vaccine during the same encounter.
RESULTS: Over a third of the study population experienced a missed opportunity for HPV vaccination between 2019 and 2022. Missed opportunity for vaccination was most common among individuals living in a rural county (aOR = 1.36), underinsured adolescents (aOR = 1.74), males (aOR = 1.12), teens 13-15 years of age (aOR = 1.76), and White race and non-Hispanic ethnicity.
CONCLUSIONS: This study builds on previously reported predictors of missed opportunity for HPV vaccination in adolescents. Increased understanding of provider needs and barriers to administering HPV vaccination and further analysis of how the Vaccines for Children Program can play a role in HPV vaccination uptake is necessary to improve HPV vaccination rates among adolescents in Iowa and more specifically in rural communities.

The objective of this analysis was to evaluate and compare the effects of the COVID-19 pandemic on routine and annual influenza vaccination in Iowa, Minnesota, and North Dakota. Routine and annual influenza vaccination uptake and coverage between 2017 and 2021 was collected from each state\'s immunization information system (IIS) by age group and stratified by provider and vaccine type. Data from 2017 to 2019 were averaged to obtain a pre-pandemic baseline and compared to 2020 and 2021 data. Percent changes were calculated to evaluate differences in uptake and coverage. Changes in coverage and administration varied by state, but each state had some level of decreased administration across the different age groups and vaccine types. The most consistent decreases in vaccine administration occurred in the 15-year-old cohort with each state finding decreased administrations in 2020 and 2021. The 12-year-old age group had decreased administration of hepatitis B, measles, mumps, and rubella, and varicella vaccine while the 2-year-old age group had the most consistent decrease in coverage across all vaccines analyzed. Trends by provider type were also noted in all three states, with local public health (LPH) experiencing the largest and most consistent declines in vaccine administrations by age group. Adult influenza coverage improved to varying degrees in 2020 (+ 14.1% IA, + 2.1% MN, + 1.5% ND), but either decreased or approached the 2017-19 average in 2021. All three states saw some level of decreased vaccine administration across the age groups, vaccines, and provider types assessed. The COVID-19 pandemic affected how many children and adults received recommended immunizations, leaving communities vulnerable to vaccine-preventable diseases.

BACKGROUND: The electronic National Immunization Information System (NIIS) was introduced nationwide in Vietnam in 2017. Health workers were expected to use the NIIS alongside the legacy paper-based system. Starting in 2018, Hanoi and Son La provinces transitioned to paperless reporting. Interventions to support this transition included data guidelines and training, internet-based data review meetings, and additional supportive supervision visits.
OBJECTIVE: This study aims to assess (1) changes in NIIS data quality and use, (2) changes in immunization program outcomes, and (3) the economic costs of using the NIIS versus the traditional paper system.
METHODS: This mixed methods study took place in Hanoi and Son La provinces. It aimed to analyses pre- and postintervention data from various sources including the NIIS; household and health facility surveys; and interviews to measure NIIS data quality, data use, and immunization program outcomes. Financial data were collected at the national, provincial, district, and health facility levels through record review and interviews. An activity-based costing approach was conducted from a health system perspective.
RESULTS: NIIS data timeliness significantly improved from pre- to postintervention in both provinces. For example, the mean number of days from birth date to NIIS registration before and after intervention dropped from 18.6 (SD 65.5) to 5.7 (SD 31.4) days in Hanoi (P<.001) and from 36.1 (SD 94.2) to 11.7 (40.1) days in Son La (P<.001). Data from Son La showed that the completeness and accuracy improved, while Hanoi exhibited mixed results, possibly influenced by the COVID-19 pandemic. Data use improved; at postintervention, 100% (667/667) of facilities in both provinces used NIIS data for activities beyond monthly reporting compared with 34.8% (202/580) in Hanoi and 29.4% (55/187) in Son La at preintervention. Across nearly all antigens, the percentage of children who received the vaccine on time was higher in the postintervention cohort compared with the preintervention cohort. Up-front costs associated with developing and deploying the NIIS were estimated at US $0.48 per child in the study provinces. The commune health center level showed cost savings from changing from the paper system to the NIIS, mainly driven by human resource time savings. At the administrative level, incremental costs resulted from changing from the paper system to the NIIS, as some costs increased, such as labor costs for supportive supervision and additional capital costs for equipment associated with the NIIS.
CONCLUSIONS: The Hanoi and Son La provinces successfully transitioned to paperless reporting while maintaining or improving NIIS data quality and data use. However, improvements in data quality were not associated with improvements in the immunization program outcomes in both provinces. The COVID-19 pandemic likely had a negative influence on immunization program outcomes, particularly in Hanoi. These improvements entail up-front financial costs.

BACKGROUND: As the volume of immunization records increases, problems with fragmented records arise, especially since the majority of records in developing countries, including Indonesia, remain paper based. Implementing an immunization information system (IIS) offers a solution to this problem.
OBJECTIVE: In this study, we designed an integrated IIS prototype in Indonesia using the design science research (DSR) methodology.
METHODS: The stages of the DSR methodology followed in this study included identifying problems and motivating and defining objectives for a solution, design and development, demonstration, evaluation, communication, and drawing conclusions and suggestions. Specifically, this study began with problem formulation and a literature review. We then applied quantitative (questionnaire with 305 members of the public) and qualitative (interviews with 15 health workers including nurses, midwives, and doctors) data collection approaches.
RESULTS: The resulting high-fidelity prototype follows the 8 golden rules. There are 2 IIS designs, one for the public as immunization recipients and another for health workers. The functionalities include immunization history, schedule, recommendations, verification, certificates, reminders and recalls, coverage, monitoring, news, and reports of adverse events. Evaluation of the prototype was carried out through interviews and a questionnaire designed according to the System Usability Scale (SUS) and Post-Study System Usability Questionnaire (PSSUQ). The SUS value was 72.5 or \"Good (Acceptable),\" while the system usefulness, information quality, interface quality, and overall value on the PSSUQ were 2.65, 2.94, 2.48, and 2.71, respectively, which indicate it has an effective design.
CONCLUSIONS: This provides a guide for health facilities, health regulators, and health application developers on how to implement an integrated IIS in Indonesia.

Human papillomavirus (HPV) vaccination rates are lower than Tetanus-diphtheria-pertussis (Tdap) and Meningococcal conjugate (MenACWY) rates, although the Advisory Committee on Immunization Practices recommends all three vaccines be given routinely at age 11-12. Evidence is mounting that children who initiate HPV vaccination starting at age 9 are more likely to complete the series on time. Washington state implemented a provider reminder through its immunization information system (WAIIS) in January 2023 to increase HPV vaccine initiation at 9-years-old by updating the forecasted recommended age for HPV from age 11 to 9. The effectiveness of provider reminders when implemented via an immunization information system (IIS) is poorly understood. We evaluated the impact of this forecast update using a seasonally adjusted interrupted time series regression of weekly HPV initiations at 9-years-old before and after implementation. We also examined time series trends of vaccine administration between 2018 and 2023 for HPV initiation at age 9, as well as Tdap, MenACWY and HPV initiation at age 11. The WAIIS forecast update doubled the weekly rate of HPV initiation among 9-year-olds in Washington state, although the weekly count of initiation at 9 remains far lower than initiations at 11. Jurisdictions wanting to increase HPV vaccine initiation at earlier ages should consider updating their forecast algorithm and investing in complementary evidence-based strategies such as provider and parent education, and clinic-based quality improvement efforts. The reach of IIS forecaster updates may be enhanced by working with administrators of electronic medical record systems to ensure parity of provider prompts with IIS.

Immunization Information Systems (IIS) play an important information-sharing role at the point of care, and provide vital vaccination data for research studies and policy-makers. Previous validation studies comparing the accuracy of state registry data to health records have had mixed results.
We conducted a retrospective review of EHR vaccination data for 9-17 year-old patients from 10 Oregon primary care clinics who had at least one ambulatory care visit in the past 3 years from the date of validation data collection. Data on 100 age eligible youth were captured per clinic. We compared HPV and Tdap vaccinations captured in the EHR to the Oregon ALERT IIS. All clinics were located in rural areas with both family medicine (n = 7) and pediatric (n = 3) primary care clinics.
Overall agreement for HPV vaccination between EHR and ALERT IIS was 89.4 % (k = 0.83; p < 0.05). For Tdap vaccination overall agreement was 80.8 % (k = 0.60; p < 0.05). Pediatric clinics showed a higher overall vaccine agreement for both HPV at 93.3 % (k = 0.89; p < 0.05) and Tdap at 95.3 % (k = 0.90; p < 0.05). Among clinics that used bidirectional data exchange (only family medicine clinics), HPV agreement was higher at 91 % (k = 0.85) versus 88 % (k = 0.81; p < 0.05) and was lower for Tdap 75 % with bidirectional data exchange (k = 0.50) versus 86 % without bidirectional data exchange (k = 0.70; p < 0.05). When the EHR and ALERT IIS disagreed, ALERT ISS usually had additional vaccines.
ALERT IIS data provides more accurate data than EHRs can provide when measuring vaccine delivery among adolescents in rural Oregon.

Public health information systems have historically been siloed with limited interoperability. The State of Minnesota\'s disease surveillance system (Minnesota Electronic Disease Surveillance System: MEDSS, ∼12 million total reportable events) and immunization information system (Minnesota Immunization Information Connection: MIIC, ∼130 million total immunizations) lacked interoperability between them and data exchange was fully manual. An interoperability tool based on national standards (HL7 and SOAP/web services) for query and response was developed for electronic vaccination data exchange from MIIC into MEDSS by soliciting stakeholder requirements (n = 39) and mapping MIIC vaccine codes (n = 294) to corresponding MEDSS product codes (n = 48). The tool was implemented in March 2022 and incorporates MIIC data into a new vaccination form in MEDSS with mapping of 30 data elements including MIIC demographics, vaccination history, and vaccine forecast. The tool was evaluated using mixed methods (quantitative analysis of user time, clicks, queries; qualitative review with users). Comparison of key tasks demonstrated efficiencies including vaccination data access (before: 50 clicks, >2 min; after: 4 clicks, 8 s) which translated directly to staff effort (before: 5 h/week; after: ∼17 min/week). This case study demonstrates the contribution of improving public health systems interoperability, ultimately with the goal of enhanced data-driven decision-making and public health surveillance.

BACKGROUND: Immunization is critical to saving children from infections. To increase vaccination coverage, valid and real-time data are needed. Accordingly, it is essential to have a good report system that serves as defaulter tracking to prevent children\'s immunization failure. The Daerah Istimewa Yogyakarta (DIY) Health Office introduced an electronic immunization registry and successfully implemented it for more than five years. It is the only individual-based record system in Indonesia that has been sustainably operated for a long time. Yet, no systematic assessment of this system has been conducted to date. This study examines the Sistem Informasi Imunisasi Terpadu (SIMUNDU) introduction and implementation process with a view to extracting lessons that could inform scalability and sustainability across the country.
METHODS: This study used an explanatory sequential mixed-method design, which collected quantitative data from 142 participants and qualitative data from nine participants. The data entry clerk at a health facility was systematically selected to participate in the survey, while in the key informant interview, the informant was selected based on the survey result. A descriptive and thematic approach was adopted to analyze the quantitative and qualitative data. Results from across the two approaches were integrated for comparison and contrast.
RESULTS: Findings are presented according to three core themes that emerged from the data: system strengths, potential threats, weakness and opportunities for scaling-up. Strengths, i.e., factors contributing to the success of SIMUNDU, include management, system performance, people\'s behavior, and resources. Potential threats to sustaining the system include individual capacity, technical or system issues, and high workload. Opportunities - i.e., a promising factor that influences the SIMUNDU ability to operate sustainably - such as continuity, expectation, and the possibility of scaling up.
CONCLUSIONS: SIMUNDU is a promising innovation for Indonesia, beyond DIY. There is agreement about the potential for scaling up this IIS to other provinces. The experience of implementing this system in DIY over the past five years has shown that the benefits outweigh the challenges, and SIMUNDU has grown into a robust yet user-friendly system.

COVID-19 vaccination uptake has been suboptimal, even in high-risk populations. New approaches are needed to bring vaccination data to the groups leading outreach efforts. This article describes work to make state-level vaccination data more accessible by extending the Bulk Fast Healthcare Interoperability Resource (FHIR) standard to better support the repeated retrieval of vaccination data for coordinated outreach efforts. We also describe a corresponding low-foot-print software for population outreach that automates repeated checks of state-level immunization data and prioritizes outreach by social determinants of health. Together this software offers an integrated approach to addressing vaccination gaps. Several extensions to the Bulk FHIR protocol were needed to support bulk query of immunization records. These are described in detail. The results of a pilot study, using the outreach tool to target a population of 1500 patients are also described. The results confirmed the limitations of current patient-by-patient approach for querying state immunizations systems for population data and the feasibility of a Bulk FHIR approach.