Pediatric Vaccine Research Articles

1727. Household Vaccination Status and Attitudes towards Pediatric COVID-19 Vaccination: A survey at four New Jersey clinic-based pediatric practices

Abstract Background Although COVID-19 vaccination has been recommended for all children 6 months of age and older since August 2022, vaccine uptake among the pediatric population is low. Underlying caregiver attitudes towards pediatric COVID-19 vaccination have not been adequately classified or described. A better understanding of how caregiver attitudes influence household vaccination behavior can help tailor future vaccine interventions. Methods Unvaccinated children aged 18 months to 11 years underwent antibody testing and their caregivers were asked to complete an electronic survey at four clinic-based practices in Northern and Central NJ from September 2022 to April 2023. Information was collected on household exposures, vaccination status, COVID-19 infection, and caregiver beliefs about pediatric vaccination. Latent class analyses were conducted to group caregivers into four distinct profiles based on how safe, effective, useful and necessary they felt vaccination was. Results A total of 656 survey participants were grouped into a vaccine acceptance class based on their level of agreement on each attitudinal item, from low to high. Those in Class 1 had the most disagreement and lowest vaccine acceptance; those in Class 4 had the most agreement and highest vaccine acceptance. The majority of the sample fit into Class 2 (39%), indicating moderate disagreement and low COVID-19 vaccine acceptance. Caregivers in the lowest vaccine acceptance classes (1 & 2) were significantly less likely to plan to vaccinate their children compared to those in higher classes (3 & 4); (9.8% and 5.5% vs. 31.9% and 61%). Those in Class 2 were significantly less likely to have at least one adult household member fully vaccinated or boosted against COVID-19 than those in higher classes; and were significantly more likely to be from households where at least one adult was diagnosed with COVID in the past year than those in Class 3 (54.2% vs 37.7%). Conclusion Caregiver attitudes towards vaccination, and inclusion in vaccine acceptance classes, is closely associated with household vaccination status and COVID-19 infection history. Educational efforts and messaging should target the different aspects of caregiver profiles to address vaccine hesitancy and make future vaccine programming for children more successful. Disclosures Joseph V. Schwab, MD, MPH, Bristol-Myers Squibb: Stocks/Bonds|GE Healthcare: Stocks/Bonds|Johnson and Johnson: Stocks/Bonds

1740. Healthcare Providers’ Preferences for Pediatric Pneumococcal Vaccination Recommendations in the United States

Abstract Background A 20-valent pneumococcal conjugate vaccine (PCV20) was recently licensed for use in children by the United States (US) Food and Drug Administration. PCV20 includes 5 and 7 more serotypes than the 15- (PCV15) and 13-valent (PCV13) vaccines, respectively. This study assessed healthcare providers’ (HCPs) preferences for possible changes in pediatric pneumococcal vaccination recommendations, including transitioning from lower-valent vaccines to PCV20 among children partially vaccinated with PCV13/15, administering a supplemental dose of PCV20 among children < 5 years vaccinated with PCV13/15, and using PCV20 alone instead of in sequence with 23-valent pneumococcal polysaccharide vaccine (PPSV23) in children with underlying medical conditions. HCP preferences for the use of PCV15 or PCV20 for children aged ≤ 18 years were also elicited. Methods Pediatricians (N = 268), family medicine physicians/general practitioners (N = 184), physician assistants (N = 77), and nurse practitioners (N = 74) who prescribed, recommended, or administered a pneumococcal vaccine to a child ≤ 18 years in the past 3 months completed an online survey. HCPs responded to direct elicitation questions to assess preferences for each of the potential pneumococcal vaccination recommendations considered above. Practice characteristics, knowledge and awareness of current pediatric pneumococcal vaccination recommendations, and rationale for choices in the preference questions were also assessed. Results HCPs preferred recommendations that provided protection against more serotypes; 76% of HCPs in this study favored transitioning children who started vaccination with PCV13/15 to PCV20 (Figure 1A), and most (≥ 60%) favored a supplemental dose of PCV20 for all children < 5 years fully vaccinated with PCV13/15 (Figure 1B/1C). 93% of surveyed HCPs preferred PCV20 over PCV15 for children ≤ 18 years (Figure 1E). Among those who preferred PCV20, more than 80% based their decision mainly on serotype coverage.Figure 1.HCP Preferences for Potential Changes to Current Pediatric Pneumococcal Vaccine Recommendations Conclusion HCPs indicated preference for pediatric pneumococcal vaccination recommendations that provide greater serotype coverage. These results and other data on stakeholder preferences will help inform the updated pediatric pneumococcal vaccination recommendations. Disclosures Jeffrey T. Vietri, PhD, Pfizer Inc: Employment|Pfizer Inc: Stocks/Bonds Liping Huang, MD, MA, MS, Pfizer Inc.: Stocks/Bonds Vincenza Snow, MD, Pfizer Vaccines: employee|Pfizer Vaccines: Stocks/Bonds Brett Hauber, PhD, Pfizer: Brett Hauber is an employee of Pfizer. this study was funded by Pfizer, Inc.|Pfizer: Stocks/Bonds Adriano Arguedas, Medical director, Pfizer: Emplyee|Pfizer: Stocks/Bonds Alejandro D. Cane, MD, PhD, Pfizer: Stocks/Bonds Maria J Tort, PhD, Pfizer Inc: Stocks/Bonds Anna Pierce, BBA, Pfizer, Inc.: Grant/Research Support

546. COVID-19 Monoclonal Antibody Use at a Stand Alone Children’s Hospital

Abstract Background Texas Children’s Hospital (TCH) implemented an outpatient clinic for eligible patients to receive infusions when COVID monoclonal antibodies (mAbs) were approved for use in non-hospitalized, high-risk patients with mild to moderate COVID-19. There are limited data evaluating the use of outpatient COVID mAbs in pediatric patients. We describe the clinical characteristics and outcomes of the patients treated with COVID mAbs at TCH. Methods Patients that were referred to receive COVID mAbs from 12/1/2020 to 5/5/2022 were included. Information collected included demographics, comorbidities, refusal reason, adverse events, emergency center (EC) visits or admission within 14 days after final dose, and EC visit or admission within 14 days of referral if patients did not receive COVID mAbs. Chi-square was used to determine differences between the groups. Results There were 262 patients referred during the study period. The median age of all referred patients was 15.8 years (IQR 14-17.4 years). Majority of referrals were for treatment of COVID-19 infection rather than post-exposure prophylaxis (92.8% vs 7.2%). Of the 262 referrals, 134 patients received COVID mAbs (51.2%) while 128 patients were not treated. Majority of the patients received casirivimab-imdevimab (73.9%). The comorbidities of all patients are shown in Figure 1. The most common reasons for patients to not receive COVID mAbs were no drug available or not listed, and the full list of reasons are listed in Figure 2. The median time from reported symptom onset to infusion was 4 days (IQR 2-6 days). Of the 134 infused patients, 8 patients (6%) visited the EC within 14 days from infusion, and 6 (4.5%) were admitted while 4 patients (3.1%) that did not receive an antibody visited the EC resulting in 3 admissions (2.3%) (EC visits p=0.27; admissions p=0.34). There were 11 patients (8.2%) that experienced adverse events from their infusion, which led to 5 of the 8 EC visits. Comorbidities were similar across the infused and non-infused groups (p=0.16). Number of high-risk conditions represented by all referred, high-risk patients Number of patients for each reason for not receiving a COVID-19 antibody infusion Conclusion COVID mAb treatments were well tolerated among pediatric patients. Majority of patients in both groups did not require EC visit or hospitalization. More data are needed to determine the clinical efficacy of mAbs patients. Disclosures Flor M. Munoz, MD, MSc, CDC respiratory virus surveillance: Grant/Research Support|Gilead: Grant/Research Support|Moderna, sanofi, aztra zeneca, Merck, GSK: Advisor/Consultant|NIH: DSMB|NIH COVID-19 vaccines in pregnancy: Grant/Research Support|Pfizer Pediatric COVID-19 vaccines: Grant/Research Support|Pfizer, Dynavax, Monderna, Meissa, NIH: DSMB Lisa Forbes Satter, MD, ADMA: Advisor/Consultant|CsL Behring: Advisor/Consultant|Grifols: Advisor/Consultant|incyte: Advisor/Consultant|Pharming: Advisor/Consultant|Takeda: Advisor/Consultant

660. Pediatric Rotavirus Hospitalization Rates in the Military Health System Before and During the COVID-19 Pandemic

Abstract Background Rotavirus, a vaccine preventable disease, causes significant morbidity and mortality in children < 5 years of age. Globally, the COVID-19 pandemic reduced the rates of pediatric vaccinations, and the Military Health System (MHS) was no different (Figure 1). This gap in immunizations left many children vulnerable to preventable illnesses, including rotavirus. We hypothesized that the reduction in rotavirus vaccine administration during the pandemic would lead to an increase in rotavirus related hospitalizations within the MHS. Methods A repeated monthly cross-sectional study was performed using inpatient data from the MHS to observe differences in rotavirus rates and risk factors before and during the COVID-19 pandemic. Data from March 2018 to February 2020 was considered pre-pandemic, while the following two years (until February 2022), were divided into COVID Year 1 and Year 2. Children included in the study were between 0-59 months of age and those with rotavirus were identified using ICD-10 codes. Poisson regression calculated rate ratios of rotavirus, adjusting for several demographic variables and time period at diagnosis. Monthly counts and rates of rotavirus were also documented. Results Across the cohort of 1.14 million MHS beneficiaries, there were 3,503 unique cases of rotavirus infections in hospitalized children < 5 years old (Table 1). During both Years 1 and 2 of COVID-19, there was a significant decrease in rotavirus related hospitalizations compared to the pre-pandemic period (Figure 2). Younger age was associated with increased risk. Patient sex, parent military rank, and region were not statistically significant (Table 2). Conclusion Despite the reduction in routine immunization administration to children in the MHS after the COVID-19 pandemic started, there was not an increase in rotavirus related hospitalizations. In the two years following the start of the pandemic, there was a statistically significant decrease in hospitalizations related to rotavirus in our cohort. Social distancing to include daycare closures, increased hygiene measures, and catch-up immunizations may explain this finding. Continued research into this topic will help determine if rotavirus related hospitalizations return to pre-pandemic levels. Disclosures All Authors: No reported disclosures

Understanding paediatric COVID-19 vaccination during the pandemic: a prospective cohort and a population-based registry study

Understanding paediatric COVID-19 vaccination during the pandemic: a prospective cohort and a population-based registry study

Sociodemographic factors and attitudes associated with Australian parental acceptance of paediatric COVID-19 vaccination

IntroductionThe COVID-19 vaccine coverage among children in countries where COVID-19 vaccines are recommended has been suboptimal. Conflicting information in the media leads to parental anxiety and confusion around COVID-19 vaccination in children. The scepticism expressed by certain experts regarding the importance of COVID-19 vaccines in children has also had a negative impact on parental attitudes towards COVID-19 vaccination. This study aimed to understand parental concerns and preferences for paediatric COVID-19 vaccination, and identify potential vaccination promotion (“nudge”) interventions to optimise paediatric COVID-19 vaccine uptake. MethodsMixed methods including Focus Group Discussions and a Discrete Choice Experiment survey were used. The Discrete Choice Experiment survey design was based on a literature review and the findings of Focus Group Discussions. The study was conducted on a nationally representative sample of parents in Australia. ResultsIn total, 1039 parents participated in the study. Parents showed strong preferences for a COVID-19 vaccine with lower risk of serious side effects and longer protection duration, followed by higher vaccine effectiveness and delivery via oral tablets. Promotion strategies were similarly preferred by parents. Latent class logit analysis identified three groups, interpretable as COVID-19 vaccine “accepters (35.3%)”, “deliberators (31.7%)”, and “rejecters (33.1%)”. The “deliberators” composed of more parents, residing in metropolitan areas, having concerns about vaccine effectiveness, and believing that disease risks outweigh vaccine benefits than the “accepters”. The “rejecters” were more likely to not be vaccinated themselves, and generally have less trust in vaccines than the “accepters”. The “deliberators” and “rejecters” were less likely to be parents aged ≥25 years and complete final year of high school than the “accepters”. ConclusionsParents’ sociodemographic factors and vaccine perceptions were associated with different levels of acceptance toward paediatric COVID-19 vaccination, which may help to better understand how to “nudge” vaccine hesitancy.

Pediatric influenza vaccination in the perioperative setting: A quality improvement project.

Unmet need for seasonal influenza vaccination administration to pediatric patients exists at national and local levels. Vaccination during the perioperative period remains controversial, though opportunity exists to meet vaccination need through perioperative programs. The initial SMART Aim of this quality improvement initiative was to establish and increase seasonal influenza vaccination rate in eligible patients during in person preoperative clinic visits in a pediatric perioperative surgical home (PSH) to 10%. Informed by each prior season's experience, we increased our SMART Aim target for vaccinations in seasons two and three to 15 and 18%, respectively. Following the Model for Improvement methodology, the PSH team developed and implemented a perioperative pediatric influenza vaccination program. Across three influenza seasons, key interventions included updates to organizational perioperative vaccination policy, obtaining material influenza vaccination supplies, development of EHR tools, PSH staff education, and communication with patient-families. Rate of eligible patients receiving influenza vaccination at their PSH clinic appointment was tracked over time. Influenza vaccination rates were reported monthly during Season 1, then weekly during seasons two and three. The balancing measure was same day surgery case cancellations related to influenza vaccination given at PSH clinic appointment. Statistical analysis methods utilized include Shewart's control chart and statistical process control (SPC) standards. Special cause variation was determined by eight or more consecutive data points above or below the centerline. The influenza vaccination rates in each of the three influenza seasons exceeded vaccination rate goals of 10, 15, and 18%, respectively. A total of 695 vaccines have been administered since program inception. No same day surgical case cancellations were observed as balancing measure. Over three consecutive influenza vaccination seasons, we safely established and met vaccination rate goals of 10, 15, and 18% to eligible patients during preoperative clinic visits within a pediatric PSH system. Through iterative PDSA cycles, we continue to identify opportunities for future improvement. This suggests that the perioperative period presents opportunity for seasonal influenza vaccination with potential program expansion to include routine vaccines of childhood.

“Direct and indirect impacts of the COVID-19 pandemic on operational conduct of pediatric vaccine clinical trials”

ABSTRACT The coronavirus 2019 (COVID-19) pandemic, as well as the resulting public health measures, impacted many aspects of society. The conduct of important pediatric vaccine trials was among these. Analyzing data from six ongoing non-COVID-19 pediatric vaccine trials we aimed to assess the operational impact of the COVID-19 pandemic using descriptive analyses. We identified multiple operational disruptions in trial conduct. Additionally, we identified higher percentages of missed routine vaccinations than investigational vaccines throughout the observation period. Overall, the impact of the COVID-19 pandemic was most apparent early in the pandemic period while adaptations to the pandemic were developed; however, some disruptions persisted throughout the observation period. Pediatric vaccine clinical trials are critical to developing new and/or improved vaccines for the pediatric population. Continued evaluation of the impacts of COVID-19 on pediatric vaccine clinical trials is warranted.

Healthcare provider perspectives on COVID-19 vaccination for children in India

BackgroundThe rapid development and deployment of effective COVID-19 vaccines have been critical to halt the spread of the pandemic. India started vaccinating children in early 2022, however, vaccine uptake has...

Champions for School Health-An NASN Initiative to Increase Vaccine Confidence, Equity, and Uptake in COVID-19 and School-Required Vaccinations: Part 2.

NASN, with generous funding from Kaiser Permanente (KP) and partnered with the Institute for Educational Leadership, developed and implemented the Champions for School Health (CSH) grant initiative. The CSH initiative awarded 54 Implementation Grants in two funding cycles in 2022, funding school districts and community-based organizations (CBOs) to increase access to the pediatric COVID-19 vaccine as well as school-required immunizations and to increase vaccine confidence among underserved populations in KP's footprint: California, Colorado, Georgia, Hawaii, Maryland, Oregon, Virginia, Washington, and the District of Columbia. These grantees administered a total of 17,630 COVID-19 vaccines to individuals ages 5 or older and 34,025 routine immunizations, of which 8,233 school-required vaccinations went to children of ages 5-11 years. Over 851,000 people were reached by vaccine education events in all nine KP markets. A notable takeaway from the project's results was the new partnerships created and the continuation of existing partnerships by the grantees. NASN's implementation of the CSH initiative and results provides a model and a source of critical data on how school health services and community-based organizations can partner to provide hyper-local responses to community/public health crises. This Part 2 article provides an overview of the key results of the project.

The protective effects of pediatric vaccination on multisystem inflammatory syndrome in children stratified by vaccine status, types and virus variants

BackgroundFew studies highlight the stratification of COVID-19 vaccine effectiveness on MIS-C according to vaccine status, types and SARS-COV-2 variants. MethodsA web-based analysis was conducted through searches of PubMed, Web of Science and Medline databases from January 1, 2020, to May 16, 2023. The search terms used were (multisystem inflammatory syndrome in children OR MIS-C OR PIMS OR PIMS-TS) AND (COVID-19 OR SARS-CoV-2) AND (vaccine OR vaccination) AND (children OR adolescents OR pediatric). Results6701 children from 13 studies met the MIS-C definition. 92.1 % (1332/1446) of MIS-C cases were unvaccinated, whereas partial vaccination and full vaccination were 3.7 % (54/1446) and 4.2 % (60/1446)respectively. In the two studies encompassing 41 vaccinated MIS-C cases, 34 (82.9 %) received BNT162b2, 2 (4.9 %) received mRNA-1273, 4 (9.8 %) received Sinovac vaccine, and only one received a heterologous primary-boost regimen. Among 838 vaccinated MIS-C cases with different SARS-COV-2 variants, 23（2.8 %） were infected by the Wild-type, 80（9.5 %） by the Alpha variant, 521（62.2 %） by the Delta variant, and 214（25.5 %） by the Omicron variant. A significant difference was observed in vaccination rates among MIS-C cases across different variant pandemics (χ2 = 37.79, P < 0.001). The highest vaccination rate (26.3 %) occurred in the Alpha predominant period, thereafter dropped to 5.0 % in the Delta predominant period, and then increased to 12.6 % in the Omicron predominant period. ConclusionsHeterologous vaccination might provide a slightly more protective effect than homologous manner for MIS-C. As the virus mutates over time, its pathogenicity to MIS-C degrades among vaccinated individuals.

COVID-19 Vaccine Hesitancy Among Parents: A Qualitative Study.

Addressing parental/caregivers' coronavirus disease 2019 (COVID-19) vaccine hesitancy is critical to improving vaccine uptake in children. Common concerns have been previously reported through online surveys, but qualitative data from KII and focus groups may add much-needed context. Our objective was to examine factors impacting pediatric COVID-19 vaccine decision-making in Black, Spanish-speaking, and rural white parents/caregivers to inform the content design of a mobile application to improve pediatric COVID-19 vaccine uptake. Parents/caregivers of children aged 2 to 17 years from groups disproportionately affected by COVID-19-related vaccine hesitancy (rural-dwelling persons of any race/ethnicity, urban Black persons, and Spanish-speaking persons) were included on the basis of their self-reported vaccine hesitancy and stratified by race/ethnicity. Those expressing vaccine acceptance or refusal participated in KII, and those expressing hesitancy in focus groups. Deidentified transcripts underwent discourse analysis and thematic analysis, both individually and as a collection. Themes were revised until coders reached consensus. Overall, 36 participants completed the study: 4 vaccine acceptors and 4 refusers via KIIs, and the remaining 28 participated in focus groups. Participants from all focus groups expressed that they would listen to their doctor for information about COVID-19 vaccines. Infertility was a common concern, along with general concerns about vaccines. Vaccine decision-making was informed by the amount of information available to parents/caregivers, including scientific research; possible positive and negative long-term effects; and potential impacts of vaccination on preexisting medical conditions. Parents/caregivers report numerous addressable vaccine concerns. Our results will inform specific, targeted interventions for improving COVID-19 vaccine confidence.

Emergency department presentations for chest complaints after mRNA COVID-19 vaccinations in children and adolescents.

To investigate characteristics and management of children presenting with chest complaints to a tertiary paediatric ED post-mRNA COVID-19 vaccine. This was a retrospective medical record review with data linkage to the Australian Immunisation Register. The study setting was the Royal Children's Hospital, Melbourne, Australia. Children <18 years who had a troponin blood test performed in hospital within 14 days of receiving mRNA COVID-19 vaccination were included. Elevated troponin and myocarditis or pericarditis as per Brighton criteria was the primary outcome. Vaccination status, length of stay, investigations and clinical management were secondary outcomes. Six hundred and ten patients had a troponin test in 13 months. After exclusion of trauma-related tests (n = 31), known cardiac patients (n = 75) and others (n = 145), 359 troponins were obtained due to chest complaints and related symptoms, with 283 troponins assessed to be mRNA vaccination-related. There was a temporal peak in presentations with a 30-fold monthly increase in troponin post-commencement of mRNA COVID-19 vaccines. In those with chest complaints following mRNA vaccination, mean age was 14 years and 50.4% were female. Fourteen out of 283 (5%) vaccine-related troponins were abnormal with 14 patients assessed to have vaccine-associated myocarditis. No patients had pericarditis. There was a large number of possible mRNA COVID-19 vaccine-related chest complaints presenting to the ED. Few patients had abnormal troponins or myocarditis.

Emergency departments: An underutilized resource to address pediatric influenza vaccine coverage

BackgroundEmergency department (ED) based influenza vaccine (IV) programs have been successful in adults; however, little is known about pediatric ED IV programs in terms of prevalence, feasibility, or successful implementation. AimsTo describe the reach and effectiveness of IV practices in pediatric EDs, and identify IV facilitators and barriers. MethodsWe assessed, via cross-sectional survey of pediatric ED physicians, number of EDs offering IV to children, vaccines administered annually, and perceived facilitators/barriers to vaccination. The proportion of EDs offering IV is reported. Chi-square tests compared facilitators and barriers among high performers (≥50 IV/year), low performers (<50 IV/yr), and non-vaccinators. We calculated an area of missed effect for the number of children who could be vaccinated if non-vaccinating EDs offered IV. ResultsAmong 492 physicians from 166 EDs, 142 responded (representing 61 (37.3 %) EDs). Most EDs were in large, urban, academic, freestanding children’s hospitals (Table 1). Only twenty-six EDs (44.3 %) offer ≥ 1 IV/yr. Seventeen (65.4 %) were low performers, five (19.2 %) high performers, and four (15.4 %) were model programs. High/model performers used establish workflows more commonly than lower performers (78 % vs. 33 %), although this was not statistically significant (p = 0.077). Common facilitators included: strong provider and administration buy-in, electronic health record facilitation, storage/accessibility, and having a leadership team/champion (Fig. 1). Non-vaccinators commonly perceived lack of these factors as barriers. Many (24/61, 39.3 %) EDs expressed interested in establishing or growing IV programs. Up to 18,250 unvaccinated children could receive IV annually if non-vaccinating EDs offered IV during influenza season. ConclusionsOver half of EDs participating in the Pediatric Emergency Medicine Collaborative Research Committee do not currently offer pediatric IV. Addressing identified barriers/facilitators to develop IV programs in EDs has potential to improve vaccination rates, especially among minority and underserved children.

Public economic gains from tax-financed investments in childhood immunization in the United States.

The emergence of COVID-19 has displayed the importance of immunization and the need for continued public investment in vaccination programs. Globally, national vaccination programs rely heavily on tax-financed expenditure, requiring upfront investments and ongoing financial commitments. To evaluate annual public investments, we conducted a fiscal analysis that quantifies the public economic consequences to government in the United States attributable to childhood vaccination. To estimate the change in net government revenue, we developed a decision-analytic model that quantifies lifetime tax revenues and transfers based on changes in morbidity and mortality arising from vaccination of the 2017 U.S. birth cohort. Reductions in deaths and comorbid conditions attributed to pediatric vaccines were used to derive gross lifetime earnings gains, tax revenue gains attributed to averted morbidity and mortality avoided, disability transfer cost savings, and averted special education costs associated with each vaccine. Our analysis indicates a fiscal dividend of $41.7 billion from vaccinating this cohort. The bulk of this gain for government reflects avoiding the loss of $30.6 billion in present-value tax revenues. All pediatric vaccines raise tax revenues by reducing vaccine-preventable morbidity and mortality in amounts ranging from $7.3 million (hepatitis A) to $20.3 billion (diphtheria) over the life course. Based on public investments in pediatric vaccines, a benefit-cost ratio of 17.8 was calculated for each dollar invested in childhood immunization. The public economic yield attributed to childhood vaccination in the U.S. is significant from a government perspective, providing fiscal justification for ongoing investment.

High Caregiver Adverse Childhood Experiences Are Associated With Pediatric Influenza and COVID-19 Vaccination Uptake.

Factors surrounding vaccine uptake are complex. Although anxiety, which could influence vaccination decisions, has been associated with adverse childhood experiences (ACEs), little is known about links between caregiver ACEs and pediatric vaccine uptake. We evaluated associations between caregivers' ACEs and decisions to vaccinate their children with influenza and coronavirus disease (COVID-19) vaccines. A cross-sectional study of caregivers of patients ≥6 months at one pediatric primary care center (PPCC) was performed. Caregivers completed a 19-question survey examining caregiver ACEs, influenza vaccine acceptance and beliefs, and intention to vaccinate their child with the COVID-19 vaccine. Demographic characteristics, social risks (eg, housing and food insecurity), and vaccination data for children present with each caregiver were extracted from the electronic health record (EHR). Statistical analyses included χ2 tests for categorical variables and t-tests for continuous variables. A total of 240 caregivers participated, representing 283 children (mean age of 5.9 years, 47% male). Twenty-four percent (n = 58) had high ACEs (≥4). Of those with high ACEs, 55% accepted pediatric influenza vaccination compared with 38% with low ACEs (P = .02). Those with high ACEs had more positive attitudes toward influenza vaccine safety and efficacy (P ≤ .02). Those with high, compared with low, ACEs were also more likely to accept COVID-19 vaccination (38% vs 24%; P = .04). Pediatric influenza vaccination rates and intention to vaccinate children against COVID-19 differed between caregivers with high and low ACEs: those with more ACEs were more likely to vaccinate. Further studies assessing the role of caregiver ACEs on vaccine decision-making are warranted.

Designing drone delivery networks for vaccine supply chain: a case study of Niger

This research aims to evaluate the use of drones to deliver pediatric vaccines in remote areas of low-income and low-middle-income countries. Delivering vaccines in these regions is challenging because of the inadequate road networks and long transportation distances that make it difficult to maintain the cold chain’s integrity during delivery. We propose a mixed-integer linear program to determine the location of drone hubs to facilitate vaccine delivery. The model considers the operational attributes of drones, vaccine wastage in the supply chain, cold storage, and transportation capacities. We develop a case study using data from Niger to determine the impact of drone deliveries in improving vaccine availability. Based on our numerical analysis, regional centers should be considered potential locations for drone hubs. We demonstrate that outreach sessions supported by drone deliveries of vaccines can improve vaccine availability. These improvements depend on the available budget to build drone hubs and purchase drones, available cold storage capacity, and the population density in the study region.

Parental anxiety and pediatric vaccine refusal in a US national sample of parents

ObjectivesUnderstanding vaccine hesitancy among parents is of emerging interest and of rising importance for promoting vaccine uptake to prevent pediatric illness. Here, we examine associations between pediatric vaccine refusal and parental symptoms of anxiety. MethodsOur cross-sectional survey assessed pediatric vaccine refusal in 1699 parents in a US national sample. Participants completed a sociodemographic questionnaire, the Vaccine Hesitancy Scale, and symptoms of anxiety (GAD-7). ResultsThe prevalence of pediatric vaccine refusal was 15.5 %. Parent symptoms of anxiety were related to vaccine refusal (OR = 1.07 [1.03, 1.10]). Mild (1.88 [1.39, 2.54], p <.001) and clinically significant (2.14 [1.39, 3.31], p <.001) symptoms of anxiety were also related to pediatric vaccine refusal.Parental anxiety was also associated with perceived risks of vaccines and reduced confidence. ConclusionsFindings highlight the need to consider parental anxiety in the development of public health interventions that address substandard pediatric vaccine uptake.

Pediatric COVID-19 Vaccination in the Inpatient Setting.

The inpatient setting is often underutilized as a venue for providing pediatric vaccines. During the 2019 novel coronavirus (COVID-19) pandemic, our hospital began a vaccination program to provide access to COVID-19 vaccines for eligible pediatric inpatients. Our objective was to describe the establishment and assess the impact of a COVID-19 vaccination program for pediatric inpatients. All admitted patients were screened for eligibility and interest in inpatient COVID-19 vaccination upon admission from April 27, 2021 until February 12, 2022. For those eligible for vaccination, their interest was recorded and shared with the clinical team. The clinical team completed education and/or vaccination depending on individual case. Interest in inpatient vaccination and ultimate receipt of a vaccine was recorded and analyzed. During the study period, 1615 patients were eligible for inpatient vaccination and 1601 had their interest recorded on hospital admission. Twenty-one percent of these patients were interested, 50% declined, and 28% were unsure. Twenty-nine percent of those initially interested were given vaccine by the clinical team before discharge. Six percent of patients who were unsure and 2% of those who declined vaccine on admission were vaccinated before discharge. The inpatient setting can be an important venue to allow for education and discussion regarding pediatric COVID-19 vaccine and to improve access to vaccination for a traditionally under-vaccinated population. Challenges remain with consistent vaccine administration even for interested pediatric inpatients.

Transplacental transfer efficiency of maternal antibodies against influenza A(H1N1)pdm09 virus and dynamics of naturally acquired antibodies in Chinese children: a longitudinal, paired mother–neonate cohort study

The 2009 pandemic H1N1 influenza A virus (A(H1N1)pdm09 virus) evolves rapidly and has continued to cause severe infections in children since its emergence in 2009. We aimed to characterise the kinetics of maternally and naturally acquired antibodies against historical A(H1N1)pdm09 strains and to assess the extent to which the response to heterologous strains following infection or vaccination affects observed A(H1N1)pdm09 strain-specific antibody titres in a Chinese paediatric population. In this retrospective study, we used residual serum samples from 528 mother-neonate pairs from a non-interventional, longitudinal cohort study in southern China conducted from Sept 20, 2013, to Aug 24, 2018, from six local hospitals in Anhua County, Hunan Province, China. Mother-neonate pairs were eligible for inclusion if the neonates were born after Sept 20, 2013, and their mothers had resided in the study sites for at least 3 months. We tested samples with a haemagglutination inhibition (HAI) assay to measure antibody levels against three historical A(H1N1)pdm09 strains that were antigenically similar to the strains that circulated during the 2009 pandemic (A/Hunan-Kaifu/SWL4204/2009 [SWL4204/09 strain], A/Hunan-Daxiang/SWL1277/2016 [SWL1277/16 strain], and A/Hunan-Yanfeng/SWL185/2018 [SWL185/18 strain]). We also determined the seroprevalence, geometric mean titres (GMTs), transfer ratio of maternal antibodies, and the dynamics of maternally and naturally acquired antibodies in children, from birth to 3 years of age. 1066 mother-neonate pairs were enrolled in the original cohort between Sept 20, 2013, and Oct 14, 2015. Of these, 528 pairs (523 mothers, 528 neonates) were selected for the present study. The median age of the mothers was 25 years (IQR 23 to 29). 291 (55%) of 528 children were boys and 237 (45%) were girls, and most children (452 [86%]) were breastfed before the age of 6 months. The GMTs and the seroprevalence for the SWL4204/09 strain were higher than those for the SWL1277/16 and SWL185/18 strains among mothers (GMTs: 10·4 [95% CI 9·8 to 11·1] vs 9·3 [8·7 to 9·8] vs 8·0 [7·5 to 8·4], p<0·0001; seroprevalence: 11·1% [95% CI 8·5 to 14·1] vs 6·9% [4·9 to 9·4] vs 4·6% [3·0 to 6·8], p=0·0003) and among neonates (GMTs: 10·7 [10·0 to 11·5] vs 9·4 [8·8 to 10·0] vs 8·1 [7·6 to 8·6], p<0·0001; seroprevalence: 13·4% [10·7 to 16·7] vs 8·7% [6·5 to 11·5] vs 6·1% [4·2 to 8·5], p=0·0002). Regardless of the A(H1N1)pdm09-specific strain, maternal antibodies could be transferred efficiently via the placenta (mean transfer ratios: 1·10 for SWL4204/09 vs 1·09 for SWL1277/16 vs 1·06 for SWL185/18; p=0·93). The A(H1N1)pdm09 strain-specific antibodies waned below the protective threshold of 1:40 within 2 months after birth. After maternal antibody waning, there were periodic increases and decreases in HAI antibody titres against three A(H1N1)pdm09 strains, and such increases were all significantly associated with a higher immune response to heterologous strains. Vaccination against the SWL4204/09 strain was associated with a poor response to the SWL185/18 strain (β-0·20, 95% CI -0·28 to -0·13; p<0·0001). Our findings suggest low pre-existing immunity against influenza A(H1N1)pdm09 virus among unvaccinated Chinese adult female and paediatric populations. This evidence, together with the rapid decay of maternal antibodies and the observed cross-reactivity among different A(H1N1)pdm09 strains, highlights the importance of accelerating maternal and paediatric influenza vaccination in China. The Key Program of the National Natural Science Foundation of China. For the Chinese translation of the abstract see Supplementary Materials section.